FINAL DRAFT Chapter 15 IPCC WGII Sixth Assessment Report
1
2 Chapter 15: Small Islands
3
4 Coordinating Lead Authors: Michelle Mycoo (Trinidad and Tobago), Morgan Wairiu (Solomon Islands)
5
6 Lead Authors: Donovan Campbell (Jamaica), Virginie Duvat (France), Yimnang Golbuu (Palau),
7 Shobha Maharaj (Germany/Trinidad and Tobago), Johanna Nalau (Australia/Finland), Patrick Nunn
8 (Australia), John Pinnegar (United Kingdom), Olivia Warrick (New Zealand)
9
10 Contributing Authors: Giulia Anderson (USA/New Caledonia), Faye Abigail Cruz (Philippines), Eleanor
11 Devenish-Nelson (United Kingdom), Kris Ebi (USA), Johanna Loehr (Germany), Roché Mahon (Trinidad
12 and Tobago), Rebecca McNaught (Australia), Meg Parsons (New Zealand), Jeff Price (United Kingdom),
13 Stacy-Ann Robinson (Jamaica), Adelle Thomas (Bahamas)
14
15 Review Editors: John Agard (Trinidad and Tobago), Mahmood Riyaz (Maldives)
16
17 Chapter Scientist: Giulia Anderson (USA/New Caledonia)
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19 Date of Final Draft: 1 October 2021
20
21 Notes: TSU Compiled Version
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23
24
25 Table of Contents
26
27 Executive Summary..........................................................................................................................................3
28 15.1 Introduction ..............................................................................................................................................7
29 15.2 Points of Departure from AR5 ................................................................................................................8
30 15.2.1 Points of Departure on Exposure, Vulnerability, Impacts and Risks .............................................9
31 15.2.2 Points of Departure on Adaptation.................................................................................................9
32 15.3 Observed Impacts and Projected Risks of Climate Change...............................................................10
33 15.3.1 Synthesis of Observed and Projected Changes in the Physical Basis ..........................................10
34 15.3.2 Trends in Exposure and Vulnerability ..........................................................................................12
35 15.3.3 Observed Impacts and Projected Risks on Natural Systems ........................................................13
36 15.3.4 Observed Impacts and Projected Risks on Human Systems ........................................................23
37 Box 15.1: Key Examples of Cumulative Impacts from Compound Events: Maldives Islands and
38 Caribbean Region...................................................................................................................................32
39 Box 15.2: Loss and Damage and Small Islands ...........................................................................................34
40 15.4 Detection and Attribution of Observed Impacts of Climate Change on Small Islands ...................36
41 15.5 Assessment of Adaptation Options and Their Implementation .........................................................37
42 15.5.1 Hard Protection ............................................................................................................................37
43 15.5.2 Accommodation and Advance as Strategies .................................................................................38
44 15.5.3 Migration ......................................................................................................................................39
45 15.5.4 Ecosystem-based Measures ..........................................................................................................39
46 15.5.5 Community-based Adaptation.......................................................................................................41
47 15.5.6 Livelihood Responses....................................................................................................................42
48 15.5.7 Disaster Risk Management, Early Warning Systems and Climate Services.................................43
49 15.6 Enablers, Limits and Barriers to Adaptation ......................................................................................45
50 15.6.1 Governance ...................................................................................................................................45
51 15.6.2 Health-Related Adaptation Strategies ..........................................................................................46
52 15.6.3 Adaptation Finance and Risk Transfer Mechanisms ....................................................................47
53 15.6.4 Education and Awareness-Raising ...............................................................................................49
54 15.6.5 Culture ..........................................................................................................................................49
55 15.7 Climate Resilient Development Pathways and Future Solutions in Small Islands ..........................51
56 15.8 Research Gaps ........................................................................................................................................52
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1 FAQ 15.1: How is climate change affecting nature and human life on small islands, and will further
2 climate change result in some small islands becoming uninhabitable for humans in the near
3 future? .....................................................................................................................................................53
4 FAQ 15.2: How have some small-island communities already adapted to climate change? ...................54
5 FAQ 15.3: How will climate related changes affect the contributions of agriculture and fisheries to
6 food security in small islands?...............................................................................................................56
7 Large Tables....................................................................................................................................................58
8 References........................................................................................................................................................78
9
10
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1 Executive Summary
2
3 Observed Impacts
4
5 A sense of urgency is prevalent among small islands in the combating of climate change and in
6 adherence to the Paris Agreement to limit global warming to 1.5 °C above pre-industrial levels. Small
7 islands are increasingly affected by increases in temperature, the growing impacts of tropical cyclones (TCs)
8 , storm surges, droughts, changing precipitation patterns, sea-level rise (SLR), coral bleaching, and invasive
9 species, all of which are already detectable across both natural and human systems (very high confidence1)
10 {15.3.3.1, 15.3.3.2, 15.3.3.3, 15.3.4.1, 15.3.4.2, 15.3.4.3, 15.3.4.4, 15.3.4.5, 15.3.4.7}.
11
12 The observed impacts of climate change differ between urban and rural contexts, island types, and
13 tropical and non-tropical islands (high confidence). Coastal cities and rural communities on small islands
14 have been already impacted by sea-level rise, heavy precipitation events, tropical cyclones and storm surges.
15 Climate change is also affecting settlements and infrastructure, health and wellbeing, water and food
16 security, and economies and culture, especially through compound events (high confidence). As of 2017, an
17 estimated 22 million people in the Caribbean live below 6 metres elevation and 50% of the Pacific's
18 population lives within 10 km of the coast along with 50% of their infrastructure concentrated within 500
19 metres of the coast {15.3.4.1, 15.3.4.2, 15.3.4.3, 15.3.4.4, 15.3.4.5, 15.3.4.7}.
20
21 Tropical cyclones are severely impacting small islands (high confidence). The TC intensity and
22 intensification rates at a global scale have increased in the past 40 years with intensity trends generally
23 remaining positive. Intense TCs including categories 4 and 5 TCs have threatened human life and destroyed
24 buildings and infrastructural assets in small islands in the Caribbean and the Pacific. Among 29 Caribbean
25 islands, 22 were affected by at least one category 4 or 5 TC in 2017. TC Maria in 2017 destroyed nearly all
26 of Dominica's infrastructure and losses amounted to over 225% of the annual GDP. Destruction from TC
27 Winston in 2016 exceeded 20% of Fiji's current GDP. TC Pam devastated Vanuatu in 2015 and caused
28 losses and damages to the agricultural sector valued at USD 56.5 million (64.1% of GDP). Coast-focused
29 tourism is already extremely impacted by more intense TCs. {WGI 11.7.1, 12.4.7 15.2.1, 15.3.3.1, 15.3.3.3,
30 15.3.4.1, 15.3.4.2, 15,3.4.4, 15.3.4.5}.
31
32 Scientific evidence has confirmed that globally and in small islands tropical corals are presently at
33 high risk (high confidence). Severe coral bleaching, together with declines in coral abundance have been
34 observed in many small islands, especially those in the Pacific and Indian Oceans (high confidence). In the
35 Pacific, median return time between two severe bleaching events has diminished steadily since 1980. The
36 return time is now 6 years and often associated with the warm phase of ENSO events (high confidence). In
37 Mid-2016, a new ENSO event occurred which reduced living coral cover by 75% in the Maldives
38 {15.3.3.1.3, 15.3.4.8}.
39
40 Freshwater systems on small islands are exposed to dynamic climate impacts and are among the most
41 threatened on the planet. An 11-36% reduction is estimated in the volume of fresh groundwater lens of the
42 small atoll islands (area < 0.6 km²) of the Maldives due to SLR. The El Niño related 2015-16 drought in
43 Vanuatu led to reliance on small amounts of contaminated water left at the bottom of household tanks. A
44 Caribbean high-resolution drought atlas spanning 19502016 indicates that the region-wide 20132016
45 drought was the most severe event during the multi-decadal period. In Puerto Rico, the island experienced 80
46 consecutive weeks of moderate drought, 48 weeks of severe drought and 33 weeks of extreme drought
47 conditions between 2014 and 2016. Increasing trends in drought are apparent in the Caribbean although
48 trends in the western Pacific are not statistically significant {15.3.3.2, 15.3.4.3}.
49
50 Small islands host significant levels of global terrestrial species diversity and endemism. Due to the large
51 range of insular-related vulnerabilities, almost 50% of terrestrial species presently considered at risk of
52 global extinction also occur on islands (high confidence). Despite encompassing approximately two percent
1
In this Report, the following summary terms are used to describe the available evidence: limited, medium, or robust;
and for the degree of agreement: low, medium, or high. A level of confidence is expressed using five qualifiers: very
low, low, medium, high, and very high, and typeset in italics, e.g., medium confidence. For a given evidence and
agreement statement, different confidence levels can be assigned, but increasing levels of evidence and degrees of
agreement are correlated with increasing confidence.
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1 of the Earth's terrestrial surface, oceanic and other high-endemicity islands are estimated to harbour substantial
2 proportions of existing species including ~ 25% extant global flora, ~ 12% birds and ~10% mammals
3 {15.3.3.3}.
4
5 Projected Impacts
6
7 Projected climate and ocean-related changes will significantly affect marine and terrestrial ecosystems
8 and ecosystem services, which will in turn have cascading impacts across both natural and human
9 systems (high confidence). Changes in wave climate superimposed on SLR will significantly increase
10 coastal flooding (high confidence) and low-coastal and reef island erosion (limited evidence, medium
11 agreement). The frequency, extent, duration, and consequences of coastal flooding will significantly increase
12 from 2050 (high confidence), unless coastal and marine ecosystems are able to naturally adapt to SLR
13 through vertical growth (low confidence). These changes are a major concern for small islands given that a
14 high percentage of their population, infrastructure and economic assets are located in the low elevation
15 coastal zone of below 10 metres elevation {15.3.3.1.1, 15.3.3.1.2, 15.3.3.1.3, 15.3.3.1.4}.
16
17 Projected changes in the wave climate superimposed on SLR will rapidly increase flooding in small
18 islands, despite highly contrasting exposure profiles between ocean sub-regions (high confidence). A 5-
19 10 cm additional SLR (expected for ~20302050) will double flooding frequency in much of the Indian
20 Ocean and Tropical Pacific, while TCs will remain the main driver of (rarer) flooding in the Caribbean Sea
21 and Southern Tropical Pacific. Some Pacific atoll islands will likely2 undergo annual wave-driven flooding
22 over their entire surface from the 2060s2070s to 2090s under RCP8.5, although future reef growth may
23 delay the onset of flooding (limited evidence, low agreement) {15.3.3.1.1}.
24
25 Modelling of both temperature and ocean acidification effects under future climate scenarios (RCP 4.5
26 and RCP 8.5) suggest that some small islands will experience severe coral bleaching on an annual basis
27 before 2040 (medium confidence). Above 1.5°C, globally inclusive of small islands, it is projected there
28 will be further loss of 7090% of reef-building corals, with 99% of corals being lost under warming of 2°C
29 or more above the pre-industrial period. Intact coral reefs, seagrass meadows and mangroves provide a
30 variety of ecosystem services that are important to island communities (high confidence). These include
31 provisioning services regulating services, cultural services and those that support community resilience (high
32 confidence). If coastal ecosystems are degraded and lost, then the benefits they provide cannot be easily
33 replaced (medium confidence) {15.3.3.1.3, 15.3.3.1.4}.
34
35 Projected changes in aridity are expected to impose freshwater stress on many small islands, especially
36 SIDS (high confidence). It is estimated that with a warming of 1.5°C or less, freshwater stress on small
37 islands would be 25% less as compared to 2.0°C. While some island regions are projected to experience
38 substantial freshwater decline, an opposite trend is observed for some western Pacific and northern Indian
39 Ocean islands. Drought risk projections for Caribbean SIDS aligned with observations from the Shared
40 Socio-Economic Pathway (SSP) 2 scenario, indicate that a 1°C increase in temperature (from 1.7°C to
41 2.7°C) could result in a 60% increase in the number of people projected to experience a severe water
42 resources stress from 20432071. In some Pacific atolls, freshwater resources could be significantly affected
43 by a 0.40 m SLR. Similar impacts are anticipated for some Caribbean countries with worst-case scenario
44 (RCP8.5) indicating a 0.5-m SLR by the mid-century (2046-2065) and 1-m SLR by the end-of-century
45 (2081-2100). In SIDS with high projected population growth rates, they are expected to experience the most
46 severe freshwater stress by 2030 under a 2°C warming threshold scenario {15.3.3.2}
47
48 The continued degradation and transformation of terrestrial and marine ecosystems of small islands
49 due to human-dominated will amplify the vulnerability of island peoples to the impacts of climate
50 change (high confidence). New studies highlight large population reductions with an extinction risk of 100%
51 for endemic species within insular biodiversity hotspots including within the Caribbean, Pacific and
2
In this Report, the following terms have been used to indicate the assessed likelihood of an outcome or a result:
Virtually certain 99100% probability, Very likely 90100%, Likely 66100%, About as likely as not 3366%,
Unlikely 033%, Very unlikely 010%, and Exceptionally unlikely 01%. Additional terms (Extremely likely: 95
100%, More likely than not >50100%, and Extremely unlikely 05%) may also be used when appropriate. Assessed
likelihood is typeset in italics, e.g., very likely). This Report also uses the term `likely range' to indicate that the
assessed likelihood of an outcome lies within the 17-83% probability range.
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1 Suandaland regions by 2100 for > 3°C warming {15.3.3.3}. This is likely to decrease the provision of resources
2 (e.g. potable water) to the millions of people living on small islands, resulting in impacts upon settlements and
3 infrastructure, food and water security, health, economies, culture, and migration (high confidence) {15.3.3.2,
4 15.3.3.3, 15.3.4.1, 15.3.4.2, 15.4.3, 15.3.4.4, 15.3.4.5, 15.3.4.6, 15.3.4.7}.
5
6 Reef island and coastal area habitability in small islands is expected to decrease because of increased
7 temperature, extreme sea levels and degradation of buffering ecosystems, which will increase human
8 exposure to sea-related hazards (high confidence). Climate and non-climate drivers of reduced habitability
9 are context specific. On small islands, coastal land loss attributable to higher sea level, increased extreme
10 precipitation and wave impacts, and increased aridity have contributed to food and water insecurities that are
11 likely to become more acute in many places (high confidence). In the Caribbean, additional warming by
12 0.2°1.0°C, could lead to a predominantly drier region (5%15% less rain than present-day), a greater
13 occurrence of droughts along with associated impacts on agricultural production and yield in the region.
14 Crop suitability modelling on several commercially important crops grown in Jamaica found that even an
15 increase less than +1.5 °C could result in a reduction in the range of crops that farmers may grow. Most
16 Pacific Island Countries could experience 50% declines in maximum fish catch potential by 2100 relative
17 to 19802000 under both an RCP 2.6 and RCP 8.5 scenario {15.3.4.3, 15.3.4.4}.
18
19 Future Risks
20
21 The reduced habitability of small islands is an overarching significant risk caused by a combination of
22 several Key Risks facing most small islands even under a global temperature scenario of 1.5 degrees
23 (high confidence). These are loss of marine and coastal biodiversity and ecosystem services; submergence
24 of reef islands); loss of terrestrial biodiversity and ecosystem services ; water insecurity ; destruction of
25 settlements and infrastructure ; degradation of health and well-being ; economic decline and livelihood
26 failure); and loss of cultural resources and heritage. Climate-related ocean changes, including those for slow
27 onset events, and changes in extreme events are projected to cause and/or amplify Keys Risks in most small
28 islands. Identification of Key Risks facilitates the selection of optimal context-specific adaptation options.
29 Moreover, it can distil the benefits and/or disadvantages and long-term implications of choosing such options
30 (high confidence) {15.3.4.9}.
31
32 The vulnerability of communities in small islands, especially those relying on coral reef systems for
33 livelihoods, may exceed adaptation limits well before 2100 even for a low greenhouse gas emission
34 pathway (high confidence). The impacts of climate change on vulnerable low-lying and coastal areas,
35 present serious threats to the ability of land to support human life and livelihood's (high confidence).
36 Climate-related migration is expected to increase, although the drivers and outcomes are highly context-
37 specific and insufficient evidence exists to estimate numbers of climate-related migrants now and in the
38 future (medium evidence, high agreement) {15.3.4.1, 15.3.4.6, CCB7-1}.
39
40 Small islands are already reporting loss and damage particularly from tropical cyclones and increases
41 in sea-level rise (high confidence). Despite the loss of human life and economic damage the methods and
42 mechanisms to assess climate-induced loss and damage remain largely undeveloped for small islands.
43 Further, there are no robust methodologies to infer attribution and such assessments are limited. A research
44 gap on loss and damage includes how to assess the economic costs of loss and damage. Specific data on
45 experienced loss and damage across socio-economic groups and demographics are needed. Monitoring and
46 tracking slow onset events are equally important and require robust data {15.7, 15.8}.
47
48 Options, Limits and Opportunities of Adaptation
49
50 Some island communities are resilient with strong social safety nets and social capital that support
51 responses and actions already occurring, but there is limited information on the effectiveness of the
52 adaptation practices and the scale of needed action (high confidence). This is in part due to a need for a
53 better understanding of the limits to adaptation and of what constitutes current resilience and/or successful
54 adaptation in small island contexts. Greater insights into which drivers weaken local and indigenous
55 resilience, together with recognition of the socio-political contexts within which communities operate, and
56 the processes by which decisions are made, can assist in identifying opportunities at all scales to enhance
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1 climate adaptation and enable action towards climate resilient development pathways (medium evidence,
2 high agreement) {15.6.1, 15.6.5, 15.7}.
3
4 In small islands, despite the existence of adaptation barriers several enablers can be used to improve
5 adaptation outcomes and to build resilience (high confidence). These enablers include better governance
6 and legal reforms; improving justice, equity and gender considerations; building human resource capacity;
7 increased finance and risk transfer mechanisms; education and awareness programmes; increased access to
8 climate information; adequately downscaled climate data and embedding Indigenous Knowledge and Local
9 Knowledge (IKLK) as well as integrating cultural resources into decision-making (high confidence) {15.6.1
10 15.6.3, 15.6.4, 15.6.5}.
11
12 Small islands present the most urgent need for investment in capacity building and adaptation
13 strategies (high confidence) but face barriers and constraints which hinder the implementation of
14 adaptation responses. Barriers and constraints arise from governance arrangements, financial resources and
15 human resource capacity. Additionally, institutional and legal systems are often inadequately prepared for
16 managing adaptation strategies such as large-scale settlement relocation and other planned and/or
17 autonomous responses to climate risks (high confidence). Adaptation strategies are already being
18 implemented on some small islands although barriers are encountered including inadequate up-to-date and
19 locally relevant information, limited availability of finance and technology, lack of integration of IKLK in
20 adaptation strategies, and institutional constraints (high confidence) {15.5.3, 15.5.4, 15.6.3, 15.6.4, 15.6.5}.
21
22 For many small islands, adaptation actions are often incremental and do not match the scale of
23 extreme or compounding events (high confidence). Much of the currently implemented adaptation
24 measures remain small in scale (e.g., community-based adaptation projects), sectoral in focus and do not
25 address the needed structural and system level adaptations to combat climate impacts and achieve long term
26 sustainability of adaptation interventions. To address these shortcomings enablers are being integrated into
27 National Adaptation Plans and Disaster Risk Reduction Plans (high confidence) {15.6.3}.
28
29 Although international climate finance has increased in magnitude small islands face challenges in
30 accessing adaptation finance to cope with slow and rapid onset events (high confidence). In the
31 Caribbean, 38% of flows were concessional loans and 62% were grants whereas in the Atlantic and Indian
32 Oceans nearly 75% of the flows were in the form of concessional loans and 25% were grants. Solutions to
33 these barriers are being explored and some small islands have started adopting enablers such as insurance
34 and microfinance at both the national and local levels in responding to adaptation needs and to facilitate
35 resiliency building. COVID-19 has caused, however, economic shock in many small islands which will limit
36 adaptation, undermine the attainment of Sustainable Development Goals and slow down climate resilient
37 development transitions {15.8.3}.
38
39 The unavailability of up-to-date baseline data and contrasting scenarios/temperature levels continue
40 to impair the generation of local-to-regional observed and projected impacts for small islands,
41 especially those that are developing nations (high agreement). Climate model data based on the most
42 recent suite of scenarios (RCPs and especially SSPs) are still not widely available to primary modelling
43 communities in most small island developing nations (high agreement). Coastal sites of small islands are not
44 well-represented in global gridded population and elevation datasets, thereby making estimation of
45 population exposure to SLR difficult. The lack of data continues to impede the development of robust
46 impacts-based modelling output (e.g. for terrestrial biodiversity). Downscaling is pivotal for small islands
47 due to their high diversity which makes generalisation invalid.
48
49
50
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1 15.1 Introduction
2
3 This chapter examines the climate change impacts and projected risks faced by small islands, including the
4 detection and attribution of observed impacts, the loss and damage they experience, and the enablers, limits
5 and barriers to the implementation of adaptation options applicable to them. The implications of climate
6 change impacts on the attainment of the Sustainable Development Goals (SDGs), the need for more climate-
7 resilient development pathways based on a systems transitions approach, and how both of these intersect
8 with future potential responses are assessed within the context of small island states.
9
10 The small islands covered in this chapter are located within the tropics of the southern, northern, and western
11 Pacific Ocean, the central, eastern and western Indian Ocean, the Caribbean Sea, the eastern Atlantic off the
12 coast of West Africa, and in the temperate Mediterranean Sea. In contrast to the Intergovernmental Panel on
13 Climate Change (IPCC) Fifth Assessment Report (AR5), non-sovereign island states and territories
14 dependent on continental states and islands of semi-autonomous, sub-national island jurisdictions are
15 included in this chapter. Further, Small Island Developing States (SIDS) consisting of 39 small island and
16 low-lying coastal developing states which belong to the Alliance of Small Island States (AOSIS) are covered
17 in this assessment. Islands in the polar and sub-polar regions, North Atlantic Ocean, the Baltic Sea, the North
18 Sea, the Black Sea and the Arctic Ocean are not included.
19
20 Small islands share similarities such as geographical remoteness, isolation, narrow resource bases, heavy
21 dependency on external trade, vulnerability to exogenous economic shocks, economic volatility, and limited
22 access to development finance. Many are biodiversity hotspots and experience a disproportionate impact of
23 natural hazards associated with climate change. They are also diverse in physical and biophysical
24 characteristics, economic systems, political/governance systems, and exhibit social and cultural differences.
25 Adaptation responses vary among small islands because such diversity requires place-specific and culturally-
26 specific adaptation responses.
27
28 The chapter is structured in accordance with the overall format of the AR6 Working Group II report (Figure
29 15.1). This section presents points of departure from AR5 and IPCC (Section 15.2). As shown in Figure
30 15.1, this is followed by an assessment of current and future risks that are expected to be experienced by
31 small islands (Sections 15.3 and 15.4), what measures have been implemented (Section 15.5) and enablers,
32 limits and barriers that are being encountered (Section 15.6). Section 15.7 deals with the SDGs, climate-
33 resilient development pathways and potential future responses. The chapter ends with an identification of
34 research gaps (Section 15.8).
35
36
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1
2 Figure 15.1: Schematic illustration of the interconnections of Chapter 15 themes, including on observed impacts and
3 projected risks (Section 15.3) and on adaptation options and their implementation (Sections 15.5 and 15.6).
4
5
6 15.2 Points of Departure from AR5
7
8 Points of departure from AR5 are highlighted in this section in relation to exposure, vulnerability, impacts and
9 risks (Section 15.2.1), and adaptation options (Section 15.2.2).
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1
2 15.2.1 Points of Departure on Exposure, Vulnerability, Impacts and Risks
3
4 Scientific studies since AR5 confirm that global temperature will continue to increase even if greenhouse gas
5 emissions are drastically reduced and will escalate the vulnerability, impacts and multiple interrelated risks
6 experienced by small islands (high confidence) (IPCC, 2018). A greater sense of urgency in lowering global
7 greenhouse gas emissions and a call for action now is resonating among small island states.
8
9 Post-AR5 new studies confirm observed impacts on the natural and human systems and indicate projected
10 risks in both these systems over time. Over the past four decades, there was a significant increase in the
11 probability of the global exceedances of tropical cyclones (TCs) of major intensity (Kossin et al., 2020), a
12 trend confirmed by the occurrence of a growing number of intense TCs affecting the Atlantic and Pacific
13 regions since AR5 (Magee et al., 2016; Bhatia et al., 2019; Knutson et al., 2019). Since AR5 also scientific
14 evidence has confirmed that tropical corals are presently at high risk (very high confidence) and if global
15 warming exceeds 1.5°C, known coral reef restoration options may be ineffective (IPCC, 2018). Even
16 achieving emissions reduction targets consistent with the ambitious goal of 1.5°C of global warming under
17 the Paris Agreement will result in the further loss of 7090% of reef-building corals compared to today, with
18 99% of corals being lost under warming of 2°C or more above the pre-industrial period (high confidence)
19 (Hoegh-Guldberg et al., 2018).
20
21 Additionally, since the last assessment more robust scientific evidence exists on the impacts of sea level rise
22 (SLR) and extreme sea level events (ESL) on small islands. Under Representative Concentration Pathways
23 emission scenarios, RCP2.6, RCP4.5 and RCP8.5, many low-lying coastal areas at all latitudes, including
24 small islands, will experience SLR and ESL events such as coastal storm surges and coastal flooding more
25 frequently in the coming decades (Section 4.2.3.4.1; IPCC, 2019 ). SLR and ESL events will affect atoll
26 islands and islands with higher elevations differently. New studies forecast that small islands are likely to
27 experience some of the largest increases in endemic extinctions and may substantially contribute to future
28 global biodiversity loss, as well as to impaired ecosystem functioning (Fortini et al., 2015; Vogiatzakis et al.,
29 2016; Cramer et al., 2018). Scientific evidence points to large population reductions with an extinction risk
30 of 100% for endemic species within insular biodiversity hotspots by 2100 (IPBES, 2018; Manes et al.,
31 2021). An overarching concern since AR5 is the reduced habitability of small islands. Eight key risks
32 affecting the habitability of small islands are identified in this assessment and these are covered in the
33 pertinent sections of this chapter which assess adaptation responses.
34
35 15.2.2 Points of Departure on Adaptation
36
37 New knowledge of adaptation responses used in small islands has grown significantly since AR5. Strategies
38 include hard protection, land reclamation and permanent relocation, with improved appreciation for when
39 each strategy is relevant (IPCC, 2019). Evidence of migration as an adaptation response to climate change
40 remains limited (Roland and Curtis, 2020). Understanding of ecosystem-based adaptation (EbA) has
41 improved considerably but there is medium agreement regarding its benefits (Doswald et al., 2014; Nalau et
42 al., 2018a) and limited evidence and low agreement on its economic efficiency and long-term effectiveness
43 (Renaud et al., 2016; Oppenheimer et al., 2019).
44
45 Since the previous assessment, integration of Indigenous Knowledge and Local Knowledge (IKLK) into
46 adaptation is recognized as a major benefit in preparing and recovering from TCs and EbA (Narayan et al.,
47 2020). The roles of social capital, health-related adaptation strategies and livelihood responses are more fully
48 understood (Nalau et al., 2018b; Nunn and Kumar, 2018; Abram et al., 2019; IPCC, 2019). Gender equity,
49 climate justice, climate services, early warning systems, and disaster risk reduction (Vaughan and Dessai,
50 2014; Newth and Gunasekera, 2018), which were data gaps in AR5, have received more treatment,
51 especially in the context of small islands. Stronger evidence confirms that education and awareness-raising
52 enhance household and community adaptation (high confidence).
53
54 Knowledge has improved on limits to adaptation, including projected timeframes of limits for hard
55 protection (high confidence) and EbA (medium confidence) (IPCC, 2019). There is also a better
56 understanding that barriers and governance challenges vary by island and island groups (high confidence)
57 and result in them having different adaptive capacities (IPCC, 2019). A major barrier to adaptation is limited
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1 information on the feasibility, outcomes and sustainability of adaptation responses in small islands.
2 Moreover, limited time series data on monitoring and evaluation make evaluating the feasibility of
3 adaptation responses difficult.
4
5 Adaptation financing for small islands has increased since AR5 although leveraging finance is a constraint
6 and remains complex (Robinson and Dornan, 2017). Informal microfinancing has grown and risk transfer
7 mechanisms are being explored although funding and access to insurance schemes is limited (Handmer and
8 Nalau, 2019; Nunn and Kumar, 2019a; Petzold and Magnan, 2019). In small islands the methods and
9 mechanisms to assess climate-induced loss or damage remain undeveloped (medium confidence) (Thomas
10 and Benjamin, 2017; Handmer and Nalau, 2019).
11
12 Many small islands have experienced economic shock arising from COVID-19 and have had to re-direct
13 investment previously targeting sustainable development (Sheller, 2020). Adaptation will be affected by
14 economic contraction and indebtedness. Framing adaptation within climate-resilient development pathways
15 (CRDPs) that emphasise systems transition and are implemented at scale may bolster small islands'
16 resilience to multiple shocks like COVID-19.
17
18
19 15.3 Observed Impacts and Projected Risks of Climate Change
20
21 Compared to larger landmasses, many climate change driven impacts and risks are amplified for small
22 islands. This is due largely to their boundedness (surrounded by ocean), their comparatively small land areas,
23 and often their remoteness from more populated parts of the world, which restricts the global connectivity of
24 islands. This is true on all types of islands (Figure 15.2).
25
26
27
28 Figure 15.2: Classification of small island types - showing island characteristics and elements of human exposure
29 (based on Nunn et al. (2016); Kumar et al. (2018)).
30
31
32 15.3.1 Synthesis of Observed and Projected Changes in the Physical Basis
33
34 There is increased evidence of warming in the small islands, particularly in the latter half of the 20th century
35 (high confidence). The diversity of metrics and timescales used across studies makes it impossible to provide
36 explicit comparisons, however Table 15.1 provides a summary of observed changes.
37
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1
2 Table 15.1: Observed changes in basic climate metrics. RSLR: Relative Sea-Level Rise
Phenomenon Location Basic Specific Metric Time Reference
Trends period Literature
Increase in daily mean minimum McGree et al.
Air temp West Pacific Warmer 1951-2015
temp by 0.14C/ decade (2019)
Increase in daily minimum temp Stephenson et
Air temp Caribbean Warmer 1961-2010
by 0.28C/ decade al. (2014)
Increase in annual mean surface Mariotti et al.
Air temp Mediterranean Warmer 1960-2005
temp 0.19-0.25C/ decade (2015)
Land & Sea Annual mean temperatures are (MedECC,
Mediterranean Warmer now 1.54°C above the 1860- 2020)
1890 level for land and sea
temp
Rainfall Mediterranean Drier Decrease in annual mean 1960-2005 Mariotti et al.
Rainfall precipitation by -0.6 (2015);
Rainfall mm/day/decade Ducrocq et al.
Rainfall (2016)
Drought No clear No significant long-term trends McGree et al.
Pacific Ocean
Drought 1951-2015
pattern
Tropical in rainfall (2019)
Cyclones
Tropical No clear Nguyen et al.
Cyclones Indian Ocean 1983-2015
Tropical
Cyclones pattern (2018)
Caribbean No clear No significant long-term trends
pattern Jones et al.
in rainfall in the Caribbean over 1901-2012
(2015)
the 20th century
Low Inconsistent between subregions Herrera and
confidence
Caribbean in the 1950-2016
direction of
change and not statistically significant Ault (2017)
Pacific Ocean Low Inconsistent between subregions 1951-2015 McGree et al.
confidence and not statistically significant (2016); McGree
in the in the tropical Pacific. et al. (2019)
direction of Significant decrease in Hawaii
change and sub-tropical South Pacific
North Atlantic Increase in Walsh et al.
intensity 1975-2009
and
decrease in (2016)
frequency
Western North Decreasing Decrease in frequency except Walsh et al.
1977-2010
Pacific frequency over central North Pacific.
(2016)
South Pacific Increase in 1989-2009 Walsh et al.
intensity (2016)
and Kuleshov et al.
decrease in (2020)
frequency
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Tropical No clear Poor data coverage 1961-2008 Tauvale and
Cyclones Indian Ocean Tsuboki (2019);
Kuleshov et al.
pattern (2020)
RSLR East Greater than Becker et al.
Caribbean 3-5mm/year 1993-2014
average (2019)
RSLR West/North Greater than Becker et al.
Caribbean 2.5-3mm/year 1993-2014
average (2019)
RSLR Western Greater than Becker et al.
Tropical 5-11mm/year 1993-2014
Pacific
average (2019)
Mauritius/ Greater than Becker et al.
1993-2014
RSLR 4mm/year
(2019)
Indian Ocean average
RSLR Rodrigues/ Greater than Becker et al.
6mm/year 1993-2014
Indian Ocean average (2019)
1
2
3 Some phenomena have no demonstrable trends in a region because of limited observed data, these include
4 Tropical Cyclone (TC) frequency in the North-Eastern Pacific and Indian Oceans (Walsh et al., 2016); other
5 phenomena are too variable to detect an overarching trend, including rainfall in regions where inter-annual
6 and decadal variabilities such as the El Niño-Southern Oscillation, North Atlantic Oscillation, Pacific
7 Decadal Variability, Atlantic Multidecadal Variability are dominant (Jones et al., 2015; McGree et al.,
8 2019).
9
10 There are also marked regional variations in the rates of Sea Level Rise (SLR) (Merrifield and Maltrud,
11 2011; Palanisamy et al., 2012; Esteban et al., 2019) and Relative (that is, incorporating land movement) Sea-
12 level Rise (RSLR). Various factors, including interannual and decadal sea level variations associated with
13 low frequency modulation of ENSO and the Pacific Decadal Oscillation (PDO) and vertical land motion
14 contribute to both relative sea-level variations and related uncertainties. Increased distant-source swell height
15 from extra-tropical cyclones (ETCs) also contributes to Extreme Sea Levels (ESLs) (Mentaschi et al., 2017;
16 Vitousek et al., 2017). Together, these stressors increase ESLs and their impacts, including coastal erosion
17 and marine flooding and their impacts on both ecosystems and ecosystem services and human activities
18 (Section 15.3.3.1 and Table 15.3).
19
20 Like observed impacts, projected impacts include some high confidence assessments, which are distributed
21 across a diversity of models, timescales, and metrics. Generalised trends, and specific projections when
22 available, are provided in Table 15.2. However, actual values and spatial distribution of precipitation
23 changes remain uncertain as they are strongly model dependent (Paeth et al., 2017). Furthermore, the current
24 capabilities of climate models, to adequately represent variability in climate drivers including ENSO, and the
25 topography of small islands, limit confidence in these future changes (Cai et al., 2015a; Harter et al., 2015;
26 Guilyardi et al., 2016).
27
28
29 Table 15.2: A small subset of projected changes in basic climate metric. Med=Mediterranean; NC=no change
30 [INSERT TABLE 15.2 HERE]
31
32
33 15.3.2 Trends in Exposure and Vulnerability
34
35 Most of the research that has been conducted on exposure and vulnerability from climate change
36 demonstrates that factors including those that are geopolitical and political, environmental, socio-economic
37 and cultural, together conspire to increase exposure and vulnerability of small islands (Box 15.1; Betzold,
38 2015; McCubbin et al., 2015; Duvat et al., 2017b; Otto et al., 2017; Weir et al., 2017; Taupo et al., 2018;
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1 Barclay et al., 2019; Hay et al., 2019a; Ratter et al., 2019; Salmon et al., 2019; Bordner et al., 2020;
2 Douglass and Cooper, 2020; Duvat et al., 2020a). Additional pressures on coastal and marine environments,
3 including overexploitation of natural resources, may further exacerbate possible impacts in the future (Bell et
4 al., 2013; Pinnegar et al., 2019; Siegel et al., 2019).
5
6 Furthermore, these factors exacerbate climate change induced problems such as coastal flooding and erosion
7 faced by small islands. These impacts continue to worsen, which put small islands at increasingly higher risk
8 to the impacts of climate change (Box 15.1). There are multiple stressors that affect the vulnerability of small
9 islands to climate change (McNamara et al., 2019).
10
11 The problems of increasing exposure and vulnerability is most clearly seen in atoll islands. For example, in
12 the capital of Tuvalu, economic stressors, food related stressors, and overcrowding make the islands much
13 more vulnerable to climate impacts including changing precipitation patterns, ESLs, intense strong winds,
14 warming SST and ocean acidification (McCubbin et al., 2015). Small islands, in trying to address the
15 problem of limited land availability, put in place practices that lead to increasing exposure for island people.
16 In Majuro, Marshall Islands (Ford, 2012), Tarawa, Kiribati (Biribo and Woodroffe, 2013; Duvat, 2013), and
17 the Maldives Islands (Kench, 2012; Naylor, 2015; Duvat and Magnan, 2019b), population growth has led to
18 land reclamation and the building of coastal protection structures, such as seawalls. Land reclamation and
19 coastal protection structures negatively impact coastal and marine ecosystems, including reefs and
20 mangroves, which compromise the protection services that they deliver to island communities through wave
21 energy attenuation and sediment supply (Gracia et al., 2018; Curnick et al., 2019; Duvat and Magnan, 2019a)
22 and may impact the long term sustainable adaptive planning of islands (Giardino et al., 2018). In addition,
23 these construction activities disrupt natural coastal processes, thereby causing coastal erosion, which in turn
24 increases the risk of flooding (Yamano et al., 2007; Duvat et al., 2017b) (Figure 15.3). This becomes a
25 vicious cycle, with more land reclamation necessary to accommodate growing populations. Land
26 reclamation requires stabilisation by protection structures, which then contributes to environmental
27 degradation that increases the exposure and vulnerability of the communities living in these atolls (Duvat et
28 al., 2017b).
29
30
31
32 Figure 15.3: Percentage of current population in selected small islands occupying vulnerable land (the number of
33 people on land that may be exposed to coastal inundation--either by permanently falling below MHHW, or temporarily
34 falling below the local annual flood height) in 2100 under an RCP4.5 scenario (adapted from Kulp and Strauss (2019)
35 using the CoastalDEM_Perm_p50 model). Positions on the map are based on the capital city or largest town.
36
37
38 15.3.3 Observed Impacts and Projected Risks on Natural Systems
39
40 15.3.3.1 Impacts on Marine and Coastal Systems
41
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1 15.3.3.1.1 Submergence and flooding of islands and coastal areas
2 Recent studies confirmed that observed ESL events causing extensive flooding generally resulted from
3 compound effects, including the combination of SLR (Section 3.2.2.2 and Cross-Chapter Box SLR in
4 Chapter 3) with ETCs, TCs and tropical depressions (WGI AR6 Sections 11.7.1 and 11.7.2), ENSO-related
5 high-water levels associated with high or spring tide and/or local human disturbances amplifying impacts
6 (high confidence). For example, the major floods that occurred in 1987 and 2007 in the Maldives involved
7 the combination of distant-source swells and high spring tides and the settlement of reclaimed low-lying
8 areas (Box 15.1; Wadey et al., 2017). In the Tuamotu atolls, French Polynesia, the 1996 and 2011 floods
9 were due to the combination of distant-source swells causing lagoon filling and the obstruction of inter-islet
10 channels by human-built structures (Canavesio, 2019). In 2011, the flooding of the lagoon-facing coast of
11 Majuro Atoll, Marshall Islands, resulted from the combination of high sea levels occurring during La Niña
12 conditions and seasonally high tides (Ford et al., 2018). Another example is the widespread flooding caused
13 by distant TC Pam (2015) in Kiribati and Tuvalu, which was attributed to the strong swell generated, the
14 long duration of the event and exceptionally high regional sea levels (Hoeke et al., 2021). On high tropical
15 islands, major floods often occurred during TC events, due to the cumulative effects of storm surge and river
16 flooding, the impacts of which were exacerbated by human-induced changes to natural processes in urban
17 areas. This for example occurred in 2014 (TC Bejisa) in Reunion Island, France, in a harbour area favourable
18 to water accumulation (Duvat et al., 2016); in 2015 (TC Pam) in Port Vila, Vanuatu, where urbanisation and
19 human-induced changes to the river exacerbated flooding (Rey et al., 2017); and in 2017 (TC Irma) in Saint-
20 Martin, Caribbean, where urbanisation had the same effect (Rey et al., 2019). Successive tropical
21 depressions generating heavy rains were also involved in extensive flooding, for example in 2012 in Fiji
22 (Kuleshov et al., 2014) and in 2014 in the Solomon Islands (Ha'apio et al., 2019).
23
24 Reconstructions of past storm surges and modelling studies assessing storm surge risk similarly highlighted
25 high variations of risk along island coasts, due to variations in exposure, topography and bathymetry (high
26 confidence). For example, the storm surge caused by TC Oli (2010) on the high volcanic island of Tubuai,
27 French Polynesia, ranged from a few centimetres to 2.5 m, depending on coast exposure (Barriot et al.,
28 2016). Investigating the contribution of reef characteristics to variations in wave-driven flooding on Roi-
29 Namur Island, Kwajalein Atoll, Marshall Islands, (Quataert et al., 2015) found that the coasts fronted by
30 narrow reefs with steep fore reef slopes and smoother reef flats are the most flood-prone. Modelling studies
31 assessing storm surge risk in Fiji (McInnes et al., 2014) and Samoa (McInnes et al., 2016) confirmed the
32 influence of coast exposure and water depth on risk distribution. In Apia, Samoa, Hoeke et al. (2015, p.
33 1117) found "differences in extreme sea levels in the order of 1 m at spatial scales of less than 1 km" and
34 estimated (p. 1131) that a "1 m SLR relative to constant topography increases wave energy reaching the
35 shore by up to 200% during storm surges." These studies reaffirmed the main control exerted by SLR on
36 ESL events and associated storm surges compared to ENSO (high confidence). In Hawaii and the Caribbean,
37 SLR is projected to exponentially increase flooding, with nearly every centimeter of SLR causing a doubling
38 of the probability of flooding (Taherkhani et al., 2020). Simulations of SLR-induced flooding resulting from
39 the combination of (i) direct marine flooding, (ii) flow reversal in drainage networks caused by extreme tide
40 levels and (iii) the elevation of groundwater levels, at Honolulu, Hawaii, highlighted the major influence of
41 this latter component (which is the most difficult to manage), as well as the increase of the proportion of
42 triple-mechanism flooding as sea level rises (Habel et al., 2020). Where coral reefs buffer flooding through
43 wave attenuation, flooding will be further aggravated by reef decline over time (Section 15.3.3.1.3).
44
45 Larger-scale studies confirmed that projected changes in the wave climate superimposed on SLR will rapidly
46 increase flooding in small islands, despite highly contrasting exposure profiles between ocean sub-regions
47 (high confidence) (Shope et al., 2016; Mentaschi et al., 2017; Shope et al., 2017; Vitousek et al., 2017;
48 Morim et al., 2019). In particular, Vitousek et al. (2017) showed that even a 5-10 cm additional SLR
49 (expected for ~20302050) will double flooding frequency in much of the Indian Ocean and Tropical
50 Pacific, while TCs will remain the main driver of (rarer) flooding in the Caribbean Sea and Southern
51 Tropical Pacific (Figure 15.3). Some Pacific atoll islands, which already experience major floods, will likely
52 undergo annual wave-driven flooding over their entire surface from the 2060s2070s (Storlazzi et al., 2018)
53 to 2090s (Beetham et al., 2017) under RCP8.5, although future reef growth may delay the onset of flooding
54 (limited evidence, low agreement) (Key Risk KR2 in Figure 15.5).
55
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1 15.3.3.1.2 Reef island destabilisation and coastal erosion
2 Over the past three to five decades, shoreline changes were dominated by stability on reef islands and
3 erosion on high islands; attribution of observed erosion to SLR and other climate change-related drivers is
4 challenged by the complex interplay of multiple climatic, ecological and human drivers (high confidence).
5 Since the 1950s-1970s, and even in regions exhibiting higher than global averaged SLR rates, atoll islands
6 maintained their land area (high confidence). A literature review including 709 Indian and Pacific Oceans
7 atoll islands showed that 73.1% of these islands were stable in area, while respectively 15.5% and 11.4%
8 increased and decreased in area (Duvat, 2018). The rates of change did not correlate with SLR rates,
9 suggesting that the impact of SLR on island land area was obscured by other climate drivers and human
10 disturbances on some islands (high confidence) (Kench et al., 2015; McLean and Kench, 2015; Duvat,
11 2018). However, reef island disappearance and reduction in land area was clearly observed in New
12 Caledonia and the Solomon Islands, and was attributed to the synergistic interactions of gradual SLR with
13 stronger trade winds causing higher sea levels and local tectonics in the Solomon Islands (Albert et al., 2016;
14 Garcin et al., 2016). Despite important knowledge gaps on coastal erosion in high tropical islands, recent
15 studies confirmed increasing shoreline retreat and beach loss over the past decades, mainly due to TC and
16 ETC waves and human disturbances (high confidence) (e.g., in the Caribbean region: Anguilla, Saint-Kitts,
17 Nevis, Montserrat, Dominica and Grenada (Cambers, 2009; Reguero et al., 2018)), and Pacific (Hawaii
18 (Romine and Fletcher, 2013); Tubuai, French Polynesia (Salmon et al., 2019)) and Indian Oceans (Anjouan,
19 Comoros (Ratter et al., 2016)).
20
21 Despite storm-induced erosion prevailing along some shoreline sections, recent studies reaffirmed the
22 contribution of TC and ETC waves to coastal and reef island vertical building through massive reef-to-island
23 sediment transfer (high confidence). For example, TC Ophelia (1958) and Category 5 TC Fantala (2016),
24 which respectively eroded the islands of Jaluit Atoll, Marshall Islands (Ford and Kench, 2016), and Farquhar
25 Atoll, Seychelles (Duvat et al., 2017c), also contributed to island and beach expansion. Likewise, tropical
26 depressions can have constructional effects, as reported on Fakarava Atoll, French Polynesia (Duvat et al.,
27 2020b). On Saint-Martin/Sint Maarten and Saint-Barthélemy, the 2017 hurricanes, which caused marked
28 shoreline retreat at most beach sites, also allowed beach formation and beach ridge development along some
29 natural coasts (Duvat et al., 2019a; Pillet et al., 2019). Similarly, El Niño and La Niña were involved in rapid
30 and highly contrasting shoreline changes (high confidence), including reef island accretion in the Ryukyu
31 Islands, Japan (Kayanne et al., 2016), beach shifts on Maiana and Aranuka Atolls, Kiribati (Rankey, 2011),
32 and beach erosion on Hawaii, USA (Barnard et al., 2015). These contrasting shoreline responses were
33 respectively due to coral reef degradation from past bleaching events providing material to islands, wave
34 directional shifts, and increased wave energy. The role of bleaching events in increasing short-term sediment
35 generation in atoll contexts was confirmed by a study conducted on Gaafu Dhaalu Atoll, Maldives, which
36 reported an increase of sediment production from ~0.5 kg CaCO3 m2 yr-1 to ~3.7 kg CaCO3 m-2 yr-1
37 between 2016 (pre-bleaching) and 2019 (bleaching + 3 years) (Perry et al., 2020).
38
39 There is high confidence that accelerating SLR and increased wave height will affect the geomorphology of
40 reef islands (Baldock et al., 2015; Costa et al., 2019; Tuck et al., 2019) and coastal systems on high islands
41 (Grady et al., 2013; Barnard et al., 2015; Bindoff et al., 2019), and that the responses of these systems will
42 highly depend on changes in boundary conditions (wave regime and direction, exposure to extreme events,
43 impacts of ocean warming and acidification on supporting ecosystems, bathymetry and reef flat roughness)
44 and the degree of disturbance of their natural dynamics by human activities (Smithers and Hoeke, 2014;
45 McLean and Kench, 2015; Bheeroo et al., 2016; Ratter et al., 2016; Shope et al., 2016; Duvat et al., 2017a;
46 Kench and Mann, 2017; Kench et al., 2018; Duvat et al., 2019a). Reef islands and beach and beach-dune
47 systems that are not disturbed by human activities are respectively expected to migrate lagoonward (Webb
48 and Kench, 2010; Albert et al., 2016; Beetham et al., 2017; Costa et al., 2019; Tuck et al., 2019) and
49 landward (Bindoff et al., 2019), and to also experience increased erosion as well as changes in configuration,
50 volume and elevation (Kench and Mann, 2017; Tuck et al., 2019) (Bramante et al., 2020; Kane and Fletcher,
51 2020). Small reef islands and narrow coastal systems affected by human disturbances will increasingly be at
52 risk of disappearance due to SLR (KR2 in Figure 15.5), enhanced sediment loss caused by extreme events
53 (Duvat et al., 2019a) and/or human activities (high confidence), as reported in Hawaii (Romine and Fletcher,
54 2013), Puerto Rico (Jackson et al., 2012), Sicily (Anfuso et al., 2012), and Takuu, Papua New Guinea (Mann
55 and Westphal, 2014). SLR will also increase coastal erosion in the Mediterranean Sea, (e.g., in the Aegean
56 Archipelago, Greece (Monioudi et al., 2017)), and Mallorca, Spain (Enríquez et al., 2017).
57
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1 15.3.3.1.3 Impacts on marine and coastal ecosystems
2 Loss of marine and coastal biodiversity and ecosystem services is a Key Risk in small islands (see KR1 in
3 Figure 15.5). Coral bleaching caused by elevated water temperatures is the most visible and widespread
4 manifestation of a climate change impact on coastal ecosystems in most small islands but is far from being
5 the only one (Section 3.4.2.1; Section 5.3.4; Spalding and Brown, 2015; Hoegh-Guldberg et al., 2017; IPCC,
6 2018; Bindoff et al., 2019; Sully et al., 2019). Severe coral bleaching, together with declines in coral
7 abundance have been documented in many small islands, especially those in the Pacific and Indian
8 Oceans,(e.g., Guam, Fiji, Palau, Vanuatu, Chagos, Comoros, Mauritius, Seychelles, and the Maldives (high
9 confidence) (Box 15.1; Golbuu et al., 2007; Woesik et al., 2012; Perry and Morgan, 2017; Hughes et al.,
10 2018). During severe bleaching events, not only do reefs lose a significant amount of live coral cover, but
11 they also experience a decrease in growth potential, so reef erosion surpasses reef accretion (Perry and
12 Morgan, 2017). Median return time between two severe bleaching events has diminished steadily since 1980
13 and is now only 6 years (e.g.,Hughes et al., 2017b; Hughes et al., 2018) and is often associated with warm
14 phase of ENSO events (high confidence) (Lix et al., 2016). Modelling of both bleaching and ocean
15 acidification effects under future climate scenarios suggested that some Pacific small islands (e.g., Nauru,
16 Guam, Northern Marianas Islands) will experience conditions that cause severe bleaching on an annual basis
17 before 2040 and that 90% of the world reefs are projected to experience conditions that result in severe
18 bleaching annually by 2055 (medium confidence) (van Hooidonk et al., 2016). Models are currently
19 predicting the large-scale loss of coral reefs by mid-century under even low-emissions scenarios. Even
20 achieving emissions reduction targets consistent with the ambitious goal of 1.5°C of global warming under
21 the Paris Agreement will result in the further loss of 7090% of reef-building corals compared to today, with
22 99% of corals being lost under warming of 2°C or more above the pre-industrial period (high confidence)
23 (Hoegh-Guldberg et al., 2018).
24
25 Satellite data and local field studies at 3351 sites in 81 countries including small islands show that not all
26 coral reefs are equally exposed to severe temperature stress events, and even similar coral reefs exposed to
27 similar conditions show local and regional variation and species-specific responses (Sully et al., 2019). There
28 is great variability in terms of sensitivity of corals to climate change, as also demonstrated in the Comoros
29 Archipelago (Cowburn et al., 2018), in the Pacific (Fox et al., 2019; Mollica et al., 2019; Romero-Torres et
30 al., 2020) and globally (Sully et al., 2019; McClanahan et al., 2020). It has been hypothesised that low-
31 latitude tropical reefs bleached less than those in higher latitudes because: (i) of the geographical differences
32 in species composition, (ii) of the higher genotypic diversity at low latitudes, and (iii) some corals were pre-
33 adapted to thermal stress because of consistently warmer temperatures at low latitude prior to thermal stress
34 events (Sully et al., 2019). However, latitudinal variation was not reported in other global surveys of coral
35 bleaching occurrence (Donner et al., 2017; Hughes et al., 2017a; Hughes et al., 2017b; McClanahan et al.,
36 2019). Ainsworth et al. (2016) and Ateweberhan et al. (2013) showed that coral bleaching can be mitigated
37 by pre-exposure to elevated temperatures. Regionally, recovery is also highly variable. While some reefs in
38 the Seychelles and Maldives were shown to recover to pre-disturbance levels of coral cover after previous
39 bleaching events (Box 15.1; Pisapia et al., 2016; Koester et al., 2020), other reefs underwent seemingly
40 permanent regime shifts toward domination by fleshy macro algae (Graham et al., 2015), or major declines
41 in carbonate budgets, and thus the capacity of reefs to sustain vertical growth under rising sea levels (Perry
42 and Morgan, 2017).
43
44 Despite their vital social and ecological value, substantial declines in seagrass communities have been
45 documented in many small islands (Section 3.4.2.5; Arias-Ortiz et al., 2018; Kendrick et al., 2019; Brodie et
46 al., 2020), including Fiji (Joseph et al., 2019), Reunion Island (Cuvillier et al., 2017), Bermuda, Cayman
47 Islands, US Virgin Islands (Waycott et al., 2009), Kiribati (Brodie et al., 2020), Federated States of
48 Micronesia, and Palau (Short et al., 2016), but attribution of such declines to climatic influences remains
49 weak (low confidence). Impact of climate change on seagrasses goes beyond the loss of seagrass but includes
50 acceleration of seagrass decomposition (Kelaher et al., 2018), palatability (Jimenez-Ramos et al., 2017) and
51 the cumulative effect of warming and eutrophication (Ontoria et al., 2019). Seagrasses face a multitude of
52 threats including physical disturbance and direct damage caused by rapidly growing human populations,
53 declines in water quality, and coastal erosion (Short et al., 2016). Experimental studies have shown increased
54 mortality, leaf necrosis, and respiration when seagrasses are exposed to higher-than-normal temperatures
55 (Hernan et al., 2017). As such, seagrass meadows growing near the edge of their thermal tolerance are at risk
56 from rising temperatures (Pedersen et al., 2016). In the Mediterranean, seagrass meadows are already
57 showing signs of regression, which may have been aggravated by climate change (high confidence). Some
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1 studies suggest seagrasses have potential for acclimation and adaptation (Duarte et al., 2018; Ruiz et al.,
2 2018; Beca-Carretero et al., 2020). Chefaoui et al. (2018) attempted to forecast the distribution of two
3 seagrasses in the future, including around the islands of Cyprus, Malta, Sicily and the Balearic Islands.
4 Under the worst-case scenario, Posidonia oceanica was projected to lose 75% of suitable habitat by 2050.
5 Conversely, it has been suggested that seagrasses could actually benefit from an increase in anthropogenic
6 carbon dioxide because of increased growth and photosynthesis (Hopley et al., 2007; Waycott et al., 2011;
7 Sunday et al., 2016; Repolho et al., 2017). However, Collier et al. (2017) argued that when faced with
8 increased heat waves, thermal stress will rarely be offset by the benefit of elevated CO2 and therefore that
9 the widespread belief that seagrasses will be a `winner' under future climate change conditions seems
10 unlikely (low confidence).
11
12 Since 2011, the Caribbean region has been experiencing unprecedented influxes of the pelagic seaweed
13 Sargassum. These extraordinary sargassum `blooms' have resulted in mass strandings of sargassum
14 throughout the Lesser Antilles, with significant damage to coastal habitats, mortality of seagrass beds and
15 associated corals (van Tussenbroek et al., 2017), as well as consequences for fisheries and tourism. Whether
16 or not such events are related to long-term climate change remains unclear, however it has been suggested
17 that the influx may be related to strong Amazon discharge, enhanced West African upwelling, together with
18 rising seawater temperatures in the Atlantic (low confidence) (Oviatt et al., 2019; Wang et al., 2019). Since
19 2011, the Pacific atoll nation of Tuvalu has also been affected by algal blooms, the most recent being a large
20 growth of Sargassum on the main atoll of Funafuti, and this phenomenon has been related to anthropogenic
21 eutrophication and high seawater temperatures (De Ramon N'Yeurt and Iese, 2014).
22
23 Mangroves face serious risks from deforestation and unsustainable coastal development (Section 3.4.2.5;
24 Gattuso et al., 2015). Large-scale die-offs around many small islands suggest that mangrove face increased
25 risks from climate change (Sippo et al., 2018). Mangrove seaward edge retreat has been demonstrated in
26 American Samoa and at Tikina Wai in Fiji, in Bermuda, West Papua, Grand Cayman and attributed to long-
27 term SLR or tectonic subsidence (Ellison, 1993; Ellison, 2005; Gilman et al., 2007; Ellison and Strickland,
28 2015). Inundation-related mortality of mangroves could, in theory, be mitigated if mangrove substrates can
29 "keep up" with rising sea level by accretion. Pacific Island studies using radionuclides (e.g., 210Pb, 137Cs)
30 have suggested that most mangroves are keeping up with current rates of sea level rise (Alongi, 2008;
31 MacKenzie et al., 2016), while surface elevation tables SETs suggest otherwise. Lovelock et al. (2015)
32 reported that nearly 70% of the mangroves monitored with SETs are not keeping up with current SLR rates.
33 If SLR exceeds 6 mm/yr, mangroves may be unable to maintain their elevation relative to sea level, a
34 threshold likely to be surpassed in the next 30 years under high emission scenarios (Ellison, 1993; Saintilan
35 et al., 2020). In these worst-case scenarios, flooding would result in tree, root, and rhizome death and an
36 abrupt change in elevation through peat collapse (Krauss et al., 2010; Lang'at et al., 2014), creating a
37 positive feedback loop between SLR and elevation loss. Geomorphology, hydrology, tidal range, and
38 suspended sediments are important factors that will determine if mangroves will survive increased rates of
39 SLR (Lovelock et al., 2015; Sasmito et al., 2015; Rogers et al., 2019). TCs can cause extensive damage to
40 mangroves (Short et al., 2016). While immediate physical damage is often considerable, trees can sometimes
41 recover by re-foliating, re-sprouting or regenerating (Kauffman and Cole, 2010). Examples of substantive
42 mangrove recovery include the regrowth of trees in the Bay Islands of Honduras following Hurricane Mitch
43 (October 1998) (Fickert, 2018) and in the Nicobar Islands, India, following the December 2004 Indian
44 Ocean Tsunami (Nehru and Balasubramanian, 2018).
45
46 Sandy beaches are an important ecosystem in small islands, with high socio-economic as well as ecosystem
47 services value (Ellison, 2018). Turtles and many seabirds nest just above the high-water mark on sandy
48 beaches or among sand dunes, but TCs, rising seas, storm surges and heavy rainfall as well as inappropriate
49 coastal development can erode beaches (Section 15.3.1.2) resulting in damage to nests and eggs (Fuentes et
50 al., 2011). Beach-nesting turtle populations are projected to become threatened around many small islands as
51 a result of future climate change (e.g., Bonaire - Netherlands Antilles (Fish et al., 2005), Bioko Island -
52 Equatorial Guinea (Veelenturf et al., 2020), Cyprus (Varela et al., 2019), Raine Island Australia (Pike et
53 al., 2015)), although other populations such as those around the Cape Verde Islands are projected to remain
54 relatively robust (Abella Perez et al., 2016). Turtles are also threatened by temperature rise around some
55 small islands as warmer temperatures on nesting beaches can lead to an unbalanced sex-ratio in the
56 population (e.g. St. Eustatius island, (Laloë et al., 2016)).
57
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1 15.3.3.1.4 Marine and coastal ecosystem services
2 Intact coral reefs (Woodhead et al., 2019), seagrass meadows (Hejnowicz et al., 2015), and mangroves
3 (UNEP, 2014b) (Friess, 2016) provide a variety of ecosystem services that are key to island communities,
4 including provisioning services (e.g., timber, fisheries, aquaculture), regulating services (e.g., coastal
5 protection, carbon storage, filtering of pollutants), cultural services (Pascua et al., 2017) as well as
6 supporting community resilience (Förster et al., 2019). If coastal ecosystems are degraded and lost, then the
7 benefits they provide are also lost (Oleson et al., 2018; Förster et al., 2019; Brodie et al., 2020). In small
8 islands where the risk of loss to ecosystem services is high (Cross-Chapter Box DEEP in Chapter 17), many
9 of these ecosystem services cannot be easily replaced (medium confidence). The beneficial role that coral
10 reefs play in coastal protection through wave attenuation, and therefore enhancing climate resilience in small
11 islands, has been extensively studied (e.g., Elliff and Silva, 2017; Harris et al., 2018; Reguero et al., 2018).
12 Indeed, it has been demonstrated that in small islands (such as the Cayman Islands, Grenada, Bahamas)
13 averted damages as a result of protecting intact coral reefs, can be considerable when expressed as a
14 percentage of GDP (Beck et al., 2018). Ferrario et al. (2014) conducted a global meta-analysis including
15 many small islands across the Atlantic, Pacific and Indian Oceans and found that coral reefs reduce wave
16 height by an average of 84% (and wave energy by 97%) and that reef crests alone dissipate most of this
17 energy. Based on another meta-analysis of 69 case studies worldwide (wave heights measured before and
18 after the habitat), Narayan et al. (2016) observed that coral reefs, mangroves, and seagrass reduced wave
19 height by 70%, 31% and 36%, respectively (Figure 15.4) and thus perform an essential role in protecting
20 human lives and livelihoods (high confidence). Post-TC studies have provided additional evidence for the
21 protection services offered by coastal ecosystems. On some Caribbean islands (e.g., Saint-Martin/Sint
22 Maarten) where the dense indigenous vegetation belt was preserved, the vegetative structure buffered the
23 waves of TCs Irma and José (2017), reducing the extent of marine inundation and shoreline retreat to a 30
24 m-wide coastal strip against values >160 m in deforested areas (Duvat et al., 2019a; Pillet et al., 2019). By
25 contrast, the destruction of mangrove ecosystems, even a few trees around the fringes, can accelerate coastal
26 erosion, as exemplified by observations in Micronesia (Krauss et al., 2010; Nunn et al., 2017a).
27
28 As corals, mangroves and seagrasses disappear, so do fish and other dependent organisms that directly
29 benefit industries such as ecotourism and fisheries (high confidence) (Graham et al., 2015; Cinner et al.,
30 2016). These impacts are sometimes exacerbated by catastrophic events such as tropical storms and marine
31 heatwaves that destroy habitats and hence the resources upon which coastal fisheries depend (Sainsbury et
32 al., 2018). There is high confidence that climate change impacts, together with local human disturbances,
33 will continue to denude coastal and marine ecosystem services in many small islands with serious
34 consequences for vulnerable communities (Elliff and Silva, 2017; Bindoff et al., 2019).
35
36
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1
2 Figure 15.4: Ridge-to-reef interrelated protection services delivered by ecosystems on small islands. On small islands,
3 terrestrial, coastal and marine ecosystems are interconnected and interdependent, with each ecosystem contributing
4 towards maintaining the health of the others. Together, these ecosystems provide protection services against natural
5 hazards (including flooding, erosion, landslides, mudflows, glacial melting and sedimentation) to human populations
6 living on islands. As a consequence, the degradation of one or more of these ecosystems significantly reduces the
7 protection services provided by this continuum of ecosystems. Conversely, the protection or restoration of one or more
8 of these ecosystems also provides benefits to the other ecosystems and enhances the protection services provided to
9 island inhabitants. See Box CCP1.1 for more details.
10
11
12 15.3.3.2 Impacts on Freshwater Systems
13
14 Freshwater systems on small islands are exposed to dynamic climate impacts and are considered to be
15 among the most threatened on the planet (Key Risk 3 in Box 15.1; Settele et al., 2014; IPCC, 2018; Butchart
16 et al., 2019). Hoegh-Guldberg et al. (2019) estimated that freshwater stress on small islands would be 25%
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1 less with a warming of 1.5°C or less as compared to 2.0°C. While some island regions are projected to
2 experience substantial freshwater decline, an opposite trend is observed for some western Pacific and
3 northern Indian Ocean islands (Holding et al., 2016; Karnauskas et al., 2016). Island topography and
4 ecophysiology influence water storage capacity and rainfall response potential (Dunn et al., 2018). On high
5 volcanic and granitic islands, freshwater ecosystems are often closely connected with coastal spaces, and
6 changes in freshwater supply from river systems have direct implications for salinity and sediment loads
7 (high confidence) (Yang et al., 2015; Zahid et al., 2018). Climate impacts on streamflow patterns in tropical
8 islands also create shifts in water supply for downstream users and habitat conditions for organisms
9 supporting a wide range of ecosystem services (high confidence) (Strauch et al., 2015; Frazier and
10 Brewington, 2019; Frauendorf et al., 2020).
11
12 Projected changes in aridity are expected to impose freshwater stress on many small islands, especially SIDS
13 (high confidence).These changes are congruent with drought risk projections for Caribbean SIDS (Lehner et
14 al., 2017; Taylor et al., 2018) and aligned with observations from the Shared Socio-Economic Pathway
15 (SSP) 2 scenario, where a 1°C increase in temperature (from 1.7°C to 2.7°C) could result in a 60% increase
16 in the number of people projected to experience a severe water resources stress from 20432071 (Schewe et
17 al., 2014; Karnauskas et al., 2018). In the Mediterranean region, freshwater resources will decline 1030%
18 (medium confidence) (Koutroulis et al., 2016; Kumar et al., 2020). For example, analysis of annual and
19 seasonal streamflow data on the island of Mallorca shows a decreasing trend during spring and summer, with
20 a reduction of up to 17% in some basins (Garcia, 2017).
21
22 The influence of climate change spans several variables for atoll islands with multiple, interacting forces that
23 exacerbate impacts on freshwater ecosystems (Connell, 2016), including groundwater and freshwater
24 resources (Warix et al., 2017). Analysis of groundwater resources on Roi-Namur, in the Marshall Islands,
25 reveals that the extent of salinisation of fresh groundwater lenses varies with the scale of the overwash
26 (Gingerich et al., 2017). Alsumaiei and Bailey (2018) estimated an 11-36% reduction in the fresh
27 groundwater lens volume of the small atoll islands (area < 0.6 km²) of the Maldives due to SLR. Small
28 overwash events lead to saline conditions that last for up to 3 months (Oberle et al., 2017).
29
30 SLR undermines the long-term persistence of freshwater-dependent ecosystems on islands (Goodman et al.,
31 2012) and is one of the greatest threats to the goods and services these environments provide (Box 16.1;
32 Mitsch and Hernandez, 2013). Hoegh-Guldberg et al. (2019) posit that as sea level rises, managing the risk
33 of salinisation of freshwater resources will become increasingly important. On Roi-Namur, Marshall Islands,
34 Storlazzi et al. (2018) found that the availability of freshwater is impacted by the compounding effect of
35 SLR and coastal flooding. In other Pacific atolls, Terry and Chui (2012) showed that freshwater resources
36 could be significantly affected by a 0.40 m SLR. Similar impacts are anticipated for some Caribbean
37 countries (Stennett-Brown et al., 2017). Such changes in SLR could increase salinity in estuarine and aquifer
38 water, affecting ground and surface water resources for drinking and irrigation water (Mycoo, 2018a) across
39 the region (high confidence). SLR also affects groundwater quality (Bailey et al., 2016), salinity (Gingerich
40 et al., 2017), and water-table height (Masterson et al., 2014).
41
42 15.3.3.3 Impacts on Terrestrial Biodiversity Systems
43
44 Despite encompassing approximately two percent of the Earth's terrestrial surface, oceanic and other high-
45 endemicity islands are estimated to harbour substantial proportions of existing species including ~ 25%
46 extant global flora, ~ 12% birds and ~10% mammals (Alcover et al., 1998; Wetzel et al., 2013; Kumar and
47 Tehrany, 2017). Islands also have higher densities of critically endangered species, hosting just under half of
48 all species currently considered to be at risk of extinction (Spatz et al., 2017a; Spatz et al., 2017b), hence
49 making the loss of terrestrial biodiversity and related ecosystem services a Key Risk (KR3) for small islands
50 (Figure 15.5). Impacts from developing synergies between changing climate, natural and anthropogenic
51 stressors on islands (Cross-Chapter Box DEEP in Chapter 17) could lead to disproportionate changes in
52 global biodiversity. The most prominent drivers include: SLR, increasing intensities of extreme events
53 (human activities -- especially continuing/accelerating habitat destruction/degradation) and the introduction
54 of invasive alien species (IAS) (Tershy et al., 2015). When coupled with characteristic small island traits
55 such as spatial and other resource limitations, these synergies play a critical role towards increasing the
56 vulnerability of these insular ecosystems (Box CCP1.1). This is likely to hinder the adaptation response of
57 terrestrial biota increasing the risk of biodiversity loss and in turn, impairing the resilience capacity of
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1 ecosystem functioning and services (high confidence) (Heller and Zavaleta, 2009; Ferreira et al., 2016;
2 Vogiatzakis et al., 2016).
3
4 Current observations of insular species response to climate change generally report geographic range
5 shifts/reductions for species and vegetation associations in addition to resulting impacts on local ecology
6 (Virah-Sawmy et al., 2016; Koide et al., 2017; Maharaj et al., 2019). These include changes in plant/animal
7 phenology and resulting community alterations such as for the common Mediterranean island species
8 Quercus ilex (holly oak) and Ficus carica (common fig). Species have been shifting greater distances to
9 access not only suitable climate conditions but also by association, suitable breeding conditions and seasonal
10 food. Examples include: migratory birds such as Coturnix coturnix now having earlier spring arrival dates in
11 the Mediterranean compared to six decades ago and the increased mortality of the iconic Argyroxyphium
12 sandwicense (Hinahina) as result of warmer drier trends at Hawaiian high altitudes (Krushelnycky et al.,
13 2012; Taylor and Kumar, 2016a; Vogiatzakis et al., 2016). There have also been die-offs of some species
14 from temperature extremes (e.g., flying fox species: Pteropus species) within the Pacific islands (Taylor and
15 Kumar, 2016a).
16
17 Recorded alterations of ecological interactions include increased competition, changes to migratory routes
18 (Harter et al., 2015) and mismatches between species, such as increased pathogen attacks on Mediterranean
19 forest species (Vogiatzakis et al., 2016). Also, in some areas of Madagascar there has been increased
20 vulnerability to fire, due to the replacement of succulents by less fire resilient species (Virah-Sawmy et al.,
21 2016). Further, the low functional redundancy of island ecosystems implies a comparatively higher
22 proportion of keystone species than continents, many of them being endemics (Harter et al., 2015), with
23 potentially unpredictable system consequences due to climate-induced ecological changes. For example,
24 Caribbean land crabs have been observed to alter their food intake as a response to drying conditions
25 (McGaw et al., 2019) and Aldabra giant land tortoises have reduced their activity in response to increasing
26 temperature and decreasing precipitation (Falcon and Hansen, 2018); such changes in both these ecosystem
27 engineers are of potential consequence for seed dispersal, among other ecological functions.
28
29 The majority of studies modelling geographical range changes of small island species, to even the most
30 optimistic 21st century climate change scenarios imply a reduction in climate refugia (Table 15.3, Box
31 CCP1.1). This is due to projected strong shifts, reductions or even complete losses of climatic niches
32 resulting from inadequate geographic space for species to track suitable climate envelopes (high confidence)
33 (e.g., Maharaj and New, 2013; Fortini et al., 2015; Struebig et al., 2015b). Because of the high proportion of
34 global endemics hosted within small and especially isolated islands, the resulting increased extinction risk of
35 such species (up to 100%) could lead to disproportionate losses in global biodiversity (medium to high
36 confidence) (Harter et al., 2015; Manes et al., 2021).
37
38 SLR has been projected to impact the terrestrial biodiversity of low-lying islands and coastal regions via
39 large habitat losses both directly (e.g., submergence) and indirectly (e.g., salinity intrusion, salinisation of
40 coastal wetlands and soil erosion) at even the 1m scenario (medium to high confidence). However, these
41 impacts vary depending on the islands' topographical differences. In a study of SLR impacts on insular
42 biodiversity hotspots, (Bellard et al., 2013a) reported that the Caribbean islands, Sundaland and the
43 Philippines were projected to suffer the most habitat loss while the East Melanesian islands were projected to
44 be lesser (but not minimally) affected. The most threatened of these, the Caribbean, was projected to have
45 between 8.7% to 49.2% of its islands entirely submerged respectively from 1m to 6 m SLR (Bellard et al.,
46 2013a). However, many current projection studies consider marine flooding directly and seldom incorporate
47 other indirect impacts such as increased habitat losses from horizontal erosion loss, increased salinity levels,
48 tidal ranges and extreme events. These projections are considered to be conservative, underestimating the
49 extent of habitat loss to terrestrial biodiversity (Bellard et al., 2013b).
50
51 Marine flooding is expected to destroy habitats of coastal species, particularly range-restricted coastal and/or
52 single-island endemics (many already listed as at least `threatened' by the International Union for
53 Conservation of Nature [IUCN]) within the limited terrain on atoll islands. These species have limited
54 opportunities to accommodate such direct impacts of climate change apart from shifting further inland or to
55 other neighbouring atolls which might have favourable habitat. However, fragmentation of habitat due to
56 anthropogenic activity may hinder migration further inland, while shifting to neighbouring islands is not
57 viable due to the water barrier between islands (high confidence) (Bellard et al., 2013b; Wetzel et al., 2013;
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1 Kumar and Tehrany, 2017). Additionally, migratory birds, which use small islands (e.g. atolls) for stopovers
2 or breeding/nesting sites, are projected to become impacted. Within the Mediterranean and Caribbean,
3 significant losses to coastal wetlands - critical habitat for migratory birds has already been observed, with
4 further significant habitat losses, redistribution and changes in quality being projected across island systems
5 such as the Bahamas (Caribbean) and Sardinia (Mediterranean) (Vogiatzakis et al., 2016; Wolcott et al.,
6 2018).
7
8 Indirect impacts of SLR may potentially result in equal or more biodiversity loss than direct impacts
9 (medium confidence). Relocation of displaced coastal human populations and associated intensive
10 agriculture and urban areas inland to natural habitat may result in greater biodiversity loss than direct
11 impacts especially on islands with large coastal populations and urban centres (Wetzel et al., 2012; Bellard
12 et al., 2013b). Given the dense population of insular hotspots (~31.8% of existing humans within ~ 15.9% of
13 inhabited global land area) and the fact that on many islands, large proportions of human populations live
14 within coastal regions, it has been suggested that immense impacts from such relocations should be factored
15 into projection and adaptation studies (Wetzel et al., 2012).
16
17 Tropical island natural habitats/systems are highly vulnerable to extreme weather events such as TCs, due to
18 their small size, unique ecological systems and often low socio-economic capacity (high confidence) (Box
19 15.2; Goulding et al., 2016; Schütte et al., 2018). Growing evidence suggests high resilience of forest
20 habitats (Keppel et al., 2014; Luke et al., 2017), especially within intact forest ecosystems to hurricanes and
21 cyclones (Goulding et al., 2016). While initial damage can be high, relatively fast recovery rates have been
22 reported for both floral and faunal components of these ecosystems (Cantrell et al., 2014; Shiels et al., 2014;
23 Monoy et al., 2016; Richardson et al., 2018). Within the Caribbean in particular, high resilience of forest
24 types has been associated with the current intensity and return rate of hurricanes over the last 150 years.
25
26 It should however be underscored that these relatively fast recovery rates are associated with the present
27 intensity and return rate of TCs. They do not reflect the impacts of increasingly intense events such as
28 Hurricane Dorian (2019), which resulted in almost complete inundation of several low-lying islands of the
29 Bahamas from storm surges. Severe weather events also have indirect effects on islands' biodiversity --
30 interacting synergistically with other stressors, such as increased invasion by non-native species and land use
31 change. For example, TCs within Papua New Guinea resulted in the destruction of subsistence gardens,
32 which led inhabitants to clear forest areas for new farming areas and for harvesting of timber resources to
33 rebuild (Goulding et al., 2016).
34
35 The most recent projections suggest that TC intensity is predicted to increase as climate continues to change
36 (Walsh et al., 2016; Kossin et al., 2017). There are too few studies available to suggest potential future
37 response trends of these ecosystems to this increased intensity, however it seems plausible that present
38 resilience capacities may be adversely impacted (medium confidence) (Marler, 2014). Further, the potential
39 for stressors such as forest fragmentation/degradation or IAS combining with these increasingly intense
40 events to cause precipitating ecosystem cascades is a real concern (Goulding et al., 2016).
41 Continued high rates of habitat loss and degradation have been reported for many small islands as natural
42 habitats continue to be cleared to meet increasing demands upon natural resources from rising human
43 populations, agriculture, urbanisation, unsustainable tourism, overgrazing and fires. This increases the
44 vulnerability of ecosystems within especially oceanic islands -- where isolation has given rise to high levels
45 of endemism but simple biotic communities, with low functional redundancy (Box CCP1.1). There is high
46 confidence that climate change may exacerbate the effects of this habitat loss upon the biodiversity of these
47 islands as the climate refugia (Table 15.3) and the upslope shifts of range-restricted, dispersal-limited and
48 poorly competitive species, confined within narrow latitudinal (and decreasing altitudinal) gradients, are
49 increasingly challenged by fragmented and degraded landscapes (e.g., Struebig et al., 2015a; IPBES, 2019).
50 Additionally, high-altitude ecosystems such as cloud forests which harbour high levels of endemism are
51 projected to shrink due to increasing atmospheric temperature and competition from upward-shifting
52 lowland species (Taylor and Kumar, 2016a). These may ultimately increase the risk of multiple extinctions,
53 negatively impacting upon global biodiversity levels (high confidence) (Taylor and Kumar, 2016a; Portner et
54 al., 2021).
55
56 Analyses of historical and current threats indicate that IAS and disease have been the primary drivers of
57 insular extinctions in modern history (Bellard et al., 2016). Impacts of IAS on islands are projected to
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1 increase with time due to synergies between climate change and other traditional drivers such as increasing
2 global trade, tourism, agricultural intensification, over exploitation and urbanisation (Bellard et al., 2014;
3 Russell et al., 2017). Changing climate conditions may not necessarily increase the rate of IAS introductions
4 but is expected to improve chances of IAS establishment via (i) altering IAS transport and introduction
5 mechanisms, (ii) increasing the impacts and distributions of existing IAS and (iii) altering the effectiveness
6 of existing control strategies (Hellmann et al., 2008; Russell et al., 2017). These are likely to enhance IAS
7 impacts on islands including: restructuring of ecological communities leading to declines and
8 extinctions/extirpations in flora and fauna, habitat degradation, declining ecosystem functioning, services
9 and resilience, and in extreme cases, potential community homogenisation (high confidence) (Russell and
10 Blackburn, 2017; IPBES, 2019). Given the high degree of endemicity within oceanic islands and their
11 associated vulnerabilities, such exacerbation by changing climate pose a serious threat to decreasing global
12 biodiversity (medium to high confidence) (van Kleunen et al., 2015).
13
14 Compared to continents, terrestrial IAS are disproportionately prevalent on islands (almost three-quarters of
15 global species currently threatened by IAS and disease are found on islands) and also generate stronger
16 impacts (e.g., within alpine ecosystems of high islands) than on continents (high confidence)(Bellard et al.,
17 2014; Bellard et al., 2016; Frazier and Brewington, 2019). Russell and Blackburn (2017) suggested a
18 correlation between small island size and increased numbers of IAS. SIDS within the Indian Ocean and in
19 particular, the Pacific SIDS region were reported to have significantly more IAS (medium confidence), while
20 the Caribbean and Atlantic SIDS have fewer numbers but faster accumulation of IAS. Finally, while there
21 have been developments in the eradication of IAS on islands (Jones et al., 2016), there is sparse evidence and
22 hence assessment of the degree to which measures designed to prevent introduction and to manage invasion
23 pathways and establishment have been successful.
24
25
26 Table 15.3: Percentage of selected islands classified as refugia for biodiversity at increasing levels of warming. While
27 protected land is still `protected' this table demonstrates the difficulty of protecting lands which might be `more
28 resilient' to climate change under increasing levels of warming and current land use practices. Derived from current and
29 future projected distributions of ~130,000 terrestrial fungi, plants, invertebrates and vertebrates (Warren et al., 2018a).
30 Refugia =areas remaining climatically suitable for >75% of the species modelled (Warren et al., 2018b). Projections:
31 based on mean impacts from 21 CMIP5 climate model patterns (no dispersal) and elevationally downscaled to 1km
32 under interpolated warming levels derived from RCP 2.6, 4.5, 6.0 and 8.0 (Warren et al., 2018a). First column-set = %
33 island/island chain classified as a refugia based on climate alone ; second column-set = % natural land projected to be
34 climate refugia -- illustrating potential refugia `space' already lost to habitat conversion. Colour Key: white > 50%;
35 yellow = 30%-50%; red = 17%-30% and dark red <17% of land classified as refugia.
36 [INSERT TABLE 15.3 HERE]
37
38
39 15.3.4 Observed Impacts and Projected Risks on Human Systems
40
41 15.3.4.1 Island Settlements and Infrastructure
42
43 As a result of slow onset ocean and climate changes and changes in extreme events, settlements and
44 infrastructure of small islands are at growing risk due to climate change in the absence of adaptation
45 measures (high confidence). Ocean acidification and deoxygenation, increased ocean temperatures and
46 relative sea level rise are impacting marine, coastal and terrestrial biodiversity and ecosystem services,
47 making settlements more exposed and vulnerable to climate-related hazards. Changes in rainfall patterns
48 such as heavy precipitation result in annual flood events that damage major assets and result in a loss of
49 human life. Examples of settlements where this has occurred are Port of Spain (Mycoo, 2014b; Mycoo,
50 2018a) , Haiti (Weissenberger, 2018), Viti Levu (Brown et al., 2017; Singh-Peterson and Iranacolaivalu,
51 2018), urban areas of Fiji and Kiribati (McAneney et al., 2017; Cauchi et al., 2021), Male', Maldives
52 (Wadey et al., 2017), and Mahé, in the Seychelles (Etongo, 2019).
53
54 The main settlements of small islands are located along the coast and with decades of high density coastal
55 urban development, their population, buildings and infrastructure are currently exposed to multiple climate
56 change-related hazards (Kumar and Taylor, 2015; Mycoo, 2017) and face key risks (high confidence) (KR5
57 in Figure 15.5). In many small islands, population is concentrated in the Low Elevation Coastal Zone
58 (LECZ) which is defined as coastal areas below 10 metres elevation. Approximately 22 million in the
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1 Caribbean live below 6 metres elevation (Cashman and Nagdee, 2017) and an estimated 90% of Pacific
2 Islanders live within 5 km of the coast, if Papua New Guinea is excluded (Andrew et al., 2019). In the
3 Solomon Islands and Vanuatu, over 60% of the population lives within 1 km of the coast (Andrew et al.,
4 2019). Most Pacific islands have 50% of their infrastructure within 500 metres of the coast (Kumar and
5 Taylor, 2015), and in Kiribati, Marshall Islands and Tuvalu, >95% of the infrastructure is located in the
6 LECZ (Andrew et al., 2019) (Figure 15.3). Sustainable development challenges including insufficient land
7 use planning and land use competition contribute to increased vulnerability of human settlements to climate
8 change in small islands (Kelman, 2014)(Mycoo, 2021).
9
10 Categories 4 and 5 TCs are severely impacting settlements and infrastructure in small islands. TC Maria in
11 2017 destroyed nearly all of Dominica's infrastructure and losses per unit of GDP amounted to more than
12 225% of the annual GDP (Eckstein et al., 2018). Destruction from TC Winston in 2016 amounted to more
13 than 20% of Fiji's current GDP (Cox et al., 2018). Additionally, living conditions in human settlements are
14 changing due to storm surge which is already penetrating further inland compared with a few decades ago
15 (IPCC, 2018 Section 3.4.4.3; Brown et al., 2018).
16
17 A growing percentage of the population in small islands lives in informal settlements which occupy marginal
18 lands leading to increased population exposure and vulnerability to climate-related hazards (Mycoo and
19 Donovan, 2017). Unplanned settlements have compounded flooding brought on by slow onset hazards such
20 as coastal and riverine flooding and fast onset events such as TCs and storm surges (Butcher-Gollach, 2015;
21 Chandra and Gaganis, 2016; Mycoo, 2017). Unsustainable land use practices and difficulties in enforcing
22 land use zoning and building guidelines in informal settlements make them highly vulnerable to such events
23 (Butcher-Gollach, 2015; Mecartney and Connell, 2017; Mycoo, 2017; Mycoo, 2018b; Trundle et al., 2018;
24 Mycoo, 2021).
25
26 TC intensification in the future is likely to cause severe damage to human settlements and infrastructure in
27 small islands. Additionally, SLR is expected to cause significant loss and damage (Martyr-Koller et al.,
28 2021). Based on SLR projections, almost all port and harbour facilities in the Caribbean will suffer
29 inundation in the future (Cashman and Nagdee, 2017). In Jamaica and St Lucia, SLR and ESLs are projected
30 to be key risks to transport infrastructure at 1.5°C unless further adaptation is undertaken (Monioudi et al.,
31 2018). Similar findings were reported for Samoa (Fakhruddin et al., 2015). Even islands of higher elevation
32 are expected to be threatened, given the high amount of infrastructure located near to the coast, for example
33 Fiji (Kumar and Taylor, 2015).
34
35 15.3.4.2 Human Health and Well-being
36
37 Small islands face disproportionate health risks associated with changes in temperature and precipitation,
38 climate variability, and extremes (Cross-Chapter Box INTERREG in Chapter 16; Key Risk 4 in Section
39 15.3.9, Figure 15.5). Climate change is projected to increase the current burden of climate-related health
40 risks (Weatherdon et al., 2016; Ebi et al., 2018; Schnitter et al., 2019). Health risks can arise from exposures
41 to extreme weather and climate events, including heatwaves; changes in ecological systems associated with
42 changing weather patterns that can result, for example, in more disease vectors, or in compromised safety
43 and security of water and food; and exposures related to disruption of health systems, migration, and other
44 factors (see Cross-Chapter Box ILLNESS in Chapter 2; McIver et al., 2016; Mycoo, 2018a; WHO, 2018).
45
46 Extreme weather and climate events, particularly TCs, floods, drought, and heat waves can cause injuries,
47 infectious diseases, and deaths (Box 15.1; Schütte et al., 2018). For example, category 5 TC Winston hit Fiji
48 on 20 February 2016. During the national state of emergency (7 March and 29 May 2016), the World Health
49 Organization portable toolkit for an early warning alert and response system (EWARS in a Box) was
50 deployed within 24 hours; it recorded 34,113 cases of the nine syndromes among 326,861 consultations in a
51 population of about 900,000; 48% of cases were influenza-like illnesses, 30% were acute watery diarrhoea,
52 and 13% were suspected cases of dengue. There also were 583 cases of Zika-like illness (1.7% of all cases)
53 and two large outbreaks of viral conjunctivitis (total of 880 cases). During TC Maria in Puerto Rico, there
54 were more deaths per 100,000 among individuals living in municipalities with the lowest socioeconomic
55 development and for men 65 years of age or older (Santos-Burgoa et al., 2018); this excess risk persisted for
56 at least a year after the event. The first human cases of leptospirosis in the U.S. Virgin Islands occurred in
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1 2017 after TC Irma and Maria. TCs also can affect treatment and care for people with non-communicable
2 diseases, including exacerbation or complications of illness and premature death (Ryan et al., 2015).
3
4 Heat-related mortality and risks of occupational heat stress in small island states are projected to increase
5 with higher temperatures (Hoegh-Guldberg et al., 2018; Mendez-Lazaro et al., 2018). Higher temperatures
6 also can affect the productivity of outdoor workers (Taylor et al., 2021). Climate change, urbanization, and
7 air pollution are risk factors for the rise of allergic diseases in Asia and the (Pawankar et al., 2020).
8
9 Tropical and sub-tropical islands face risks from vector-borne diseases, such as malaria, dengue fever, and
10 the Zika virus. El Niño events can increase the risk of diseases such as Zika virus by increasing biting rates,
11 decreasing mosquito mortality rates, and shortening the time required for the virus to replicate within the
12 mosquito (Caminade et al., 2017). By combining disease prediction models with climate indicators that are
13 routinely monitored, alongside evaluation tools it is possible to generate probabilistic dengue outlooks in the
14 Caribbean and early warning systems (Oritz et al., 2015; Lowe et al., 2018). Projections suggest that more
15 individuals will become at risk of dengue fever by the 2030s and beyond because of an increasing abundance
16 of mosquitos and larger geographic range (Ebi et al., 2018). Projected increases in mean temperature could
17 double the dengue burden in New Caledonia by 2100 (Teurlai et al., 2015). In the Caribbean, Saharan dust
18 transported across the Atlantic can interact with Caribbean seasonal climatic conditions to become respirable
19 and contribute to asthma presentations at the emergency department (See Table 15.5; Akpinar-Elci et al.,
20 2015).
21
22 Ciguatera fish poisoning (CFP) is a foodborne illness caused by toxic dinoflagellate algae that proliferate on
23 degraded coral reefs and that can contaminate reef fish; symptoms can remain for a few weeks to months.
24 CFP occurs in tropical and subtropical regions, primarily in the South Pacific and Caribbean, but wherever
25 reef fish are consumed (Traylor and Singhal, 2020). In the Caribbean Sea, increasing ocean temperatures are
26 expected to stabilize or slightly decrease the incidence of CFP because of shifts in species distribution of
27 dinoflagellates associated with CFP (Kibler et al., 2015). CFP is endemic in the Cook Islands and French
28 Polynesia, where incidence is associated with sea surface temperature anomalies (Zheng et al., 2020). In the
29 Canary Islands, tropicalization trends due to climate change are expected to increase CFP occurrence in the
30 future (Rodriguez et al., 2017). In addition, in the Caribbean, increased density of Sargassum algae, possibly
31 due to ocean temperature impacts on ocean currents compounded by agricultural pollution, may lead to
32 increased respiratory illnesses (Resiere et al., 2018; Resiere et al., 2019; Resiere et al., 2020).
33
34 Climate driven changes in the ability to access locally grown or harvested food, either through
35 environmental degradation or changes in extreme event magnitude and/or frequency, can increase
36 dependence on imported food and increase rates of malnutrition and non-communicable diseases
37 (Springmann et al., 2016; WHO, 2018; Savage et al., 2019; Lieber et al., 2020). Projections suggest that
38 local food accessibility could be reduced by 3.2% in the low- and middle-income countries of the Western
39 Pacific (including the Philippines, Fiji, Papua New Guinea, Solomon Islands, and other Pacific islands) by
40 2050, with approximately 300,000 associated deaths possible (Springmann et al., 2016). A climate change-
41 related 20% decline in coral reef fish production in some Pacific Island countries by 2050 could exacerbate
42 the population growth-driven gap between volume of fish needed for nutritional security and fish available
43 through sustained harvest (Bell et al., 2013; Cauchi et al., 2019; Savage et al., 2019)).
44
45 Heavy reliance on aquifers and rainwater harvesting in small islands, particularly atolls, coupled with
46 overcrowding, population growth, and contamination increase the risk of waterborne disease (McIver et al.,
47 2014; Strauch et al., 2014; McIver et al., 2016). For example, seasonal rainfall in Kiribati is associated with
48 waterborne disease (such as diarrhea, cholera, and typhoid fever). Future projections indicate increases in the
49 number of days of heavy rainfall by 2050, suggesting future increases in risk in heavily populated areas
50 (McIver et al., 2014). Damage to water and sanitation services can cause infectious disease outbreaks, such
51 as the cholera outbreak that occurred in Haiti following TC Matthew (Raila and Anderson, 2017; Hulland et
52 al., 2019).
53
54 Evidence is emerging of the mental health impacts of climate change. Tuvaluans are experiencing distress
55 because of the local environmental impacts caused or exacerbated by climate change, and by hearing about
56 the potential future consequences of climate change (Gibson et al., 2020).
57
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1 15.3.4.3 Water Security
2
3 Climate change impacts on freshwater systems frequently exacerbate existing pressure, especially in
4 locations already experiencing water scarcity (Section 15.3.3.2 and Cross-Chapter Box INTERREG in
5 Chapter 16; Schewe et al., 2014; Holding et al., 2016; Karnauskas et al., 2016), making Water Security a
6 Key Risk (KR4 in Figure 15.5) in small islands. Small islands are usually environments where demand for
7 resources related to socio-economic factors such as population growth, urbanisation and tourism already
8 place increasing pressure on limited freshwater resources. In many small islands, water demand already
9 exceeds supply. For example, in the Caribbean, Barbados is utilising close to 100% of its available water
10 resources and St. Lucia has a water supply deficit of approximately 35% (Cashman, 2014). On many
11 Mediterranean islands, water demand regularly outstrips supply as a result of low average precipitation
12 coupled with increasing water demand from economic activities such as irrigated agriculture and tourism
13 (Hof et al., 2014; Papadimitriou et al., 2019).
14
15 Population growth plays a strong role in projected future water stress (Schewe et al., 2014). Combining
16 projected aridity change (fractional change compared to historical climatology) with population projections
17 derived from SSP2, shows that the SIDS with high projected population growth rates are expected to
18 experience the most severe freshwater stress by 2030 under a 2°C warming threshold scenario (Karnauskas
19 et al., 2018). For several SIDS (e.g., Belize and Jamaica), increasing aridity change is a prominent
20 exacerbating factor, but for others (e.g., the Solomon Islands and Comoros) population growth is the main
21 factor. A 1°C increase in temperature (from 1.7°C to 2.7°C) could result in a 60% increase in the number of
22 people projected to experience a severe water resources stress in 20432071 (Schewe et al., 2014;
23 Karnauskas et al., 2018). Research on Jamaica concluded that the ability of rainwater harvesting to meet
24 potable water needs between the 2030s and 2050s will be reduced based on predicted shorter intense
25 showers and frequent dry spells (Aladenola et al., 2016).
26
27
28 The Caribbean and Pacific regions have historically been affected by severe droughts (Peters, 2015; FAO,
29 2016; Barkey and Bailey, 2017; Paeniu et al., 2017; Trotman et al., 2017; Anshuka et al., 2018) with
30 significant physical impacts and negative socio-economic outcomes. Water quality is affected by drought as
31 well as water availability. The El Niño related 2015-16 drought in Vanuatu led to reliance on small amounts
32 of contaminated water left at the bottom of household tanks (Iese et al., 2021). The highest land disturbance
33 percentages have coincided with major droughts in Cuba (de Beurs et al., 2019). Drought has been shown to
34 have an impact on rainwater harvesting in the Pacific (Quigley et al., 2016) and Caribbean (Aladenola et al.,
35 2016), especially in rural areas where connections to centralised public water supply have been difficult.
36 Increasing trends in drought are apparent in the Caribbean (Herrera and Ault, 2017) although trends in the
37 western Pacific are not statistically significant (McGree et al., 2016).
38
39 Areas where a freshwater lens is thinner are most likely to be impacted by multiple climate stressors, and
40 these areas tend to be in coastal zones where populations are likely to be most concentrated (Holding et al.,
41 2016). In Barbados, where groundwater is relied upon for food production, urban use, and environmental
42 needs, higher food prices are expected in the future if informed land use management and integrated water
43 resources policy implementation are not implemented to manage groundwater in the short term, even with
44 modest climate change threats (Gohar et al., 2019).
45
46 15.3.4.4 Fisheries and Agriculture
47
48 Fisheries provide small islands with opportunities for economic development, revenues, food security and
49 livelihoods (Bell et al., 2018). Ten Pacific Island countries and territories derive between 5% and >90% of
50 all government revenue (except grants) from access fees paid by industrial tuna-fishing fleets, mainly from
51 distant-water fishing nations (Bell et al., 2018; SPC, 2019). Under a high greenhouse gas emissions scenario
52 (RCP 8.5), the total biomass of three tuna species in the waters of ten Pacific SIDS could decline by an
53 average of 13% (range = -5% to -20%) due to a greater proportion of fish occurring in the high seas (Bell et
54 al., 2021), meanwhile projected increases have been anticipated for Ascension Island and Saint Helena in the
55 South Atlantic (Townhill et al., 2021). Additionally, seafood plays an important role in achieving food
56 security in many islands. In the Pacific, fish protein is estimated to make up 50-90% of animal protein
57 consumption in rural areas, and 40-80% in urban areas (Bell et al., 2009; Hanich et al., 2018) with similar
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1 values reported for some Indian Ocean and Caribbean islands (e.g. Maldives, Antigua and Barbuda). It has
2 been suggested that island nations may need to retain more of their tuna catch rather than relying solely on
3 coastal fisheries to achieve food security in the future (Cross-Chapter Box MOVING PLATE in Chapter 5;
4 Bell et al., 2015; Bell et al., 2018). Furthermore, small island fisheries can be severely impacted by extreme
5 events such as TCs, yet rapidly recovering pelagic fisheries can help to alleviate immediate food insecurity
6 pressures in some circumstances, helping to build resilience (Pinnegar et al., 2019).
7
8 Observed impacts of climate change on fish and fisheries in small islands include declines in reef-associated
9 species due to coral bleaching or cyclone damage (Robinson et al., 2019; Magel et al., 2020), oceanic-scale
10 shifts in the distribution of large pelagic fish and hence their fisheries (Erauskin-Extramiana et al., 2019),
11 changes to the size structure or breeding behaviour of species (e.g. (Asch et al., 2018)(Sections 3.3.3.2 and
12 3.4.3.1)). Many studies of future fisheries productivity in a changing climate suggest that yields will fall as a
13 result of ocean productivity reductions, local species extinction and/or migration (Nurse, 2011; Asch et al.,
14 2018; Robinson et al., 2019). Asch et al. (2018) provided future projections for biodiversity and fisheries
15 maximum catch potential in Pacific Island countries and territories. These authors concluded that 9 of 17
16 Pacific Island entities (Cook Islands, Federated States of Micronesia, Guam, Kiribati, Marshall Islands, Niue,
17 Papua New Guinea, Solomon Islands, and Tuvalu) could experience 50% declines in maximum catch
18 potential by 2100 relative to 19802000 under both an RCP 2.6 and RCP 8.5 scenario (medium confidence).
19 In Wallis and Futuna, maximum catch potential was projected to increase slightly (around 10%) by 2050,
20 later declining by the year 2100. Similar projections have now been provided for all countries worldwide,
21 including Pacific, Caribbean, Atlantic, Mediterranean and Indian Ocean small islands (Cheung et al., 2018).
22 The small islands that show the largest anticipated decrease in fisheries maximum catch potential by the end
23 of the century (according to an RCP4.5 and RCP 8.5 scenario) included the Federated States of Micronesia,
24 Kiribati, Nauru, Palau, Tokelau, Tuvalu, São Tomé and Príncipe, whereas some other small islands such as
25 Bermuda, Easter Island (Chile), and Pitcairn Islands (UK), might actually witness increases in fish catch
26 potential (medium confidence) (Cheung et al., 2018). Monnereau et al. (2017)showed that for the fisheries
27 sector, small island states are generally more vulnerable to climate change impacts compared to continental
28 least developed countries or coastal states because of their increased reliance on fisheries, the exposure of
29 coastal communities to potential climatic threats and their limited adaptive capacity.
30
31 Projected impacts of climate change on agriculture and fisheries pose serious threats to dependent human
32 populations (Ren et al., 2018; Hoegh-Guldberg et al., 2019), making the risk caused to livelihoods a Key
33 Risk in small islands (KR7 in Figure 15.5). On small islands, despite biophysical commonalities (e.g., size
34 and isolation), differences in economic status and level of dependence on agriculture and fisheries produce
35 dynamic climate impacts (Balzan et al., 2018). Climate change is impacting agricultural production in small
36 islands through slow-onset stressors such as rising average temperatures, shifting rainfall patterns, sea level
37 rise and extreme events like TCs. For example, TC Pam, a Category 5 cyclone, devastated Vanuatu in 2015
38 and caused losses and damages to the agriculture sector valued at USD 56.5 million (64.1% of GDP) (Nalau
39 et al., 2017) and TC Winston Winston in 2016 resulted losses and damages on the agriculture sector in Fiji
40 valued at USD 254.7 million (Iese et al., 2020). In 2017, total loss and damage associated with hurricane
41 Maria (category 5) amounted to 224% of Dominica's 2016 GDP (Barclay et al., 2019). Losses and damage in
42 agriculture often led to people eating imported processed foods affecting their diet and nutrition (Haynes et
43 al., 2020).Small Islands' communities are also witnessing the indirect effects of the covid-19 pandemic on
44 agricultural systems (Hickey and Unwin, 2020). However, the limited diversity of agriculture production and
45 reduced household incomes are contributing to low diet diversity (Iese et al., 2020). Bell and Taylor (2015)
46 assessed the effects of climate change on specific sectors of agriculture in the Pacific islands region and
47 found that, by 2090, staple food crops of taro, sweet potato, and rice are expected to suffer from moderate to
48 high impact. Among export crops, coffee is expected to sustain the most significant impact due largely to
49 increased temperatures in the highland areas of Papua New Guinea a high production area (Bell et al.,
50 2016). Livestock is an important protein source in some small islands and is particularly vulnerable to
51 changes in temperature through heat stress (Bell and Taylor, 2015; Lallo et al., 2018). With the concentration
52 of island people along (often reef-fringed) coasts, there is a comparatively large dependence on nearshore
53 marine foods and coastal agricultural systems (Ticktin et al., 2018).
54
55 In the Caribbean, additional warming by 0.2°1.0°C, could lead to a predominantly drier region (5%15%
56 less rain than present-day), a greater occurrence of droughts (Taylor et al., 2018) along with associated
57 impacts on agricultural production and yield in the region (Gamble et al., 2017; Hoegh-Guldberg et al.,
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1 2019; Nicolas et al., 2020). Crop suitability modeling on several commercially important crops grown in
2 Jamaica found that even an increase less than +1.5 °C could result in a reduction in the range of crops that
3 farmers may grow (Rhiney et al., 2018).
4
5 Sugar yield in Fiji could decline by 214% under projected scenarios (McGree et al., 2020). Farmers in some
6 small islands have utilised Indigenous knowledge systems built on local ontology to sharpen their sensitivity
7 to environmental conditions (Shah et al., 2018). However, projected climate change across the Pacific could
8 undermine climate-sensitive agricultural livelihoods and exacerbate food insecurity challenges (McCubbin et
9 al., 2017; Campbell et al., 2021).
10
11 Projected climate impacts on island agroecosystem services could accentuate a myriad of social and
12 ecological risks (Campbell, 2021). Without proactive farm management practices, the projected impacts of
13 climate change on drought patterns is a major threat to cocoa pollination services (Arnold et al., 2018). Many
14 tropical island agroforestry crops are completely dependent on insect pollination and it is therefore important
15 to understand the climatic drivers of changing conditions related to pollinator abundance. Coastal
16 agroforestry systems in small Pacific islands are vital to national food security but native biodiversity is
17 rapidly declining (Ticktin et al., 2018). Biodiversity loss from traditional agroecosystems is a major threat to
18 food and livelihoods security in SIDS (UNEP, 2014a). Additionally, while coastal-lowland salinisation and
19 more-frequent flooding attributable to SLR have impacted coastal agriculture on some islands (Cruz and
20 Andrade, 2017; Wairiu, 2017), stronger TCs can sometimes shock island terrestrial food production
21 warranting reconfiguration (Mertz et al., 2010; Duvat et al., 2016; Chakrabarti et al., 2017). Calls to conserve
22 associated environments and to make terrestrial food production on islands more resilient to climate-driven
23 shocks underscore concern about future food security (Connell, 2013; de Scally, 2014). Implicit in the latter
24 is reversing the decades-long loss of Indigenous knowledge about food production in many island societies
25 and incorporating it into future strategies (Mercer et al., 2014b; Janif et al., 2016).
26
27 15.3.4.5 Economies
28
29 Small-island economies vary greatly in their nature, history/trends, and viability under a changed climate. As
30 elsewhere, few small island economies are overseen by governments that are adequately prepared for the
31 economic impacts of climate change over the next few decades (Connell, 2013; Hay, 2013). In particular, the
32 lack of diversity that characterizes most small-island economies means they are especially vulnerable to
33 global (climate-driven) shocks (Cross-Chapter Box DEEP in Chapter 17), be these the impacts of extreme
34 events or more gradual longer-term change, which makes the maintenance of traditional mechanisms for
35 coping with such shocks in many island societies all the more important (Granderson, 2017; Wilson and
36 Forsyth, 2018; Nunn and Kumar, 2019b). As a result, the risk from climate change to economies constitutes
37 a Key Risk (KR7 in Figure 15.5) in small islands.
38
39 Many island environments have been commercially exploited by external interests for much of their recent
40 history. This is especially common for timber, the wholesale removal of forests, especially on tropical
41 islands, exposing land to heavy rain that leads to denudation and increases lowland sedimentation (Wairiu,
42 2017; Eppinga and Pucko, 2018). Negative aspects of both processes will be exacerbated by climate change,
43 demonstrating the practical need for reforestation in many island contexts (Thomson et al., 2016).Some
44 small-island economies are sustained by extractive industries such as mining, creating dependencies that lead
45 to their environmental impacts being downplayed (Tserkezis and Tsakanikas, 2016; Shepherd et al., 2018). It
46 is important to address these impacts as they will add to negative impacts of climate change (Clifford et al.,
47 2019).
48
49 Many small-island economies are sustained by tourism and have invested heavily in associated infrastructure
50 and capacity building (Cannonier and Burke, 2018). Some rural island communities have become dependent
51 on tourism to the point that it would be difficult to revert to subsistence living (Lasso and Dahles, 2018).
52 Coast-focused (beach-sea) tourism in island contexts is already being impacted by beach erosion, elevated
53 high SST causing coral bleaching, and associated marine-biodiversity loss, as well as more intense TCs
54 (Tapsuwan and Rongrongmuang, 2015; Parsons et al., 2018; Wabnitz et al., 2018). The Covid-19 pandemic
55 travel disruption significantly affected Caribbean islands tourism sector by reducing incomes that would
56 have been used to enhance climate resilience (Sheller, 2020). Many tourism interests downplay the impacts
57 and future risks from climate change (Shakeela and Becken, 2015), a position that may be borne out by
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1 sustained/rising demand for small island vacationing in some locales (Katircioglu et al., 2019). A way
2 forward is for island tourism to emphasize its low-carbon and sustainable attributes, and to encourage
3 smaller-scale eco-friendly holiday opportunities (Lee et al., 2018), in other words for island nations to
4 embrace a `blue economy' in line with SDG14 to conserve and utilise their oceans for sustainable futures
5 (Hampton and Jeyacheya, 2020; Hassanali, 2020).
6
7 Given the high cost of imported goods, especially foodstuffs, larger island jurisdictions are striving to
8 transform their economies to favour locally produced or locally constituted materials that employ local
9 people and reduce their cost of living. The exposure of this component of island economies varies, yet
10 manufacturing/commercial operations are usually found in the lowest-lying areas, often on reclaimed lands.
11 This makes them especially vulnerable to rising sea level, part of a larger issue around the disproportionate
12 exposure of infrastructure on small islands to climate change (Fakhruddin et al., 2015; Kumar and Taylor,
13 2015).
14
15 It is challenging to disentangle the role of climate change from that of globalisation and development in
16 recent changes to human livelihoods on small islands, given that the latter have characterised many
17 especially SIDS within the last few decades. However, recent climate change is clearly implicated in
18 livelihood deterioration in many island contexts (Hernandez-Delgado, 2015; Nunn and Kumar, 2018). For
19 example, livelihood impacts of climate-driven stressors (including shoreline/riverbank erosion, flooding and
20 erratic rainfall) in three Mahishkhocha island-chars (river-mouth sand islands of Bangladesh) have been
21 amplified by inadequate/misguided policy (Saha, 2017).The subordination of IKLK in favour of external
22 adaptation strategies has accelerated livelihood decline in many island contexts (Wilson and Forsyth, 2018).
23 Although economic and financial development has the potential to reduce environmental (and livelihood)
24 degradation in SIDS (Seetanah et al., 2019), it is also clear that uneven development can steepen core-
25 periphery disparities, especially in archipelagic contexts, resulting in deteriorating rural/peripheral
26 livelihoods at the expense of improving urban ones (Wilson, 2013; Sofer, 2015) and increased rural-urban
27 migration (Birk and Rasmussen, 2014; Connell, 2015).
28
29 15.3.4.6 Migration
30
31 Climate-related migration is considered to be a particular issue for small islands because changes in extreme
32 events and slow-onset changes affect increasingly highly exposed and vulnerable low-lying coastal
33 populations, therefore causing a threat to small island habitability (KR9 in Figure 15.5) (Storey and Hunter,
34 2010; Kumar and Taylor, 2015; Duvat et al., 2017b; Weir and Pittock, 2017; Hoegh-Guldberg et al., 2018;
35 Mycoo, 2018a; Rasmussen et al., 2018). A typology of climate-related migration is provided in Cross-
36 Chapter Box MIGRATE in Chapter 7. It is assumed that climate-related migration will increase in small
37 islands, however, as is the case globally, the causes, form and outcomes are highly context specific. Types of
38 climate-related migration occur across a continuum of agency from involuntary displacement at one end to
39 voluntary movement to strategically reduce risks and planned resettlement at the other end (Section 15.5.1,
40 also see Chapter 7; Birk and Rasmussen, 2014; Betzold, 2015; McNamara and Des Combes, 2015;
41 Gharbaoui and Blocher, 2016; Stojanov et al., 2017; Weir, 2020).
42
43 Studies do not provide sufficiently robust evidence to attribute the various forms of migration to
44 anthropogenic climate change directly on small islands or to accurately estimate the current number of
45 climate-related migrants (see Chapter 7). Climate events and conditions strongly interact with other
46 environmental stressors and economic, social, political and cultural reasons for migrating (robust evidence,
47 high agreement) (Birk and Rasmussen, 2014; Campbell and Warrick, 2014; Laczko and Piguet, 2014;
48 Marino and Lazrus, 2015; Connell, 2016; Weber, 2016b; Stojanov et al., 2017; Cashman and Yawson,
49 2019).
50
51 Despite difficulties with attribution, the literature establishes that climate variability and extreme events and
52 broad environmental pressures have contributed to some degree to human mobility on small islands over
53 time (medium evidence, high agreement) (Birk and Rasmussen, 2014; Campbell, 2014a; Campbell and
54 Warrick, 2014; Donner, 2015; Kelman, 2015a; Connell, 2016; Stojanov et al., 2017; Barnett and McMichael,
55 2018; Martin et al., 2018) and these studies can provide analogues from which to inform climate-migration
56 responses (Birk and Rasmussen, 2014; Kelman, 2015a; Connell, 2016).
57
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1 Similarly, studies do not provide robust evidence to project how the full range of climate drivers may
2 influence migration patterns on small islands into the future, although studies are emerging that estimate
3 populations affected as a consequence of projected SLR. Rasmussen et al. (2018) estimated current
4 populations of the world that are potentially subject to permanent inundation from projected local mean SLR
5 associated with global mean surface temperature stabilisation targets of 1.5°C, 2.0°C, and 2.5°C occurring at
6 2100. For the affected land area and population, this analysis included a subset of 58 SIDS, as defined by the
7 United Nations, for which the results are shown in Table 15.4.
8
9
10 Table 15.4: Global mean sea level rise (SLR) at 2100 projections and associated population of SIDS exposed to
11 permanent inundation for global mean surface temperature stabilisation targets of 1.5°C, 2.0°C and 2.5°C. Rasmussen
12 et al. (2018)
Stabilised Warming at 1.5°C 5th95th 2.0°C 5th95th 2.5°C 5th95th
50 50th 50th
a
2100
Percentile
Global-mean SLR (cm)
b 48 2882 56 2896 58 3793
by percentile
SIDS population
exposure (thousands) by 400 300-560 420 300-640 430 320-630
c
percentile
13 Table Notes:
14 (a) Above pre-industrial level.
15 (b) Values are centimeters above 2000 current era baseline.
16 (c) Potentially affected population due to local mean SLR. Local mean SLR projections used for individual SIDS take
17 account of variations from the global mean due to factors such as glacial isostatic adjustment, gravitational changes
18 from ice melting, deltaic subsidence and tectonic movements.
19
20
21 The aggregate figures of population that could potentially be affected by permanent inundation shown in
22 Table 15.4 and Figure 15.3 mask important differences in relative exposure between individual SIDS.
23 Further, population affected by permanent inundation does not take into account the change in the frequency
24 of ESL events and associated water-level attenuation (as per Vafeidis et al., 2019), nor does it account for
25 adaptation measures that may alleviate impacts, future population growth, or the extent to which populations
26 could adaptively migrate (Section 15.5.3). However, Rasmussen et al. (2018)'s analysis shows that
27 comparatively small changes in mean sea level can result in large increases in the frequencies of ESL events
28 and, hence, the risk of coastal flooding of inhabited land, suggesting many areas of SIDS may become
29 uninhabitable well before the time of permanent inundation (see also studies referenced in Section
30 15.3.3.1.1). A similar conclusion is drawn by Kulp and Strauss (2019) who show that land area home to 10%
31 or more of the population of many SIDS is at risk of chronic coastal flooding or permanent inundation by
32 2100.
33
34 Duvat et al. (2021a) employed an integrated systems approach to analyse future risk to habitability in atoll
35 islands, taking into account changes in various ocean and atmospheric climate drivers and a moderate
36 adaptation scenario (i.e., adaptation responses that remain similar in nature and magnitude to currently
37 observed responses). They found that, compared to present-day risk, additional risk to habitability in Male,
38 Maldives, and Fogafale, Tuvalu, is minimal under a low emissions scenario (RCP2.6) at 2050, although it
39 may become moderate for Male and high for Fogafale by 2090. Under a worse case emissions scenario (RCP
40 8.5), future risk to habitability in these two urban islands may increase slightly in 2050, but may increase to
41 moderate-to-high (for Male') and high-to-very high (for Fogafale) by 2090.
42
43 Even where settlement locations and livelihoods remain secure, an increase in health diseases, decrease in
44 the availability of potable water, and increasing exposure to extreme events may reduce habitability (Section
45 15.3.4.9.2; Campbell and Warrick, 2014; Storlazzi et al., 2018). For example, the Fijian coastal community
46 of Vunidogoloa made the decision to relocate in response to regular inundation during high tides. Raising
47 houses on stilts and constructing a seawall failed to prevent regular flood damage to buildings and the entire
48 community eventually relocated as a `last resort' adaptation measure to a site within customary land. The
49 availability of customary land for the new site was a key factor of success in this relocation example
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1 although this will not guarantee success in every case as relocation may expose communities to new risks
2 (McNamara and Des Combes, 2015; Piggott-McKellar et al., 2019a).
3
4 15.3.4.7 Culture
5
6 Small island societies have developed IKLK based responses to living in dynamic environments susceptible
7 to climate variability and extremes, which are based in broader systems of culture and heritage (high
8 confidence) (Barnett and Campbell, 2010; Lazrus, 2015; Nunn et al., 2017b; Bryant-Tokalau, 2018b; Nalau
9 et al., 2018b; Perkins and Krause, 2018). As expanded upon in Section 15.6.5 cultural resources are thought
10 to play an important role in climate change adaptation on small islands through contributing to adaptive
11 capacity and resilience (McMillen et al., 2014; Petzold and Ratter, 2015; Nunn et al., 2017b; Warrick et al.,
12 2017; Falanruw, 2018; Mondragón, 2018; Neef et al., 2018; Parsons et al., 2018; Perkins and Krause, 2018;
13 Hagedoorn et al., 2019; 2020a) (robust evidence, medium agreement). Thus, loss of culture (KR8 in Figure
14 15.5) threatens adaptive capacity.
15
16 Some studies from the Pacific suggest that climate-migration linked to reduced habitability (Section
17 15.3.4.6) can have particularly severe cultural implications in a small island context where community
18 solidarity and cohesion linked to place-based identity are important aspects of adaptive capacity (Hofmann,
19 2014; Lazrus, 2015; Warrick et al., 2017). In Federated States of Micronesia, land is owned through the
20 matrilineal system and hence puts women in the centre of decision-making. The deterioration and loss of
21 land (through saltwater intrusion, flooding, drought, erosion) not only can lead to economic deprivation but
22 it also compromises cultural identities: "Where land signifies political, social, and economic well-being,
23 becoming bereft of land cuts off an important thread of people's sense of belonging" (Hofmann, 2017, p. 82)
24 particularly for Chuuk women. Land degradation and loss involves the "interruption to the matrilineal
25 transmission of land" (Hofmann, 2017;p. 82), the loss of identities, relationships, and their customary
26 authority.
27
28 The unquantifiable and highly localised cultural losses resulting from climate drivers are less researched and
29 less acknowledged in policy than physical and economic losses (Karlsson and Hovelsrud, 2015; Thomas and
30 Benjamin, 2018a). In the Bahamas, prolonged displacement of the entire population of Ragged Island
31 following Hurricane Irma (2017) highlighted the cultural losses that can result from climate-induced
32 displacement from ancestral homelands. Threats to identity, sense of place and community cohesion resulted
33 from displacement, although all were important foundational features of the Islanders' self-initiated
34 rehabilitation efforts and eventual return. Nonetheless, non-economic losses were not accounted for by
35 policy addressing displacement (Thomas and Benjamin, 2018a). In the case of Monkey River Village in
36 Belize, coastal erosion is threatening the community's cemetery. Residents place significant spiritual and
37 emotional value on the cemetery which serves important community functions, and thus, threats to it are
38 perceived to be serious and necessary to be taken into account in any planned response (Karlsson and
39 Hovelsrud, 2015). A similar situation exists on Carriacou in the West Indies where culturally and historically
40 significant archaeological sites are being lost due to coastal erosion caused by a combination of sand mining
41 and extreme climate-ocean events exacerbated by SLR (Fitzpatrick et al., 2006).
42
43 Population and settlement concentration in coastal areas and high exposure to climate-driven coastal hazards
44 on small islands mean that threats to tangible cultural heritage (archaeological sites, buildings, historic sites,
45 UNESCO World Heritage Sites etc.) are high (Marzeion and Levermann, 2014; Reimann et al., 2018),
46 although few studies examine this issue specifically in a small island context. On the island of Barbuda,
47 archaeological sites containing important information on historical ecology and climatic shifts are at risk
48 from coastal erosion and hurricanes. This loss of heritage represents identity loss, as "learning about the past
49 is a crucial exploration of self that grounds and connects people to places" (Perdikaris et al., 2017)(p. 145).
50 Loss and damage to heritage sites may also impact tourism and thus have significant economic impacts for
51 narrow small island economies (Section 15.3.4.5).
52
53 15.3.4.8 Transboundary Risks/Issues
54
55 Inter-regional transboundary impacts are those generated by processes originating in another region or
56 continent well beyond the borders of an individual archipelagic nation or small island. Intra-regional
57 transboundary impacts originate from a within-region source (e.g., the Caribbean). Some transboundary
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1 processes may have positive effects on the receiving small island or nation, though most that are reported
2 have negative impacts (Table 15.5).
3
4
5 Table 15.5: Summary of inter- and intra-regional transboundary risks and impacts on small islands
6 [INSERT TABLE 15.5 HERE]
7
8
9 [START BOX 15.1 HERE]
10
11 Box 15.1: Key Examples of Cumulative Impacts from Compound Events: Maldives Islands and
12 Caribbean Region
13
14 Cumulative Impacts of the Compound Events of the 1998-2016 Period in the Maldives Islands
15
16 Between 1998 and 2016, the Maldives Islands were affected by three major climate events, including the
17 1997-1998 ENSO event, the 2007 flood event and the 2016 ENSO event, and by one tectonic event, the 2004
18 Indian Ocean Tsunami (Morri et al., 2015). These events illustrate the cumulative and cascading risks that a
19 series of events may cause in reef-dependent atoll contexts (Figure Box15.1).
20
21
22 The 1997-1998 ENSO event was severe in the Maldives and as a result the living coral cover dropped to
23 <10% (Bianchi et al., 2003). Recovery was still in progress in 2004 when the tsunami caused further
24 (although not quantitatively assessed (Gischler and Kikinger, 2006)) damage to the reef ecosystem. Post-
25 1998 recovery ultimately took 15 years, (i.e., longer than following the 1987 ENSO event, after which
26 recovery had only taken a few years) and also longer than in the neighbouring undisturbed Chagos atolls,
27 thereby suggesting the alteration of the recovery capacity of the reef ecosystem by human-induced reef
28 degradation and climate change (Morri et al., 2015; Pisapia et al., 2017). Mid-2016, a new ENSO event
29 occurred, which reduced living coral cover by 75% (Perry and Morgan, 2017). Future recovery of the reef
30 ecosystem, which is critical to both current livelihoods and economic activities (especially diving-oriented
31 tourism and fishing) and to long-term island persistence, will mainly depend first on the frequency and
32 magnitude of future bleaching events, which are expected to increase due to ocean warming, and second on
33 the highly variable effects of anthropogenic disturbances locally (Perry and Morgan, 2017; Pisapia et al.,
34 2017; Duvat and Magnan, 2019b).
35
36 Additionally, the 2004 Indian Ocean tsunami (Magnan, 2006) and the 2007 flood (Wadey et al., 2017)
37 caused damage totalling 62% of the country's GDP (Luetz, 2017). The tsunami also downgraded the
38 Maldives (now a middle-income country) to the Least Developed Countries category and caused within-
39 country migration, with 30,000 people (9.6% of the country's population) displaced (Republic of Maldives,
40 2009). These successive events, which had cumulative devastating effects on the reef ecosystem and
41 cascading effects on health and well-being, livelihoods and economy, highlighted the risk posed by limited
42 recovery time to the whole social-ecological system as well as the detrimental effect of local human
43 disturbances on reef recovery.
44
45
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1
2 Figure Box15.1.1: Cascading and cumulative impacts of the compound events of the 1998-2016 period in the Maldives
3 Islands.
4
5
6 Cumulative Impacts of the 2017 Hurricanes in the Caribbean Region
7
8 Among the 29 Caribbean SIDS, 22 were affected by at least one category 4 or 5 TC in 2017. These events
9 highlighted how the pre-cyclone high exposure and vulnerability of these islands and their populations has
10 caused a "cumulative community vulnerability" (Lichtveld, 2018, p. 28) that has amplified the impacts of
11 these TCs, which will in turn increase the long-term vulnerability of affected islands. The exposure of these
12 islands over their entire surface, combined with the concentration of people, and infrastructure, utilities and
13 public services in flood-prone coastal areas, inadequate housing, limited access to healthy food and
14 transportation, and unpreparedness explains widespread-to-total devastation (Shultz et al., 2018; Briones et
15 al., 2019). The destruction of transport systems (Lopez-Candales et al., 2018) and island supply chains (Kim
16 and Bui, 2019), which heavily depend on ports, roads, power and communications, made rescue logistically
17 complex, explaining the lack of freshwater, food supplies, medications and fuel on some islands for several
18 weeks after the event. This cumulative vulnerability caused "cascading public health consequences" (Shultz
19 et al., 2018, p.9), including delayed (i.e., over the next year) mortality, physical injury during the clean-up
20 and recovery phase, and increased the risk of chronic, vector-borne, contaminated water-related diseases, and
21 mental sequelae (Kishore et al., 2018; Ferre et al., 2019).
22
23 The loss of mangroves (Branoff, 2018; Walcker et al., 2019; Taillie et al., 2020) and terrestrial forests
24 (Eppinga and Pucko, 2018; Feng et al., 2018; Hu and Smith, 2018; Van Beusekom et al., 2018) exacerbated
25 the cyclone-induced economic crisis. In the most affected islands, the destruction of buildings and
26 outmigration generated a significant loss of tangible (e.g., museums) and intangible (e.g., traditional artistry)
27 cultural heritage (Boger et al., 2019). Prolonged displacement of entire island populations (e.g., Ragged
28 Island, the Bahamas; Barbuda) caused "non-economic loss and damage", including threats to health and
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1 well-being, and loss of culture, sense of place and agency (Thomas and Benjamin, 2019), which may further
2 exacerbate the long-term vulnerability of concerned communities.
3
4 In early 2020, while island communities were still recovering from the 2017 hurricanes, the COVID-19
5 pandemic caused the closure of global transportation, with devastating socioeconomic impacts on tourism-
6 dependent Caribbean economies (Sheller, 2020), illustrating how compounding crises increase island
7 vulnerability to both climate and non-climate related events.
8
9 [END BOX 15.1 HERE]
10
11
12 [START BOX 15.2 HERE]
13
14 Box 15.2: Loss and Damage and Small Islands
15
16 Loss and damage has a range of conceptualizations (Section 1.4.4.2; Cross-Chapter Box LOSS in Chapter
17 17) and is a critical issue for many small islands, closely related to issues of climate justice (Section 15.7).
18 Small islands are already experiencing an array of negative climate change impacts while climate risks are
19 projected to increase as global average temperatures rise (Section 15.3, 16.2; Cross-Chapter Paper 2).
20 Barriers and limits to adaptation also contribute to greater levels of both economic and non-economic loss
21 and damage for small islands (Sections 15.6, 16.4).
22
23 For SIDS in particular, loss and damage has negative implications for sustainable development (Benjamin et
24 al., 2018). The costs of loss and damage, particularly from extreme events, can deplete national capital
25 reserves (Noy and Edmonds, 2019). Thomas and Benjamin (2017) show how loss and damage can lead to an
26 `unvirtuous cycle of climate-induced erosion of development and resilience'. In this cycle, addressing loss
27 and damage strains limited national resources, diverting public funding and other resources to address
28 negative climate impacts. This in turn reduces resources and capacities which could be allocated to
29 adaptation, building resilience and sustainable development, thereby increasing vulnerability to climate
30 change and leading to further loss and damage where the cycle begins again. The cascading and cumulative
31 impacts of extreme events experienced in Pacific and Caribbean SIDS exemplify that this cycle may already
32 be in effect.
33
34 In addition to the strain on national resources that loss and damage currently presents, credit ratings of SIDS
35 have recently begun to include vulnerability to climate change, which may have negative impacts on their
36 abilities to borrow external funds, attract foreign investment or access concessional financing (Buhr et al.,
37 2018; Volz et al., 2020). Costs of addressing loss and damage may also affect the ability of SIDS to repay
38 external debt, thus endangering eligibility for future access to funding (Baarsch and Kelman, 2016; Klomp,
39 2017; Shutter, 2020). These factors may place SIDS in situations where they face mounting costs of climate
40 change with eroding capacities and resources to address loss and damage.
41
42 In the international policy arena, small islands - as part of Alliance of Small Island States (AOSIS) - have
43 been strong advocates for including loss and damage in the United Nations Framework Convention on
44 Climate Change (UNFCCC); highlighting the increasing and irreversible risks that climate change poses for
45 islands in particular (Roberts and Huq, 2015; Adelman, 2016; Mace and Verheyen, 2016). AOSIS, along
46 with other developing countries and groups, have advocated that there is a pressing need for finance and
47 resources to address loss and damage as well as greater integration of loss and damage in the UNFCCC and
48 the Paris Agreement, including in capacity building, technology and the global stocktake (Benjamin et al.,
49 2018; Nand and Bardsley, 2020).
50
51
52 [END BOX 15.2 HERE]
53
54
55 15.3.4.9 Key Risks in Small Islands
56
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1 15.3.4.9.1 Key Risk approach
2 This section builds on cross-chapter work led by Chapter 16 of the WGII AR6 Report aimed at identifying
3 and assessing Key Risks across sectors and regions (Section 16.5 and Supplementary Material 16.A.2). Key
4 Risks (KRs) are the risks of most pressing concern that are caused or exacerbated by climate change in a
5 given region. A KR is defined as a `potentially' severe risk, which can either be already severe or projected
6 to become severe in the future, as a result of (i) changes in associated climate-related hazards and/or the
7 exposure and/or vulnerability of natural and human systems to these hazards, and/or of (ii) the adverse
8 consequences of adaptation or mitigation responses to the risk. In line with the guidelines used in the WGII
9 AR6 Report, the identification of KRs in small islands is based on the chapter authors' expert judgment,
10 using scientific literature and five types of criteria: (1) Importance of the affected system or dimension of the
11 system, which is a value judgment left to readers to make; (2) Magnitude of adverse consequences, based on
12 their pervasiveness, degree and irreversibility, and on the potential for impact thresholds and cascading
13 effects across the system; (3) Likelihood of adverse consequences, although this probability is rarely
14 quantifiable for small islands due to limited downscaled data at a small island level; (4) Temporal
15 characteristics of the risk, including its period of emergence, persistence over time and trend; and (5) Ability
16 to respond to the risk, with the severity of the risk being inversely proportional to this ability.
17
18 15.3.4.9.2 Key Risks in small islands
19 Slow onset climate and ocean changes, and changes in extreme events, are expected to cause and/or to
20 amplify nine KRs in small islands, through both direct (e.g., decrease in rainfall will increase water
21 insecurity) and indirect, that is, cascading effects: for example, loss of terrestrial biodiversity and ecosystem
22 services will increase water insecurity, which will in turn cause the degradation of human health and well-
23 being (Figure 15.5, Table 15.6 and Table 16.A.4 in Chapter 16 Supplementary Material).
24
25 These KRs include loss of marine and coastal biodiversity and ecosystem services (high confidence) (KR1;
26 for details on KR coverage, see Section 15.3.3.1); submergence of reef islands (low confidence) (KR2;
27 Section 15.3.3.1.1); loss of terrestrial biodiversity and ecosystem services (high confidence) (KR3; Section
28 15.3.3.3); water insecurity (medium-high confidence) (KR4; Section 15.3.4.3); destruction of settlements and
29 infrastructure (high confidence) (KR5; Section 15.3.4.1); degradation of human health and well-being (low
30 confidence) (KR6; section 15.3.4.2); economic decline and livelihood failure (high confidence) (KR7;
31 Sections 15.3.4.4 and 15.3.4.5); and loss of cultural resources and heritage (low confidence) (KR8; Section
32 15.3.4.7).
33
34 Risk accumulation and amplification through cascading effects from ecosystems and ecosystem services to
35 human systems will likely cause reduced habitability of some small islands (high confidence) identified as
36 the overarching KR (KR9). Habitability is understood as the ability of these islands to support human life by
37 providing protection from hazards which challenge human survival; by assuring adequate space, food and
38 freshwater; and by providing economic opportunities, which contribute to health and well-being; recognizing
39 that both supportive ecosystems and socio-cultural conditions (i.e. beliefs and values, institutions and
40 governance arrangements, sense of community and attachment to place) play a critical role in habitability
41 (Duvat et al., 2021a). The reduction of island habitability is expected to cause increased migration, along the
42 above-mentioned involuntary displacement to planned resettlement spectrum (Section 15.3.4.6), which may
43 eventually lead to population movements from exposed areas and depopulation of some islands. This risk is
44 the highest for atoll nations, where some islands might become uninhabitable over this century (Section
45 15.3.4.6; Storlazzi et al., 2018; Duvat et al., 2021a). Despite a lack of literature assessing the risk of reduced
46 habitability in non-atoll islands, the latter are also expected to experience decreased habitability, especially
47 in their coastal areas.
48
49
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1
2 Figure 15.5: Key Risks in small islands. KR1 to 8 are interconnected as shown by arrows, which causes risk
3 accumulation leading to reduced island habitability. The main interconnections are shown in this figure: for example,
4 loss of marine and coastal and terrestrial biodiversity and ecosystem services (KR1 and KR3, respectively) are
5 projected to cause the submergence of reef islands (KR2), water insecurity (KR4), destruction of settlements and
6 infrastructure (KR5), degradation of human health and well-being (KR6), economic decline and livelihood failure
7 (KR7), and loss of cultural resources and heritage (KR8). Importantly, Key Risks result from both direct effects (e.g.
8 decrease in rainfall will increase water insecurity) and indirect effects (e.g. loss of terrestrial biodiversity and ecosystem
9 services will increase water insecurity, which will in turn cause the degradation of human health and well-being).
10
11
12 15.4 Detection and Attribution of Observed Impacts of Climate Change on Small Islands
13
14 As highlighted in AR5, detection of climate change impacts on the fragile environments of small islands is
15 challenging because of other non-climate drivers that affect small islands. Determination of attribution to
16 incremental change of climate drivers is also challenging because of the natural climate variability.
17 Therefore, there is limited scientific literature on observed impacts and attribution. A synthesis of findings
18 on the impacts of climate change (Sections 15.3.3 and 15.3.4) shows that there is more information on
19 impacts on ecosystems compared to human systems. There is high confidence in attribution to climate
20 change of impacts on the coastal and marine as well as terrestrial ecosystems (Hansen and Cramer, 2015;
21 Shope et al., 2016; van Hooidonk et al., 2016; Hoegh-Guldberg et al., 2017; Hughes et al., 2017b; Mentaschi
22 et al., 2017; Shope et al., 2017; Vitousek et al., 2017; Wadey et al., 2017; Ford et al., 2018; Hughes et al.,
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1 2018; IPCC, 2018; Storlazzi et al., 2018; Bindoff et al., 2019) and medium confidence in attribution to
2 climate change of impacts on livelihoods, economics and health (Figure 15.6; McIver et al., 2016; Eckstein
3 et al., 2018; Santos-Burgoa et al., 2018; Schütte et al., 2018; WHO, 2018).
4
5
6
7 Figure 15.6: A comparison of the degree of confidence in the detection of observed impacts of climate change on
8 tropical small islands with the degree of confidence in attribution to climate change drivers.
9
10
11 As Figure 15.6 shows there is high confidence that climate change causes changes in terrestrial ecosystems
12 as well as coral reef bleaching through increases in sea surface temperature and submergence and flooding of
13 coastal areas through sea level rise and increased wave height. With respect to casualties, settlements and
14 infrastructure loss and damage, economic and livelihood loss, although confidence in detection is high, there
15 is at present medium confidence in the attribution to climate change. Medium confidence in attribution
16 frequently arises owing to the limited research available on small island environments.
17
18
19 15.5 Assessment of Adaptation Options and Their Implementation
20
21 Since AR5, small islands have experimented with new adaptation options, which has increased the lessons
22 learnt from on-the-ground practices in these settings. Figure 15.7 shows some of the adaptation options that
23 are being experimented with in small islands. This section covers most common adaptation actions and
24 approaches across small islands and assesses the many constraints, enablers and limits to adaptation.
25 Adaptation plays also a key role in climate resilient development and the insights emerging from small
26 islands on this topic are discussed after the adaptation section.
27
28 15.5.1 Hard Protection
29
30 Seawalls have been a popular coastal protection measure on islands (Figure 15.7). An analysis of National
31 Communications shows that 28% of coastal protection actions are seawalls, followed by breakwater
32 structures and coastal protection units (Robinson, 2017a). Coastal protection infrastructure has been heavily
33 invested, for example in the Caribbean region (Mycoo, 2014b) and Cuba (Mycoo, 2014a). A similar situation
34 applies in many Indian Ocean islands, where coastal protection strategies are manifested by hard shoreline
35 structures, many of which are proving challenging to maintain (Naylor, 2015; Betzold and Mohamed, 2017;
36 Magnan and Duvat, 2018). In the Pacific the situation is different given that many islands have been
37 occupied for millennia by indigenous communities with extant knowledge for coping with adversity
38 (Granderson, 2017). The latter generally favours `soft' shoreline structures for coastal protection although
39 the building of seawalls has been rapid, especially in urban islands (Umeyama, 2012; Duvat, 2013; Magnan
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1 et al., 2018; Morris et al., 2018), and also in some rural islands (e.g., Tubuai, French Polynesia (Salmon et
2 al., 2019)).
3
4 Many rural communities have uncritically emulated structures in urban contexts built and maintained with
5 external finances. As a result, in many Pacific SIDS, seawalls have collapsed without additional funding
6 available for repairs (Nunn and Kumar, 2018; Piggott-McKellar et al., 2020; Nunn et al., 2021). Similar
7 cases have been recorded along the coast of Puerto Rico (Jackson et al., 2012) while on Indian Ocean islands
8 (e.g., Seychelles), the shorelines are littered with broken seawalls and groynes (Duvat, 2009). In Samoa,
9 seawalls close to Apia need constant investments to remain viable.
10
11 On small islands, another widespread issue with seawalls and other hard shoreline structures is that they
12 invariably shift problems of shoreline erosion and lowland inundation elsewhere (Donner and Webber,
13 2014). Even surrounding entire islands with such structures, as has happened on Male' (Maldives), is not a
14 long-term solution because of incidences of localised seawall collapse that can spread quickly if not
15 addressed immediately (Naylor, 2015). Hard structures for coastal protection will become increasingly
16 ineffective in the future, demonstrating the need for adaptation along most island coasts to become more
17 transformative than has been the case over the past few decades. In the Bahamas, it has been suggested that
18 coastal protection structures and strategies are implemented through "a rather piecemeal approach of single
19 projects and small patches, partially resulting in maladaptation by further increasing processes of erosion"
20 (Petzold et al., 2018)(p. 95). In the village of Lalomalava, Samoa, national adaptation funding was spent on
21 erecting a seawall to protect the village, but the wall was not long enough to protect the whole village,
22 leading some families and properties to face increasing impacts from large waves (Crichton and Esteban,
23 2018).
24
25 15.5.2 Accommodation and Advance as Strategies
26
27 In most small island contexts, the costs of adaptation through accommodation are prohibitive so that it has in
28 most cases not been contemplated as a widespread option. However, accommodation measures such as the
29 raising of dwellings and key infrastructure like coastal roads above ground level have been implemented to
30 reduce the impacts of flooding in some islands (Figure 15.7). In the most populous islands of the Tuamotu
31 atolls, French Polynesia, where between 48 and 98% of dwellings have already experienced flooding since
32 the 1980s, elevated houses with floors built 1.5 m above ground level are subsidised by the Government as
33 part of Risk Prevention Plans (Magnan et al., 2018). Despite this incentive, the opposition of the local
34 authorities and population to these plans (which also include constraining setback guidelines) considerably
35 limited implementation, hence elevated houses only represent 7% of the total housing stock. In the
36 Philippines (Tubigon) and Indonesia (Jakarta area) residents have elevated their houses by building stilted
37 houses or raising the floor using coral stones to face increased flooding (Jamero et al., 2017; Esteban et al.,
38 2020). Also, in Puerto Rico houses have been raised to address flooding (Lopez-Marrero, 2010).
39
40 In some small island settings, land reclamation (i.e., land gain through infilling) has been implemented for
41 decades to allow for infrastructure construction and to address land shortages arising from high population
42 growth. For example, land reclamation in Port of Spain, the capital city of Trinidad, has long been used as a
43 solution space to meet land for housing, industrial development and infrastructure provision (Mycoo,
44 2018b). Likewise, one third of the land area of Male', the capital island of the Maldives, results from land
45 reclamation (Naylor, 2015). Land reclamation is also common in Pacific atoll countries and territories, where
46 it occurs both in urban islands facing high population pressure, such as South Tarawa, Kiribati (Biribo and
47 Woodroffe, 2013), Funafuti Atoll, Tuvalu (Onaka et al., 2017), and Rangiroa Atoll, French Polynesia (Duvat
48 et al., 2019b), and in rural islands, e.g., Takapoto and Mataiva atolls, French Polynesia (Duvat et al., 2017b).
49 In some cases, land reclamation has paved the way for land raising, which is increasingly considered to adapt
50 to SLR in small islands contexts (Figure 15.7). For example, since the 1990s, the capital area of the Maldives
51 has been expanded through the construction of a large new island, Hulhumale', which is still under
52 construction and is built 60 cm higher than Male' to take into account SLR (Hinkel et al., 2018; Brown et al.,
53 2020). More generally, in the Maldives, the 2004 Indian Ocean Tsunami has boosted island raising as part of
54 the "safe island development programme" (Shaig, 2008). Recent studies suggest that land and island raising
55 have some potential in small islands, especially in urban high-value areas where this can generate substantial
56 revenues through the sale or lease of new land, and therefore leverage public adaptation finance (Bisaro et
57 al., 2019).
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1
2 15.5.3 Migration
3
4 Migration, including planned resettlement, is increasingly occurring in small islands to intentionally respond
5 to or prepare for climate change impacts (Figure 15.7; Magnan et al., 2019). There is currently limited
6 evidence and low agreement in the literature as to whether migration of various types is an effective strategy
7 to adapt to localised impacts of climate change, as outcomes are highly context specific (Donner, 2015;
8 McNamara et al., 2016; Hermann and Kempf, 2017; McMichael et al., 2019; Piggott-McKellar et al., 2019a;
9 Tabe, 2019; Bertana, 2020; Weir, 2020).
10
11 In-situ adaptation options are frequently the preference of communities over resettlement (Jamero et al.,
12 2017) and in many documented cases, relocation both planned and autonomous is an adaptation option of
13 last resort due to high economic and socio-cultural cost (McNamara and Des Combes, 2015; Jamero et al.,
14 2017; Crichton et al., 2020). In small islands, there is medium evidence and high agreement that the degree
15 of migrant agency and choice in decisions about whether to move, where, when and how is an important
16 determinant of success and therefore `adaptiveness' (see Cross-Chapter Box MIGRATE in Chapter 7;
17 McNamara and Des Combes, 2015; Hino et al., 2017; McMichael et al., 2019; Piggott-McKellar et al.,
18 2019a; Bertana, 2020) . Two case studies of community relocation in Fiji (Denimanu and Vunidogoloa
19 villages) recommend that participatory inclusion of all social groups in the relocation planning process,
20 including in planning for livelihood sustainability in new locations, should be ensured in future planned
21 community relocation to foster positive adaptive outcomes (Piggott-McKellar et al., 2019a).
22
23 There are few examples of highly `successful' and therefore adaptive international resettlement or relocation
24 in response to environmental pressures in history. For example, the experiences of Gilbertese resettled in the
25 Solomon Islands highlight that tensions with host communities over land and resource rights and limited
26 knowledge of new environments (such as where communities previously reliant on marine resources are
27 resettled in high island locations) can create new vulnerabilities (Donner, 2015; Weber, 2016a; Tabe, 2019).
28 Even where gradual international relocation is supported and planned through policy as in the case of
29 Kiribati's "migration with dignity" strategy, strong cultural connection to land and uncertainty about life in
30 receiving communities in Australia and New Zealand means that many remain opposed to indefinite or
31 permanent migration (Allgood and McNamara, 2017; Hermann and Kempf, 2017). The same challenges
32 could apply where domestic migration occurs between significantly different cultural, social and physical
33 environments. However, planned migration for employment or education can reduce exposure in sending
34 locations and spread risk through expanding economic opportunities and providing remittances, thus having
35 inadvertent adaptation outcomes (Campbell, 2014a). Policies which support migration for employment by
36 the most vulnerable - those that may wish to migrate but lack the resources to do so - may offer an adaptive
37 strategy to environmental pressure, particularly where these incorporate adequate preparedness for life in
38 host communities (Luetz, 2017; Curtain and Dornan, 2019; Drinkall et al., 2019). Research from the
39 Maldives suggests that women and men do not possess equal capacities to use mobility as a strategy to adapt
40 to climate change, with women less able to employ migration as an adaptation strategy due to gender roles,
41 social expectations, economic structures, political laws and religious doctrines, and gender norms and
42 cultural practices (Lama, 2018).
43
44 Forced relocation, involuntary displacement and low-agency migration (for example, due to low migrant
45 financial resources, or limited participation in migration planning) is commonly associated with unsuccessful
46 outcomes and can therefore be considered an impact of climate change rather than an adaptation strategy
47 (Weber, 2016a; Thomas and Benjamin, 2017; Tabe, 2019). Resettlement of households, communities and
48 larger island populations is increasingly discussed in the context of loss and damage when in-situ adaptation
49 limits are thought to be reached. Limited data and research relating to adaptation limits, transformational
50 adaptation, tolerable and intolerable risk levels in small islands, and limited ability to directly attribute
51 climate change to migration decisions (in the context of both slow onset changes and extreme events) mean
52 that policy applications are currently limited (Thomas and Benjamin, 2018b; Handmer and Nalau, 2019;
53 Nand and Bardsley, 2020).
54
55 15.5.4 Ecosystem-based Measures
56
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1 Small islands have focused increasingly on ecosystem-based adaptation (EbA) approaches and other Nature-
2 Based Solutions that bring benefits both for the ecosystems and communities (Figure 15.7; Giffin et al.,
3 2020). There is robust evidence on implementation of EbA approaches across small islands, yet medium
4 agreement on the exact benefits of these activities (Mercer et al., 2012; Doswald et al., 2014; Nalau et al.,
5 2018a) given the difficulties in quantifying benefits and the absence of monitoring and evaluation
6 frameworks (Doswald et al., 2014). Traditionally, EbA activities, especially at national and regional scales,
7 have predominantly focused on restoring or conserving coastal and marine ecosystems (e.g., coral reefs,
8 mangrove forests and seagrass meadows), with less emphasis upon the services provided by natural inland
9 forests (Mercer et al., 2012). Incorporation of forests is however increasing, in most cases as components of
10 ridge to reef (Figure 15.4) (or DDR) projects (limited to medium evidence), and is geared towards integrated
11 watershed management to establish downstream water security, erosion control and ultimately to protect the
12 health of coral reef ecosystems (Förster et al., 2019).
13
14 Additionally, some islands are constructing climate-smart development plans such as improved management
15 of existing and newly established protected areas, restoration of riparian zones, urban forests/trees, sub urban
16 and peri urban home gardens, and improved agroforestry practices towards increasing resilience to changing
17 climate conditions, wildfires as well as decreasing food insecurity (e.g., Pedersen et al., 2016; McLeod et al.,
18 2019). Paired terrestrial and marine protected areas have shown that forest conservation and rehabilitation
19 yield better outcomes for coral health as forests stabilize soils and prevent erosion and sequester groundwater
20 pollutants (limited to medium evidence, high agreement) (Carlson et al., 2019). The success of protected
21 areas is however undermined by weak governance due in part to limited financial resources which
22 undermine management and the enforcement of regulations governing activity within them (Schleicher et al.,
23 2019).
24
25 Since the 1990s, artificial reefs have been increasingly used in small islands to support reef restoration and
26 reduce beach erosion, especially in the Caribbean region (e.g., Dominican Republic, Antigua, Grand
27 Cayman, Grenada) and Indian Ocean (Maldives, Mauritius) (Fabian et al., 2013; Reguero et al., 2018). They
28 have been more or less successful in reducing the destructive impacts of extreme events, depending on their
29 technical characteristics and the local context. For example, while it resisted the waves generated by
30 hurricanes Georges and Mitchell in 1998, the artificial reef (Reef Ball breakwater type) implemented at Gran
31 Dominicus Resort, Dominican Republic, did not prevent significant beach erosion. In contrast, the coral reef
32 restoration project implemented to "build a beach" on the resort island of Ihuru, North Male' Atoll, Maldives,
33 was successful as it allowed beach expansion and prevented the erosive impacts of the 2004 Indian Ocean
34 Tsunami on the beach (Fabian et al., 2013).
35
36 Over the past decades, beach nourishment has been implemented in small islands either to reduce beach
37 erosion (e.g., in tourist areas), or to protect critical human assets (e.g., roads) that are highly exposed to
38 storm waves. It has been increasingly used to maintain beaches in the islands of the Maldives (Shaig, 2011),
39 and in Barbados (Mycoo, 2014b). However, islands have limited sand stocks and sediment extraction can
40 aggravate risks and/or accelerate ecosystem degradation if implemented without the necessary precautions.
41
42 In designing and implementing EbA, IKLK have high relevance especially amongst Pacific small islands as
43 many communities are remote and still rely on ecosystems for their livelihoods (Nalau et al., 2018b; Narayan
44 et al., 2020). In Fiji, IKLK have informed EbA projects by identifying native species suitable to strengthen
45 the coastal environment to reduce coastal erosion and flooding in the villages (Nalau et al., 2018b). Whole-
46 of-island approaches, like Lomanu Gau in the Gau Island in Fiji, try to foster integrated management
47 practices in small islands that are based on shared governance of resources, and understanding the
48 interlinkages between sectors and ecosystems (Remling and Veitayaki, 2016). In the Caribbean, EbA
49 approaches are somewhat absent in national and regional programmes and plans, yet at the local scale EbA
50 strategies are used increasingly with implementation mostly led by NGOs (Mercer et al., 2012).
51
52 EbA approaches have many benefits but also face several challenges and limits. Biophysical limits can make
53 some EbA and Nature-based Solutions ineffective: coral reefs are unlikely to withstand increased
54 temperatures, reducing the effectiveness of coral reef based EbA options under higher temperature scenarios
55 (Barkdull and Harris, 2018; Cornwall et al., 2021). Likewise, many other coastal and marine ecosystems,
56 such as mangroves, face severe limitations with increasing sea levels and other climate impacts (Morris et
57 al., 2018; Thomas et al., 2021).
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1
2
3
4 Figure 15.7: Adaptation measures implemented to reduce coastal risks in small islands. Panel 1 provides examples of
5 implementation of different types of measures aimed at reducing coastal erosion and flooding. The measures include no
6 response (no intervention, widespread in small islands), hard protection through the construction of engineering-based
7 structures, accommodation through dwelling and infrastructure raising, planned retreat, advance (i.e. especially island
8 raising) and ecosystem-based measures, in three small island regions, the Indian and Pacific Oceans and Caribbean. It
9 highlights the prevalence of no response, hard protection and the increasing use of ecosystem-based measures. Based on
10 the example of two beach sites in Mauritius (Mon Choisy in the north and Saint-Félix in the south), panel 2 shows that
11 the measures used at a given coastal site evolve over time (e.g., from no response to hard protection, and then planned
12 retreat and ecosystem-based measures) and that recent DRR (Saint-Félix) and adaptation (Mon Choisy) projects often
13 combine several types of measures, including retreat and ecosystem-based measures (Duvat et al., 2020a). Together,
14 panels 1 and 2 emphasize the diversity and increasing complexity of the measures implemented in small islands.
15
16
17 15.5.5 Community-based Adaptation
18
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1 Community-based Adaptation (CBA) is best described as a "community-led process based on meaningful
2 engagement and proactive involvement of local individuals and organisations" (Remling and Veitayaki,
3 2016)(p. 380). Enabling CBA projects to succeed relies on gaining a good understanding of the socio-
4 political context within which the communities operate, including such key issues as land tenure
5 arrangements and ownerships, gender, and decision-making processes that operate on the ground (Nunn,
6 2013; Buggy and McNamara, 2016; Crichton and Esteban, 2018; Delevaux et al., 2018; Nalau et al., 2018b;
7 Parsons et al., 2018; McNamara et al., 2020; Piggott-McKellar et al., 2020).This also includes the broader
8 and often more urgent development issues that impact on communities' wellbeing (Piggott-McKellar et al.,
9 2020). Community-based projects demonstrate in the Pacific that communities' vulnerabilities, priorities and
10 needs might be a better and more effective entry point for climate adaptation than framing projects solely
11 around climate change (Remling and Veitayaki, 2016; Weir, 2020).This is supported by a recent review of
12 32 CBA initiatives in the Pacific where initiatives that were locally funded and implemented were more
13 successful than those with external international funding (McNamara et al., 2020). Initiatives that integrated
14 EbA and climate awareness raising also performed better (McNamara et al., 2020).
15
16 While CBA approaches to adaptation projects can increase community ownership and commitment to
17 project implementation, these can also face challenges. In Pele Island, Vanuatu, implementation of CBA
18 projects has experienced significant failures due to elite capture of project management, internal power
19 dynamics within communities, and different priorities of communities living across the island that were
20 supposed to be all responsible for implementing whole-of-island projects (Buggy and McNamara, 2016).
21 Similarly, in Samoa, consultations with community leaders led to the misplacement of a revetment wall that
22 increased flooding in the area against engineering advice (McGinn, 2020). Also, community-scale might not
23 be always the best fit if the best scale to leverage adaptation is across catchment or whole-of-island scale
24 (Buggy and McNamara, 2016; Remling and Veitayaki, 2016).
25
26 15.5.6 Livelihood Responses
27
28 Communities across small islands are adapting to the impacts of climate change across a range of livelihood
29 activities. Coastal fishers have adapted by employing several activities ranging from diversification of
30 livelihoods to changing fishing grounds and considering weather insurance (Blair and Momtaz, 2018;
31 Lemahieu et al., 2018; Karlsson and McLean, 2020; Turner et al., 2020). In Antigua and Vanuatu, fishers
32 have undertaken adaptation in response to increases in air and ocean temperature, increases in wind and
33 changes in rainfall. In Antigua, adaptation strategies amongst coastal fishers have included investments in
34 improved technologies and equipment, changing fishing grounds, and seeking better training and education
35 (Blair and Momtaz, 2018). In Efate (Vanuatu) the majority (87%) of the fishermen used livelihood
36 diversification as an adaptation strategy whereas 53% also searched for new fishing areas as a result of the
37 changing conditions (Blair and Momtaz, 2018). In Southwest Madagascar, due to deteriorated reef
38 conditions, coastal fishermen now go further offshore to catch fish or have adapted their fishing techniques,
39 while others closer to the tourism markets, have opted for livelihood diversification (Lemahieu et al., 2018).
40 Coastal fishers in the Dominican Republic have also diversified their livelihoods and use local knowledge in
41 changing fishing practices and locations depending on environmental conditions (Karlsson and McLean,
42 2020). In the future, increased inland rainfall could for example provide new areas for inland aquaculture in
43 the Solomon Islands as an adaptation strategy and also reduce pressure from coastal fishing (Dey et al.,
44 2016).
45
46 In the agricultural sector in Jamaica, adaptation strategies include varying expenditure on inputs (e.g.,
47 fertilizers, chemicals, labour), diversifying cropping patterns, expanding or prioritising other cash crops (e.g.,
48 fruits and vegetables), engaging in small-scale livestock husbandry (Guido et al., 2018), and investing in
49 irrigation technologies due to increased drought and infrequent rainfall (Popke et al., 2016). In many higher
50 elevation islands within the Pacific, including Vanuatu and Fiji, communities continue to use to varying
51 degrees traditional adaptive strategies designed to reduce their vulnerability to tropical cyclones. These
52 include planting a diversity of different crops within household and communal gardens, locating gardens in
53 different areas within their customary lands to ensure that not all crops are destroyed due to an extreme
54 event, and the storage, and preservation of certain foodstuffs (so-called famine foods) (Campbell, 2014b;
55 McMillen et al., 2014; Le Dé et al., 2018; Moncada and Bambrick, 2019).
56
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1 Given changes in climatic conditions, in Puerto Rico women in the coffee industry are now forming their
2 own "micro-clusters" of complementary activities, such as rebuilding of public spaces, running
3 environmental education programmes for children, and opening new commercial enterprises (e.g., coffee
4 shops, and food products) that do not rely on traditional coffee supply chains or government assistance
5 (Borges-Méndez and Caron, 2019). Such alternative livelihood strategies parallel those undertaken by
6 Pacific women working on various local-level climate change adaptation and environmental projects
7 throughout small island nations of the Pacific. Women report testing and using adaptive strategies informed
8 by IKLK, but which are being modified to suit the changing environmental conditions they are encountering
9 and those projected in the future. This includes harvesting rainwater during droughts, planting native plants
10 along coastlines to prevent erosion and flooding, developing plant nurseries, experimenting with growing
11 salt-tolerant (taro) crops, and relocating crop cultivation inland (McLeod et al., 2018).
12
13 The tourism sector is increasingly a major source of cash-based livelihoods across small islands. Despite the
14 high vulnerability and sensitivity of island tourism to climate change at a national scale (Scott et al., 2019),
15 there is evidence from the South Pacific that local tourism operators' adaptive capacity is high due to socio-
16 cultural factors. In Samoa, adaptive capacity consists of accommodation providers' social networks,
17 resources, past experiences and understanding of environmental conditions, and remittances as a form of
18 informal insurance (Parsons et al., 2017). The adaptive capacity of Tongan tour operators is strengthened by
19 high climate change awareness, strong social networks and remittances as well as perceived high resilience
20 against climate change (van der Veeken et al., 2016).
21
22 Evidence from Vanuatu shows that climate risk to tourism destinations is influenced by multiple,
23 interconnected economic, socio-cultural, political, and environmental factors suggesting that holistic
24 approaches are needed to reduce risk and avoid negative knock-on effects (Loehr, 2019). Tourism can
25 strengthen mechanisms that reduce vulnerability and increase adaptive capacity of the wider destination,
26 such as providing adaptation finance, investing in education and capacity building, and working with nature
27 (Loehr, 2019).Examples include numerous EBA initiatives in the Caribbean including Marine Protected
28 Areas in St. Lucia and Jamaica (Mycoo, 2018a). In Vanuatu, tourism businesses are engaged in establishing
29 Marine Protected Areas to address multiple risks from climate change, population growth and development
30 (Loehr et al., 2020). In the Seychelles, coral restoration programmes and mangrove reforestation are
31 promoted through public-private partnerships, generating new opportunities for wetland-tourism livelihoods
32 (Khan and Amelie, 2015).
33
34 The willingness of tourism businesses to finance adaptation measures varies. Islands have developed
35 building codes which consider impacts from sea level rise but these are often not enforced enforced (Hess
36 and Kelman, 2017). In cases where tourist resorts have been part of climate adaptation projects, such as
37 funding for hard coastal protection infrastructure, the resort owners find that these diminish the aesthetics of
38 the beach destination (Crichton and Esteban, 2018). Adaptation taxes and levies imposed on tourism can
39 provide funding (Mycoo, 2018a) as The Environmental Protection and Tourism Improvement Fund Act,
40 2017 of British Virgin Islands shows (Smith, 2017). A lack of interaction between tourism and climate
41 change decision makers is a commonly identified issue (Becken, 2019; Mahadew and Appadoo, 2019; Scott
42 et al., 2019). A number of adaptation measures are recommended in the literature such as increasing climate
43 change research, education and institutional capacities; product and market diversification away from coastal
44 tourism to include terrestrial-based experiences and heritage tourism, and mainstreaming adaptation in
45 tourism policies and vice versa (e.g., to include appropriate planning guidelines for tourism development,
46 coastal setbacks and environmental impact assessments (Mycoo, 2018a; Becken et al., 2020) Thomas et al.,
47 2020; van der Veeken et al., 2016).
48
49 15.5.7 Disaster Risk Management, Early Warning Systems and Climate Services
50
51 Disaster risk management (DRM) investments in small islands are commonly framed as reducing climate
52 change-driven risk and contributing to sustainable development (Johnston, 2014; Mercer et al., 2014a;
53 Kuruppu and Willie, 2015). Examples include strengthening the capacity of National Meteorological and
54 Hydrological Services (NMHS ) to deliver effective (WMO et al., 2018); nurturing community-based DRM
55 to build social capital (Blackburn, 2014; McNaught et al., 2014; Gero et al., 2015; Handmer and Iveson,
56 2017; Chacowry et al., 2018; De Souza and Clarke, 2018; Currenti et al., 2019; Cvitanovic et al., 2019;
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1 Hagedoorn et al., 2019), as well as processes that integrate IKLK with science (Hiwasaki et al., 2014; Carby,
2 2015; Bryant-Tokalau, 2018a; CANARI, 2019).
3
4 Many small islands, especially those with the highest risks and the least resources, remain highly challenged
5 in building and sustaining integrated, people-centred, end-to-end early warning systems that are fully
6 functional across the four interrelated components of EWS. Warning dissemination and communication, and
7 disaster preparedness and response capacities are particular components of EWS requiring strengthening in
8 SIDS (WMO, 2020). More recent assessments of early warning capabilities in the Caribbean highlight
9 improvements in EWS for weather, water and climate over time (WMO et al., 2018; Mahon et al., 2019).
10 However, progress has been uneven across hazards, governance levels and spatial and temporal scales, with
11 more advanced development of some sub-systems and EWS pillars than others. Significant progress has
12 been made in the area of detection, monitoring, analysis and forecasting of severe weather systems but there
13 is a need to strengthen this area for other climate-related hazards such as wildfires, localised intense rainfall,
14 floods, as well as heatwaves and droughts which become more important in a changing climate. Assessments
15 also point to specific deficiencies including significant gaps in the area of disaster risk knowledge -
16 particularly the development of risk assessments, the variable capacity for interpreting scientific warning
17 products across states, as well as effective communication of warning messages to populations at risk
18 (Lumbroso et al., 2016; WMO et al., 2018).
19
20 There is increasing recognition and commitment at global (Section 3.6.3.2.4; WMO, 2014; UN, 2015c; UN,
21 2015b; UN, 2015a), regional (CCCCC, 2012; CDEMA, 2014; SPC, 2016; SPREP, 2017; CIMH et al., 2019)
22 and national levels (SPREP, 2016a; WMO, 2016a) of the importance of climate services in supporting
23 adaptation decision making in small islands (medium evidence, high agreement). A number of SIDS-focused
24 climate service programmes have emerged, especially in the Caribbean and Pacific (Group, 2015; Martin et
25 al., 2015; SPREP, 2016b; WMO, 2016b; WMO, 2018a; WMO, 2018b) and at least one SIDS Dominica -
26 has been prioritised as a pilot implementation country under the Global Framework for Climate Services
27 (WMO, 2016a). As is the case globally, climate services focused on decision-making at seasonal (36
28 month) timescales has thus far been the focus of investment in small islands. Less attention has been given to
29 investments in and assessments of climate services for decision making at longer timescales (Vaughan et al.,
30 2018).
31
32 Studies from the Caribbean (Dookie et al., 2019; Mahon et al., 2019) and Indian Ocean (Hermes et al.,
33 2019), have found that NMHSs and regional intergovernmental bodies face capacity challenges in
34 translation, transfer, and facilitation of the use of climate information to various end user groups. In many
35 small island contexts a gap remains between investments in data quality and information services and uptake
36 and use in risk reduction by policy and decision makers (Dookie et al., 2019). Bringing policy makers and
37 users together to guide investments in climate information services is recommended, as is provision of
38 dedicated resources to develop applicable tools and products that turn data and information services into risk
39 reduction measures (Dookie et al., 2019; Haines, 2019).
40
41 Many of the outlined Key Risks (Section 15.3.4.9) can be addressed through the variety of adaptation
42 options outlined in the previous sections in the context of small islands (Table 15.6, Supplementary Material
43 15.1). Whereas some of these adaptation options are widespread (e.g., hard protection, reforestation or the
44 creation of MPAs), others (e.g. accommodation, health awareness raising and training) have been little
45 experimented with to date in small island contexts. Although most of these adaptation options provide
46 diversified co-benefits to small island communities, there is still limited evidence with regard to their
47 effectiveness in reducing climate change impacts. While some of them respond directly to a Key Risk or a
48 number of Key Risks (Table 15.6), others can be understood as overarching options that, for example, build
49 adaptive capacity of communities and organizations and enable these actors to respond to a variety of Key
50 Risks in an effective manner (see Supplementary Material 15.1).
51
52
53 Table 15.6: Adaptation options per Key Risk in small islands. This table summarizes risk-oriented adaptation options,
54 their level of implementation, enablers and effectiveness in reducing exposure and vulnerability, co-benefits and
55 disbenefits in small islands. For Key Risk 2 (submergence of reef islands), not included, adaptation options are the
56 same as for Key Risk 5.
57 [INSERT TABLE 15.6 HERE]
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1
2
3 15.6 Enablers, Limits and Barriers to Adaptation
4
5 Since AR5, more literature has emerged on barriers, limits and enablers to climate change adaptation across
6 small islands. Here, we cover barriers, limits and enablers as they relate to key themes across small islands
7 and adaptation.
8
9 15.6.1 Governance
10
11 Specific governance-related barriers for effective adaptation include: lack of coordination between
12 government departments and sectors and limited policy integration (Scobie, 2016; Robinson, 2018b), lack of
13 ownership of adaptation implementation in cases where communities or national governments have not been
14 part of the adaptation decision process (Conway and Mustelin, 2014; Kuruppu and Willie, 2015; Prance,
15 2015; Nunn and Kumar, 2018; Parsons and Nalau, 2019), and difficulties in integrating IKLK in adaptation
16 initiatives. Specific barriers to effective sustained adaptation in the Pacific include variable climate change
17 awareness among decision-makers, and the preference for short-term responses rather than longer-term
18 transformative ones (Nunn et al., 2014). These barriers also stem from donors' preferencing their own
19 priorities that do not necessarily fit the country priorities or context (Conway and Mustelin, 2014; Kuruppu
20 and Willie, 2015; Prance, 2015), which has led to increasing calls for effective community/cultural
21 engagement in adaptation, especially through CBA and EbA (Nalau et al., 2018b). In cases where recovery
22 efforts are framed as purely a matter of infrastructure other important aspects, such as livelihoods and
23 gender, are more easily overlooked in adaptation (Turner et al., 2020).
24
25 In the Caribbean small islands such as Jamaica and St. Lucia, and also in the Pacific, barriers to
26 mainstreaming adaptation include competing development priorities, the absence of planning frameworks or
27 `undetected' overlaps in existing frameworks, serious governance flaws linked to the prevalence of
28 corruption and corrupt people in political and public life, and insufficient manpower and human resources,
29 linked to countries' financial capacity (Robinson, 2018b). In addition, the lack of strong governance
30 mechanisms for urban planning have contributed to urban sprawl and expansion that has increased the
31 number of informal settlements, which together with population growth are driving Caribbean small islands
32 to their limits (Enríquez-de-Salamanca, 2018; Mycoo, 2018a; Mycoo, 2018b). In the Pacific, only a few
33 countries have embedded climate change adaptation in existing legislation despite the overall regional
34 agreement to A New Song for Coastal Fisheries - Pathways to Change: the Noumea Strategy' to improve
35 coastal fisheries management in a changing climate (Gourlie et al., 2018). Many climate change specific
36 initiatives across small islands have a unidirectional focus on climate risks and shift limited resources away
37 from other important development objectives (Baldacchino, 2018). Local level plans are often overlooked:
38 for example, in Mauritius, local level climate adaptation plans are currently nearly non-existent while district
39 councils have rarely been successful in even accessing international adaptation finance (Williams et al.,
40 2020). In Samoa, several national level programs on adaptation have had difficulties in engaging with the
41 local level even if the decision-making powers on actual land management sit within the communities
42 (McGinn and Solofa, 2020).
43
44 Adaptation governance is also complicated further by the multitude of stakeholders involved, with differing
45 agendas and priorities. In the Bahamas, private properties have significant say in how and what adaptation
46 measures they decide to pursue and are not well regulated, with the tourism sector in particular dominated
47 mainly by external investors (Petzold et al., 2018). Social organisations, such as the churches, that have
48 significant influence in many Oceanic countries, are engaging in climate change discussions and governance.
49 Many churches report, however, being constrained to act on climate adaptation due to lack of financial
50 resources, low levels of professional knowledge on adaptation, and their members not perceiving climate
51 change as an urgent risk (Rubow and Bird, 2016). Actors such as military services in the Indian and Pacific
52 Oceans also control a high number of assets in vulnerable locations and will need to integrate climate
53 information into adaptive planning in the future (Finucane and Keener, 2015).
54
55 Low technical capacity, and poor data availability and quality are reported as limiting adaptation in
56 Caribbean small islands such as Dominica, and St. Vincent and the Grenadines (Smith and Rhiney, 2016;
57 Robinson, 2018a) and Trinidad and Tobago (Mycoo, 2020). These factors are, however, secondary to the
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1 lack of finances, which is seen as a fundamental limit (Charan et al., 2017; Robinson, 2018a; Williams et al.,
2 2020). This was also reported in the Seychelles, despite its success with innovative financing streams and
3 being a leader in the Indian Ocean in this regard (Robinson, 2018a).
4
5 Limited regional cooperation across sub-national island jurisdictions (jurisdictions with semi-autonomous
6 status) along with limited regional-scale climate information are also stymying action (Petzold and Magnan,
7 2019). This is a concern given the need for pooled governance in response to capacity constraints across
8 small jurisdictions (Dornan, 2014; Kelman, 2018). There is also an insufficient understanding of the role of
9 regional and international actors such as the Caribbean Community Climate Change Centre and the Global
10 Environment Facility, respectively (Middelbeek et al., 2014). Sometimes external pressure and, for example,
11 trans regional trade agreements are "useful for reducing unsustainable local socio-political arrangements" as
12 seen in the Solomon Islands regarding fisheries management within the concept of Blue Economy (Keen et
13 al., 2018, p. 338). Similarly, in Samoa, the World Bank's Pilot Program for Climate Resilience (PPCR) and
14 Adaptation Fund's Enhancing Resilience of Samoa's Coastal Communities to Climate Change, illustrate
15 successful examples of multi-level governance due to their programmatic and pragmatic approaches versus
16 project-based approaches (McGinn and Solofa, 2020). Enabling factors in these programmes relate to
17 strategic placements of funds and responsibilities in the relevant ministries, alignment with national priorities
18 and pre-existing plans, pooling funding to fill existing finance gaps, and increased awareness across scales
19 and departments of synergies and gaps between different initiatives (McGinn and Solofa, 2020). Initiatives
20 such as the Pacific Adaptive Capacity Framework (Warrick et al., 2017) and regional strategies such as the
21 Framework for the Disaster and Climate Resilient Development in the Pacific (FRDP) enable the localising
22 of climate adaptation into cultural contexts in an integrated manner (SPC, 2016).
23
24 Countries including the Seychelles and Maldives have developed national climate change plans that
25 recognize linkages to food security, health and disaster risk reduction, although these-face significant
26 resourcing issues when it comes to implementation (Techera, 2018). National level plans, such as National
27 Adaptation Plans of Action (NAPAs), increasingly could include local government engagement and have a
28 stronger focus on urban centres and adaptation (Mycoo, 2018a). Building codes act as supportive enablers
29 for adaptation governance: requiring more hurricane-resistant housing in the Caribbean, including incentives
30 for informal settlements to build in a more resilient manner, can achieve multiple development and
31 adaptation outcomes (Mycoo, 2018a). In Dominica, a Climate Resilience Executing Agency of Dominica
32 (CREAD) established in 2019, aims to enable stronger climate resilience by bringing all sectors and services
33 together for more effective coordination (Turner et al., 2020). Improvements in cross sectoral and cross
34 agency coordination are creating opportunities for improved disaster preparedness and resilience measures in
35 Vanuatu (Webb et al., 2015). A range of mechanisms also exists in the tourism industry: adaptation taxes
36 and improved building regulations could reduce risk drastically for example in the Caribbean region (Mycoo,
37 2018a).
38
39 15.6.2 Health-Related Adaptation Strategies
40
41 The term `health systems' refers to the organisation of people, institutions, and resources that work to protect
42 and promote population health. The two components of health systems are public health and health care;
43 adaptation is needed in both to develop climate-resilient health systems (WHO, 2015). Adaptation measures
44 focus on each of the building blocks of health systems, including leadership and governance; a
45 knowledgeable health workforce; health information systems; essential medical products and technologies;
46 health service delivery; and financing. Many small island states have policies to manage climate-sensitive
47 health risks, although Ministries of Health are largely unprepared to adapt to a changing climate because few
48 programmes take climate change into account (McIver et al., 2016). Particularly vulnerable groups, such as
49 Indigenous peoples, are often inadequately represented in adaptation planning processes and implementation,
50 resulting in less effective interventions (Jones, 2019).
51
52 A range of climate-sensitive diseases pose threats to island communities. A vulnerability and adaptation
53 assessment conducted in Dominica identified vector-, water- and food-borne diseases and food security as
54 priority threats from climate change (Schnitter et al., 2019). Short-term adaptation options include
55 strengthening solid waste management and enforcing current legislation; increasing public awareness;
56 training health sector staff; improving the reliability and safety of water storage practices; improving climate
57 change and health data collection methods and enhancing environmental monitoring; enhancing the
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1 integration of climate services into health decision-making; strengthening the organisational structure of
2 emergency response; and ensuring sufficient resources and surge capacity. Longer-term adaptation options
3 include developing early warning and response systems for climate-sensitive health risks; enhancing data
4 collection and information flow; increasing the capacity of laboratory facilities; and developing emergency
5 plans. For example, rainfall is the best environmental predictor of malaria in North Guadalcanal, Solomon
6 Islands, leading to the development of an early warning tool that could increase resilience to climate change
7 (Smith et al., 2017; Jeanne et al., 2018).
8
9 In small island states, water, sanitation, and hygiene infrastructure are particularly vulnerable to climate
10 change, with impacts on the burden of diarrheal diseases. The resilience of types of sanitation infrastructure
11 in urban and rural households in the Solomon Islands differ under scenarios of increased rainfall and
12 flooding versus decreased rainfall and drought, reinforcing the centrality of taking the local context into
13 account during adaptation decision-making (Fleming et al., 2019). Healthcare facilities, including hospitals,
14 clinics, and community care centres, are vulnerable to extreme weather and climate events, such as flooding
15 and TCs, and to climate-related outbreaks of infectious diseases that overwhelm their capacity to provide
16 critical services (WHO, 2020). These facilities may lack functioning infrastructure and trained health
17 workforce, and be predisposed to inadequate energy supplies, and water, sanitation, and waste management
18 services. Adaptation is needed to build resilience and contribute to environmental sustainability.
19
20 Many major health care facilities in small island states are in exposed coastal areas and have limited ability
21 to provide health services during disasters when services are most needed (WHO, 2018). For example, in
22 Vanuatu, TC Pam in 2015 severely damaged two hospitals, 19 health care centres, and 50 healthcare
23 dispensaries in 22 affected islands (Kim et al., 2015). A Smart Hospital Initiative in the Caribbean focuses
24 on improving hospital resilience, strengthening structures and operations, and installing green technologies
25 to reduce energy consumption and provide energy autonomy during extreme events and disasters
26 (https://www.paho.org/en/health-emergencies/smart-hospitals).
27
28 15.6.3 Adaptation Finance and Risk Transfer Mechanisms
29
30 In the majority of small island developing states there is a high dependence on international financing to
31 support adaptation to slow and rapid onset events (Robinson and Dornan, 2017; Petzold and Magnan, 2019).
32 However, funds tend to be geared towards supporting sectoral-level adaptation initiatives for vulnerable
33 natural resource sectors such as water, biodiversity and coastal zones (Kuruppu and Willie, 2015).
34 Considering low income small islands such as Comoros, Haiti, and São Tomé and Príncipe, international
35 modalities do little to address the root causes of vulnerability or to support system-wide transformations
36 (Kuruppu and Willie, 2015). Although countries like Trinidad and Tobago have amassed oil wealth, the
37 profits are not invested in a way that benefits environmental goals (Middelbeek et al., 2014). In Mauritius, a
38 lack of financial resources for climate change adaptation has been recognised as a specific impediment in
39 district council level (Williams et al., 2020).
40
41 Although small island jurisdictions have seen increased flows of adaptation finance through mostly top-town
42 arrangements, they face large implementation difficulties (medium evidence, high agreement) (Weir and
43 Pittock, 2017; Magnan and Duvat, 2018). There are growing concerns among policy- and decision-makers in
44 small islands about the current levels and forms of adaptation finance, and about countries' experience with
45 accessing it (Robinson and Dornan, 2017). In the Caribbean, 38% of flows were concessional loans and 62%
46 were grants (Atteridge et al., 2017); the situation in the Atlantic and Indian Oceans is starkly different--
47 nearly 75% of the flows were in the form of concessional loans and grants accounted for the remaining 25%
48 (Canales et al., 2017). This raises questions about fairness and justice for small islands having to finance
49 adaptation to climate impacts to which they have made a negligible contribution. In the Pacific, 86% of aid
50 was delivered as project-based support (Atteridge and Canales, 2017), that can undermine the long-term
51 sustainability of adaptation interventions (Conway and Mustelin, 2014; Remling and Veitayaki, 2016;
52 Atteridge and Canales, 2017). Direct budget support was rare (Atteridge and Canales, 2017), signalling the
53 importance of works such as Rambarran (2018) that support cross-regional lesson-learning by, for example,
54 showcasing the experience of Seychelles with successfully devising innovative financing mechanisms for
55 supporting adaptation and conservation goals, and reducing its public debt. Regional catastrophe risk
56 insurance schemes however, such as Pacific Catastrophe Risk Insurance Company under the World Bank's
57 Pacific Catastrophe Risk Assessment and Financing Initiative (PCRAFI) Program are trying to enable a
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1 regional effort in increasing accessibility to insurance (PCRAFI, 2017) as does the Caribbean Catastrophe
2 Risk Insurance Facility, although these funds are still rather small compared to the needs across the countries
3 (Handmer and Nalau, 2019).
4
5 Microfinance is increasingly viewed as a positive mechanism to improve access to climate adaptation
6 funding (Di Falco and Sharma, 2018). In the Caribbean, a significant barrier in accessing climate finance
7 relates to bureaucratic structures, which means that money intended for communities does not reach them
8 (Mycoo, 2018a). Many adaptation projects even at the community level have upfront costs that need to be
9 supported, especially in communities where there is little hard cash in use (Remling and Veitayaki, 2016).
10 Despite such challenges, communities in the Pacific region have used "cashless adaptation" for a long time
11 that involves trading of services and items as a form of Indigenous microfinance (Nunn and Kumar, 2019b).
12 Social networks also function as a source of informal microfinance where extended family members send
13 back remittances from overseas to their families and communities especially after disasters. In Samoa
14 Indigenous tourism operators receive remittances from overseas family members (Crichton and Esteban,
15 2018; Parsons et al., 2018), with similar processes observed among atoll communities in the Solomon
16 Islands (Birk and Rasmussen, 2014), Vanuatu (Handmer and Nalau, 2019) and Jamaica (Carby, 2017).
17 However, the role of migration and remittances is still poorly understood; it is difficult to quantify the
18 informal flows and understand the extent they support effective adaptation (limited evidence, high
19 agreement) (Campbell, 2014a; Parsons et al., 2018; Handmer and Nalau, 2019).
20
21 In Old Harbour Bay, Jamaica's largest fishing village, a high number of community members engaged in the
22 fishing industry, particularly vendors and scalers, do not own the material assets needed to fully benefit from
23 these livelihood activities (Baptiste and Kinlocke, 2016). Developing a broader asset portfolio by increasing
24 access to such assets via adaptation finance investments could reduce vulnerability across the community.
25 This could function as an effective livelihood-based adaptation strategy for the most vulnerable such as
26 women, who are part-time employed and in peripheral roles in the fishing industry (Baptiste and Kinlocke,
27 2016). In Belize and the Dominican Republic, many coastal fishers for example use informal credit from
28 food stores or captains to enable them to withstand financial losses that are often incurred during bad
29 weather and extreme events (Karlsson and McLean, 2020).
30
31 In Vanuatu, discussions are ongoing on increasing insurance availability for TCs and droughts, but
32 standardisation of housing designs to get insurance can become difficult where the costs make it prohibitive
33 and run counter to traditional building designs and materials (Baarsch and Kelman, 2016). Empirical
34 evidence from Belize, Grenada, Jamaica and St. Lucia indicates that there are also other factors why people
35 do not take insurance, including "the cost of premiums (44 %), lack of trust in insurance companies (27 %),
36 having never considered insurance (26 %), a lack of need for insurance (25 %) and a lack of knowledge of
37 insurance (22 %)" (Lashley and Warner, 2013, p. 108). Increasing trust could be addressed by seeking out
38 domestic banks or credit unions with whom people are already engaging with, while also using social
39 marketing campaigns to raise awareness of weather-related insurance to address knowledge gaps and lack of
40 awareness of these tools (Lashley and Warner, 2013). In Dominica, many coastal fishers are suspicious of
41 insurance schemes given past experiences of not being paid out on time or having to disclose catch data
42 (Turner et al., 2020). Yet, insurance is not capable of addressing all kinds of loss and damage accruing from
43 climate impacts and should be used as an adaptation strategy in combination with other strategies (Lashley
44 and Warner, 2013).
45
46 Insurance cover is a critical question in small islands. For example, in Vanuatu, some companies do not
47 "cover storm damage from the sea or high tides...which is not helpful for properties damaged by a tropical
48 cyclone's storm surge" (Baarsch and Kelman, 2016)(p. 6). There is also limited access to insurance schemes
49 due to lower demand in small markets (Petzold and Magnan, 2019) especially when many people do not
50 have high cash-based incomes and likely cannot pay insurance premiums (Baarsch and Kelman, 2016). In
51 Saint Lucia and Grenada (via the Caribbean Oceans and Aquaculture Sustainability Facility), discussions are
52 ongoing with regard to national level parametric insurance, underpinned by financing from the US State
53 Department, to help fishing communities recover more quickly following the passage of TCs in the future
54 (Sainsbury et al., 2019; Turner et al., 2020). Likewise, (Reguero et al., 2020) have suggested a resilience
55 insurance mechanism that could in theory reduce climate related losses and damages through investments in
56 nature-based adaptation projects (e.g. coral reef restoration and potentially mangrove restoration).
57
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1 15.6.4 Education and Awareness-Raising
2
3 A significant barrier to effective climate adaptation is the lack of education and awareness around climate
4 change both among the general public, for example in the Bahamas (Petzold et al., 2018) and among
5 decision-makers in the more remote rural communities (Nunn, 2013; Mycoo, 2015). Increasing knowledge
6 on adaptation options and needs can increase adaptive capacity that is underpinned by "the ability of
7 individuals to access, understand and apply the knowledge needed to inform their decision-making
8 processes" (Cvitanovic et al., 2016 p. 54). This should however also be seen as a collective effort (Hayward
9 et al., 2019).
10
11 Workshops and training are seen as crucial at the local scale to build communities' capacity to take action
12 and to integrate climate change considerations to the broader development processes (Remling and
13 Veitayaki, 2016), although purely workshop-based short-term capacity building in adaptation has been
14 questioned (Conway and Mustelin, 2014; Lubell and Niles, 2019). More interactive community engagement
15 strategies could include "participatory three-Dimensional modelling (P3DM), participatory video,
16 development of photo journals, and civil society plans" (Beckford, 2018, p. 46) that enables broader
17 engagement. In Fiji, Laje Rotuma youth EcoCamps have been used to engage younger Fijians to understand
18 adaptation and increasing environmental stewardship with good outcomes (McNaught et al., 2014). In Palau,
19 Camp Ebiil provides a culturally-based platform for younger generations to learn about nature and culture in
20 an interactive camp (Singeo, 2011). Vanuatu's Volunteer Rainfall Observer Network in turn engages
21 volunteers to record their rainfall observations, demonstrating the use of IKLK that can be integrated with
22 contemporary weather forecasting (Chand et al., 2014). Likewise, initiatives such as ePOP Petites Ondes
23 Participatives aim to develop a citizen network to share environmental information (e.g., via minivideos on
24 smartphones). Across the Pacific, projects such as the European Union Pacific Technical Vocational
25 Education and Training on Sustainable Energy and Climate Change Adaptation Project (EU PacTVET),
26 have sought to increase capacity of Pacific islanders in disaster risk management and climate adaptation
27 (Hemstock et al., 2018).
28
29 In Fiji, a study on adaptive behaviour and intention to invest in more adaptive portfolios found that the intent
30 for adaptive behaviour increased with the supply of climate information (Di Falco and Sharma, 2018). In the
31 Pacific, high performing CBA initiatives included climate awareness raising that equipped people with
32 knowledge to understand occurring environmental changes and what to do (McNamara et al., 2020). Lack of
33 information can increase community vulnerability. Remote Indigenous farming communities in St Vincent,
34 in the Caribbean, for example have already observed decreased rainfall and increases in temperatures, but
35 they have been largely excluded from agricultural training that includes information in how to improve
36 agricultural strategies in times of climatic shocks and how to prepare for changing climatic conditions (Smith
37 and Rhiney, 2016). In the Bahamas, cultural background, income and education levels impact the extent that
38 people are aware of climate risks (Petzold et al., 2018) . In Dominica, access to information critical to
39 fisheries is noted as a significant challenge, including data collection, its management and human resources
40 in building capacity to process and use this information for evidence-based decision making (Turner et al.,
41 2020).
42
43 The Caribbean Climate Online Risk and Adaptation tool has been developed to assist the tourism industry in
44 producing "climate-sensitive developments" (Mackay and Spencer, 2017,p. 55). Though some authors
45 conclude on the low climate awareness/understanding among small islanders (Middelbeek et al., 2014;
46 Betzold, 2015; Petzold et al., 2018), others indicate that many Caribbean islanders are acutely aware of past
47 storm events (i.e., social memory) and have a certain degree of self-reliance, which creates the capability to
48 multi-task and cope with limited resources (Petzold and Magnan, 2019). There is, however, a disconnect
49 between knowledge, attitudes and practices--knowledge sharing and learning need to be improved along
50 with the take-up of an evidence-based decision-making approach (Lashley and Warner, 2013; Petzold et al.,
51 2018; Saxena et al., 2018).
52
53 15.6.5 Culture
54
55 Culture can be defined as "material and non-material symbols that express collective meaning" (Adger et al.,
56 2014, p. 762) and includes worldviews and values, how individuals and communities relate to their
57 environment, and what they perceive to be at risk and in need of adaptation (McNaught et al., 2014; Nunn et
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1 al., 2014; Remling and Veitayaki, 2016; Nunn et al., 2017bGranderson, 2017; Neef et al., 2018; Oakes,
2 2019). In small islands, culture plays an important role in individual and community decision-making on
3 adaptation both as an enabling factor and as a barrier (robust evidence, high agreement) (Nunn et al., 2017b;
4 Parsons et al., 2017; Neef et al., 2018; Piggott-McKellar et al., 2020). The concept of Vai Nui as the
5 interconnectedness of Pacific Islanders continues to support the collective agency to plan and undertake
6 adaptation efforts in the region (Hayward et al., 2019). In Samoa, the principles of Fa`asamoa (the Samoan
7 way of life) impacts on how decisions are made, including the role of the aiga (extended family) that is a
8 web of local, national and transnational kinship networks (Parsons et al., 2018). Traditional village council
9 structures and land stewardship enables an expanded range of coastal adaptation options in Samoa, including
10 potential relocation, but at the same time may limit participation of all social groups in adaptation decision
11 making (Crichton et al., 2020). In Dominica, in the aftermath of Hurricane Maria (2017), social capital in the
12 form of transboundary nearby island networks enabled some communities to recover faster from the disaster
13 including access to more livelihood opportunities and assets (Turner et al., 2020).
14
15 Yet, culture is often overlooked in adaptation policies and plans. For example, in the National
16 Communications of 16 SIDS, only one country (Cook Islands) reported adaptation actions that addressed
17 social issues, culture, and heritage (Robinson, 2018b). Externally-driven adaptation efforts in rural small-
18 island communities that exclude community priorities, ignore or undervalue IKLK, and are based on secular
19 western/global worldviews (Donner and Webber, 2014; Prance, 2015; McNamara et al., 2016; Nunn et al.,
20 2017b; Schwebel, 2017; Mallin, 2018; Nunn and McNamara, 2019; Piggott-McKellar et al., 2019b) are often
21 less successful (high agreement, medium evidence). The World Bank Kiribati Adaptation Program (KAP) for
22 example builds mainly on western knowledge and science despite consultations with the Kiribati
23 communities (Prance, 2015). Yet, in many contexts most land and knowledge is embedded in traditional
24 governance and culture while adaptation plans and decisions are made elsewhere on how that land should be
25 used and what knowledge is used (high agreement) (Nunn, 2013; Prance, 2015; Charan et al., 2017; Nalau et
26 al., 2018a; Parsons et al., 2018; McGinn and Solofa, 2020).
27
28 In Kiribati, communities often use different timescales to evaluate the need for adaptation. I-Kiribati
29 culture's core concept of time is short- and medium term (Prance, 2015), which should be considered in
30 adaptation policy and planning processes especially at the household and community level (Donner and
31 Webber, 2014). Key stakeholders, especially community leaders, should be included and empowered to help
32 design and sustain adaptation (Baldacchino, 2018; Weiler et al., 2018). Focusing on values-as-relations (e.g.,
33 island communities' relationship with the environment and each other) could diversify the values considered
34 in adaptation decision-making processes (Parsons and Nalau, 2019). Indeed, those Pacific islands with a
35 more island-centric approach to climate adaptation tend to have overall more successful adaptation policies
36 in place (Schwebel, 2017).
37
38 The cultural context and sources of knowledge are myriad and diverse in small islands. Community
39 members often use both IKLK as well as western scientific-based weather forecasts to take actions to
40 prepare for extreme weather events (Chand et al., 2014; Johnston, 2015; Janif et al., 2016; Granderson, 2017;
41 Kelman et al., 2017), with specific examples from Niue, Tonga, Vanuatu and the Solomon Islands (high
42 agreement, high evidence) (Chand et al., 2014; Chambers et al., 2017; Chambers et al., 2019). In Samoa,
43 people keep particular areas reserved for disaster times such as TC seasons (Kuruppu and Willie, 2015)
44 while in Vanuatu IKLK indicators for tropical cyclones include mango trees flowering early and turtles
45 going further inland to lay their eggs (Chand et al., 2014). IKLK are however not evenly distributed within
46 communities due to IKLK being traditional intellectual property of particular roles in the villages (e.g.,
47 weathermen in Vanuatu), and not available to other community members or external actors directly (Chand
48 et al., 2014; Prance, 2015). In Tongoa Island, Vanuatu, communities are finding however that their IKLK-
49 based seasonal calendars are out of sync given the changes in climatic conditions (Granderson, 2017) while
50 erosion of IKLK remains a concern across most small island nations (Kuruppu and Willie, 2015;
51 Granderson, 2017; Beckford, 2018).
52
53 Not all IKLK and other knowledge are necessarily helpful and IKLK can lead to maladaptation (Mercer et
54 al., 2012; Beckford, 2018). Elders from the Chuuk State (Federated States of Micronesia, (Elders from Atafu
55 Atoll, 2012), for instance, assign blame for changeable weather patterns, destructive typhoons, and loss of
56 biodiversity to people's failure to maintain and employ their IKLK. Fatalism (belief that disasters are God's
57 will) is still reported as a major cultural barrier to adaptation. In Maldives fatalism decreases direct
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1 adaptation action and influences perceptions of climate risks (Shakeela and Becken, 2015) while Indigenous
2 communities in St Vincent do not prepare for hurricanes or climatic shocks for the same reason (Smith and
3 Rhiney, 2016). In Oceania, Christianity and the church play an important role in how issues, such as climate
4 change, are communicated and thought about (Rubow and Bird, 2016; Nunn et al., 2017b), including the
5 Noah and flood story used as a justification that there is no need to worry about sea level rise (Rubow and
6 Bird, 2016). New emerging forms of eco-theology (theology that connects humans with land, sea and sky)
7 however situate climate change as part of environmental stewardship (Rubow and Bird, 2016) making
8 churches active partners in caring for the environment.
9
10 Many studies also now demonstrate the value in considering multiple systems of knowledge through
11 collaborative and co-production projects and strategies, which allow for culturally-situated knowledge,
12 values, and practices to be positioned at the heart of sustainable climate change adaptation (high agreement)
13 (Chambers et al., 2017; Plotz et al., 2017; Beckford, 2018; Malsale et al., 2018; Parsons et al., 2018; Suliman
14 et al., 2019). In the Caribbean context, Beckford (2018) suggests the establishment of Caribbean Local and
15 Traditional Knowledge Network, a shared regional platform makes IKLK more available for climate
16 adaptation and community resilience projects where appropriate. Likewise, Indigenous research
17 methodologies are emerging that introduce more culturally grounded concepts and methods into how
18 research is conducted and decolonise mainstream research in the Pacific Islands (Suaalii-Sauni and Fulu-
19 Aiolupotea, 2014).
20
21 Despite widespread international evidence that the impacts of climate change and disaster events often
22 negatively affect women (and gender minorities) more than men (McSherry et al., 2014; Aipira et al., 2017;
23 Gaillard et al., 2017), attention to gender equality as a concept is still only "embryonic in climate change
24 adaptation in the Pacific" and although recognised in some policies and project designs, it is not well
25 supported by on-the-ground actions or well monitored (Aipira et al., 2017, p. 237). Many Pacific small island
26 climate change adaptation policies do not mainstream gender across the activities (Aipira et al., 2017), with
27 women's groups being excluded from climate grants due to patriarchal formal and informal governance
28 structures, lack of resources, lower access to educational and training schemes, and no track record (or
29 receiving grants or meeting grant milestones) (McLeod et al., 2018). However, Pacific women identify
30 several strategies that enable them to adapt to climate change more effectively. These include the recognition
31 and support of women's IKLK by governments, researchers, and NGOs; increasing women's access to
32 climate change funding and support from organisations to allow them to meet the requirements of
33 international climate change grants; and specific education and training to women's groups to allow them to
34 develop strategic action plans, mission statements, learn financial reporting requirements, as well as general
35 leadership and institutional training (McLeod et al., 2018). Such and other measures could enable a broader
36 representation and participation in adaptation processes despite cultural constraints (Table 15.7 on Enabling
37 Conditions).
38
39
40 Table 15.7: Enabling Conditions and Factors for Adaptation in Small Islands
41 [INSERT TABLE 15.7 HERE]
42
43
44 15.7 Climate Resilient Development Pathways and Future Solutions in Small Islands
45
46 Synergies exist between climate resilient development pathways and implementation of SDGs in small
47 islands because development decisions and outcomes are strengthened by consideration of climate and
48 disaster risk (Robinson, 2017b; Hay et al., 2019a). However, monitoring progress of SDGs is challenging for
49 small islands, in part due to large numbers of indicators and inadequate data. Literature on SDG
50 implementation is generally lacking for small islands as is the integration of climate risk into infrastructure
51 decisions.
52
53 Decisions that are optimal for adaptation may not be acceptable in the wider development context within
54 which they operate. In the Pacific region, where 67% of infrastructure is located within 500 metres of
55 coastline and commercial, public and industrial infrastructure are particularly vulnerable due to the location
56 of urban centres (Kumar and Taylor, 2015). Yet the Parliamentary Complex in Samoa was redeveloped at
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1 the original site due to cultural and historical factors despite strong evidence of the need to relocate (Hay et
2 al., 2019b).
3
4 Energy transitions in the Pacific islands demonstrate development synergies such as reduced dependency on
5 volatile fossil fuel markets, increased resilience to weather related disasters and less need for investment in
6 large scale centralised energy systems (Dornan, 2014; Cole and Banks, 2017; Weir, 2018; Weir and Kumar,
7 2020). However, high and rapid energy transition ambitions can lead to trade offs for rural electrification
8 (Box 18.4; Dornan, 2014; Cole and Banks, 2017; Hills et al., 2018).
9
10 Tourism system transitions can enable the sector to contribute to climate resilient development pathways
11 through managing climate risks and improving ecological, economic and social outcomes for small islands
12 (medium evidence, high agreement) (Loehr, 2019; Mahadew and Appadoo, 2019; Loehr et al., 2020; Sheller,
13 2020).
14
15 There is a clear role for local governments to work closely with the informal private sector to achieve a
16 'trifecta' of climate change adaptation, economic development and disaster risk reduction, especially for
17 women (McNamara et al., 2020). Yet, many cities and local governments in the Pacific region are severely
18 resource constrained (Kelman, 2014; Kiddle et al., 2017; Keen and Connell, 2019; Nunn and McNamara,
19 2019).
20
21 Broader innovation in climate resilient development policy making has taken place in the Pacific (Hay et al.,
22 2019a) and Caribbean (Mycoo, 2018a). The Pacific region is bringing together disaster risk management,
23 low carbon growth and climate change adaptation with broader development efforts for the first time (SPC,
24 2016). Improvements in cross sectoral and cross agency coordination are creating opportunities for improved
25 disaster preparedness and resilience measures in small islands (Webb et al., 2015; Nalau et al., 2016).
26 Further integration between development priorities and risk management in national budgetary and
27 development processes is necessary, as is continued investment in coordination mechanisms (Hay et al.,
28 2019a).
29
30 Early research on the response to COVID-19 indicates that existing disaster response mechanisms in the
31 Caribbean islands have assisted in rapid responses to COVID-19 (Hambleton et al., 2020). Many small
32 islands are highly dependent on tourism for their economies and are facing worsening crises associated with
33 climate-related disasters and more recently COVID-19 disruptions of travel (Sheller, 2020). The adaptive
34 capacity and innovations demonstrated by SIDS during COVID-19, moving beyond dependence on
35 `extractive' international tourism, demonstrate the potential benefits of diversified and sustainable
36 economies (and ecologies) for the enhanced resilience of both human and ecological communities (Sheller,
37 2020).
38
39 In the context of small islands, climate justice research is expanding beyond initial debates about nation-
40 states responsibilities for the causes and responses to climate change, to demonstrate complex and dynamic
41 intergenerational and multiscalar dilemmas of climate justice (Ferdinand, 2018; Sheller, 2018; Baptiste and
42 Devonish, 2019; Look et al., 2019; Douglass and Cooper, 2020; Kotsinas, 2020; Sheller, 2020). In Caribbean
43 SIDS, research highlights how intersecting external and internal socio-economic and political processes are
44 allowing marginalised populations to become increasingly socially and economically disadvantaged and
45 politically marginalised, which in turn heightens climate vulnerability and impedes sustainable development
46 efforts (Baptiste and Devonish, 2019) (Moulton and Machado, 2019; Gahman and Thongs, 2020; Rhiney,
47 2020; Duvat et al., 2021b). Inequity extends to how development and disaster aid were coordinated and
48 distributed within various nations after Hurricanes Irma, Maria and Harvey in 2017.
49
50
51 15.8 Research Gaps
52
53 Despite intensive study many knowledge gaps remain due to the complexity of biophysical and social
54 interactions, and the local and regional diversity of small islands. Research and data gaps exist in four areas:
55 island-scale data availability; ecosystem services data; vulnerability and resilience, and adaptation (Table
56 15.8).
57
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1
2 Table 15.8: Research Gaps in Small Islands
3 [INSERT TABLE 15.8 HERE]
4
5
6 [START FAQ15.1 HERE]
7
8 FAQ 15.1: How is climate change affecting nature and human life on small islands, and will further
9 climate change result in some small islands becoming uninhabitable for humans in the near
10 future?
11
12 Climate change has already affected and will increasingly affect biodiversity, nature's benefits for people,
13 settlements, infrastructure, livelihoods and economies on small islands. In the absence of ambitious human
14 intervention to reduce emissions, climate change impacts are likely to make some small islands
15 uninhabitable in the second part of the 21st century. By protecting and restoring nature in and around small
16 islands as well as implementing anticipatory adaptation responses, humans can help reduce future risks to
17 ecosystems and human lives on most small islands.
18
19 Observed changes including increases in air and ocean temperatures, increases in storm surges, heavy
20 rainfall events, and possibly more intense tropical cyclones - are already reducing the number and quality of
21 ecosystem services, thereby causing the disruption of human livelihoods, damage to buildings and
22 infrastructure, and loss of economic activities and cultural heritage on small islands. Widespread observed
23 impacts include severe coral reef bleaching events, such as that associated with the 201516 El Niño season,
24 the most damaging on record worldwide. Additionally, the 2017 Atlantic hurricane season was unusually
25 characterised by sequential severe tropical cyclones that resulted in widespread cyclone-induced damage to
26 ecosystems from the very interior of small islands to those of the ocean waters that surround them as well as
27 damage to human settlements and economic activities within the whole Caribbean region. Although
28 knowledge is limited regarding long term increases in tropical cyclone intensity, studies have shown that
29 heavy rainfall and intense wind speed of individual tropical cyclones were increased by climate change. The
30 combination of various climate events, such as tropical cyclones, extreme ocean waves, and El Niño or La
31 Niña phases, with sea-level rise causes increased coastal flooding, especially on low-lying atoll islands of the
32 Indian and Pacific Oceans.
33
34 The expected increased risk of such impacts under further climate change is significant. For example, some
35 low-lying islands and areas may be extensively flooded at every high tide or during storms. As a result, their
36 freshwater supplies and soils would be repeatedly contaminated by saltwater, with adverse cascading
37 consequences for freshwater and terrestrial food supplies, biodiversity and ecosystems, and economic
38 activities. It is unlikely that these locations would remain habitable unless such impacts are mitigated
39 through reduction of heat-trapping greenhouse gas emissions or adaptation solutions that are acceptable for
40 the populations of these islands. Acceptable adaptation options may be limited in these locations.
41 Additionally, drought intensity may challenge freshwater security in some regions such as the Caribbean.
42 Likewise, remote atoll islands where inhabitants rely on reef-derived food and other resources and that are at
43 high risk of widespread coral reef degradation may become uninhabitable. Strategies to reduce risk may
44 include substituting the consumption of vulnerable inshore reef resources by developing onshore aquaculture
45 (fish farming), or promoting access to tuna and other pelagic fish, and/or importing food to meet nutritional
46 needs. However, adoption of these strategies will depend on the acceptance of their local populations.
47
48 The intensity and timing of such impacts will be more severe under high warming futures compared to low
49 warming futures accompanied by ambitious adaptation. Tailored, desirable and locally owned adaptation
50 responses that incorporate both short- and long-term time horizons would certainly help to reduce future
51 risks to nature and human life in small islands. Among the short-term measures frequently employed to
52 address sea-level rise and flooding are seawalls. Long-term measures include ecosystem-based adaptation
53 such as mangrove replanting, relocation of coastal villages to upland sites, creation of elevated land through
54 reclamation, revised building codes as part of a broader disaster risk reduction strategy, shifting to alternative
55 livelihoods and changes in farming and fishing practices.
56
57 [END FAQ15.1 HERE]
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1
2
3 [START FAQ15.2 HERE]
4
5 FAQ 15.2: How have some small-island communities already adapted to climate change?
6
7 Faced with rising sea levels and storm surges along their coastal areas which have significantly threatened
8 people's safety, buildings, infrastructure and livelihoods, Small Island communities have already embarked
9 on the use of different adaptation strategies. These include reactive adaptation, which deals with short-term
10 measures, and anticipatory adaptation, which takes action in advance to lessen climate change impacts in
11 the long run. Reactive measures have proven not always to be effective. In contrast, anticipatory measures
12 hold much promise for future adaptation.
13
14 The majority of people living on small islands occupy coasts, so the most widespread threats to people's
15 livelihoods are those from sea-level rise, shoreline erosion, increased lowland flooding, and salinization of
16 groundwater and soil. Humans can either adapt reactively or anticipate coming changes and prepare for
17 them. Given the diversity of small islands across the world, and their capacities to adapt, there is no single
18 solution that fits all contexts.
19
20 Coastal livelihoods in particular are already impacted by climate impacts. Coastal fishers have adapted to
21 these changes in environmental conditions by diversifying livelihoods, expanding aquaculture production,
22 considering weather insurance, building social networks to cope with reduced catches and availability during
23 extreme storms, switching fishing grounds, and changing target species. Similarly, farmers have diversified
24 livelihoods to more cash- and service-based activities such as tourism, changed plant species that thrive
25 better in altered conditions, and shifted planting seasons according to changes in climate.
26
27 A typical reactive adaptation along small-island coasts involves the construction of hard impermeable
28 structures such as seawalls to stop the encroachment of the sea. Yet such structures, especially along rural
29 island coasts, often fail to prevent flooding during extreme sea levels or extreme-wave impacts, and can
30 inadvertently damage nearshore ecosystems such as mangroves and beaches. In the Caribbean, Indian Ocean
31 islands and some Pacific islands, there are numerous examples of coastal engineering structures that have
32 been destroyed already or are in grave danger from the encroaching sea. In many instances, citizens and
33 governments are unable to access external advice or funding, communities have built such structures without
34 assistance or knowledge of expected future sea level rise.
35
36 In contrast, anticipatory adaptation, which anticipates expected future impacts and acts in advance, requires a
37 longer-term view as well as some understanding of future climate-change impacts in particular contexts.
38 Along small-island coasts, anticipatory adaptation typically involves recognising that sea level will continue
39 rising and that problems currently experienced will be amplified in the future. One strategy for anticipatory
40 adaptation in response to sea level rise and flooding is relocation, which is the movement of coastal
41 communities away from vulnerable (coastal-fringe) locations to sites that are further inland. . Coastal setback
42 policies have been applied to hotels in some islands such as Barbados. In coastal locations where the risks of
43 rising sea level, flooding and erosion are very high and cannot effectively be reduced, `retreat' from the
44 shoreline is the only way to eliminate or reduce such risks.
45
46 Where relocation is successful, it is most commonly driven and funded by governments and non-government
47 organisations, often within a specially designed policy framework. The Government of Fiji, for example, has
48 introduced a relocation framework that specifically develops guidance on relocation processes, with several
49 villages already having relocated. Evaluations to date recommend thorough cost-benefit analyses of
50 relocation be undertaken before this strategy is pursued. Relocation is often viewed as a `last resort'
51 adaptation option because of high cost and because some socio-cultural aspects of life cannot be maintained
52 in locations separated from customary land. The Bahamas relocated a community on Family Island from the
53 shoreline to an inland location and the community of Boca de Cachón in the Dominican Republic was
54 relocated to higher ground. The Navunievu community (Bua, Fiji) has mandated that every young adult
55 building their family home in the village should do so upslope rather than on the regularly flooded coastal
56 flat where the existing village is located. Over the next few decades, this will result in the gradual upslope
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1 migration of the community, an example of autonomous adaptation. Such creative community-grounded
2 solutions hold great promise for future adaptation on small islands, where they are undertaken inclusively.
3
4 Anticipatory adaptation has been aligned with disaster risk reduction in some small islands. For example,
5 Jamaica adopted such an approach in relocating three communities. Recognising that a proactive approach is
6 needed, Jamaica developed a Resettlement Policy Framework aligned with the National Development Plan
7 and based on vulnerability assessments of communities at risk of climate change and disaster risk. A
8 resettlement action plan was developed for the Harbour Heights community using community engagement to
9 design successful planned relocation. In some islands revised building codes are implemented as an
10 anticipatory adaptation measure. As part of the build-back-better strategy hurricane resistant roofs are being
11 built to cope with strong winds associated with tropical cyclones.
12
13 Ecosystem-based adaptation can be a low-cost anticipatory adaptation measure that is often used in small
14 islands. It is referred to as a `no-regret' or `low-regret' strategy because it is low-costing, brings co-benefits
15 and requires less maintenance in contrast to hard engineering structures. Ecosystem-based adaptation is used
16 at different scales and in different sectors such as to protect fisheries, farming and tourism assets, and
17 integrates various stakeholders from national to local governments and non-governmental agencies. Many
18 islands have implemented ecosystem-based adaptation such as watershed management, mangrove replanting
19 and other nature-based solutions to strengthen coastal foreshore areas that are subjected to coastal erosion
20 and flooding caused by sea level rise and changing rainfall patterns. For example, mangroves have been
21 planted on several cays in Belize and pandanus trees have been planted near the coastlines of the Marshall
22 Islands. Agroforestry is another example of ecosystem-based adaptation. Planting trees and shrubs in
23 combination with crops has been used to increase resilience of crops to droughts or excessive rainfall run-
24 off. Case studies show that people living on islands benefit even further from using ecosystem-based
25 adaptation. Their health improves as well as their food and water supply, while risks of disasters caused by
26 extreme events are reduced.
27
28
29 15-55 Total pages: 107
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1 Figure FAQ15.2.1: Adaptation options for rural coastal communities in small islands
2 A In many places today, coastal communities which have been established for hundreds of years are being more
3 regularly inundated than ever before as a result of rising sea level. B By the end of this century, sea level in such
4 places may have risen one meter or more, making many such settlements (largely) uninhabitable, underscoring the need
5 for effective (anticipatory) adaptation. C One option is in-situ adaptation, popular because it is cheaper and less
6 disruptive than other options; it is typically characterised by mangrove replanting, seawall construction and raising of
7 dwellings. D A second option is for communities to incrementally relocate upslope by building all new houses further
8 inland. E A third option is complete relocation of a vulnerable coastal community with external support upslope and
9 inland.
10
11 [END FAQ15.2 HERE]
12
13
14 [START FAQ15.3 HERE]
15
16 FAQ 15.3: How will climate related changes affect the contributions of agriculture and fisheries to
17 food security in small islands?
18
19 Agriculture and fisheries are heavily influenced by climate, which means a change in occurrence of tropical
20 cyclones, air temperature, ocean temperature and/or rainfall can have considerable impacts on the
21 production and availability of crops and seafood and therefore the health and welfare of island inhabitants.
22 Projected impacts of climate change on agriculture and fisheries in some cases will enhance productivity,
23 but in many cases could undermine food production, greatly exacerbating food insecurity challenges for
24 human populations in small islands (also see Cross-Chapter Box MOVING PLATE in Chapter 5).
25
26 Small islands mostly depend on rain-fed agriculture, which is likely to be affected in various ways by
27 climate change, including loss of agricultural land through floods and droughts, and contamination of
28 freshwater and soil through salt-water intrusion, warming temperatures leading to stresses of crops, and
29 extreme events such as cyclones. In some islands, crops that have been traditionally part of people's diet can
30 no longer be cultivated due to such changes. For example, severe rainfall during planting seasons can
31 damage seedlings, reduce growth and provide conditions that promote plant pests and diseases.
32
33 Changes in the frequency and severity of tropical cyclones or droughts will pose challenges for many
34 islands. For example, more pronounced dry seasons, warmer temperatures, greater evaporation could cause
35 plant stress reducing productivity and harvests. The impacts of drought may hinder insects and animals from
36 pollinating crops, trees and other vegetative food sources on tropical islands. For instance, many agroforestry
37 crops are completely dependent on insect pollination, and it is, therefore, important to monitor and recognize
38 how climate change is affecting the number and productivity of these insects. Coastal agroforest systems in
39 small islands are important to national food security but rely on biodiversity (e.g., insects for pollination
40 services). Biodiversity loss from traditional agroecosystems has been identified as one of the most serious
41 threats to food and livelihood security in islands. Ecosystem-based adaptation practices and diversification of
42 crop varieties are possible solutions.
43
44 The continuous reduction of soil fertility as well as increasing incidences of pests, diseases, and invasive
45 species contribute to the growing vulnerability of the agricultural systems on small islands. Higher
46 temperatures could increase the presence of food or water borne diseases and the challenge of managing
47 food safety. Changes in weather patterns can also disrupt food transportation and distribution systems on
48 islands where indigenous communities are often located in remote areas.
49
50 Impacts of climate change on fisheries in small islands result from ocean temperature change, sea-level rise,
51 extreme weather patterns such as cyclones, reducing ocean oxygen concentrations and ocean acidification.
52 These combined pressures are leading to the widespread loss or damage to marine
53 habitats such as coral reefs but also mangroves and seagrass beds and consequently of important fish species
54 that depend on these habitats and are crucial both to the food security (a high proportion of dietary protein is
55 derived from seafood) and incomes of island communities. Shifting ocean currents and warming waters are
56 also changing the distribution of pelagic fish stocks, especially of open-water tuna, with further
57 consequences for both local food security and national economies, where they are often highly dependent on
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1 income from fishing licenses (e.g., 98% of Gross Domestic Product in Tokelau, 66% of national income in
2 Kiribati).
3
4 Climate change is projected to have profound effects on the future status and distribution of coastal and
5 oceanic habitats, and consequently of the fish and invertebrates they support. High water temperature causes
6 changes in the growth rate of fish species as well as the timing of spawning and migration patterns, with
7 consequences for fisheries catch potential. Some small island countries and territories are projected to
8 experience more than 50% declines in fishery catches by 2100. Other small islands such as Easter Island
9 (Chile), Pitcairn Islands (UK), Bermuda, and Cabo Verde may actually witness increases in catch potential
10 under certain climate scenarios. Food shortages are often apparent in small islands, following the passage of
11 catastrophic tropical cyclones. Access to pelagic fisheries can help to alleviate immediate food insecurity
12 pressures in some circumstances, whereas aquaculture (fish farming) is being viewed as a longer term means
13 of diversifying incomes and enhancing resilience in many Caribbean and Pacific islands.
14
15 [END FAQ15.3 HERE]
16
17
18
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1 Large Tables
2
3 Table 15.2: A small subset of projected changes in basic climate metric. Med=Mediterranean; NC=no change
General Metric Specific Specific Comments Reference
Phenomenon Location projections projections
2040-2060 2080-2100
Trend
RCP RCP RCP RCP
4.5 8.5 4.5 8.5
Bowden
Hotter, Monthly mean Specific to et al.
Caribbean especially in temperature
1.2C 1.6C 3.0C
the East compared to 1971-
2000 NA Lesser (2020)
rise rise rise
Antilles Cantet et
al. (2014)
Low-
Average annual
confidence,
East temperature 1.5-2C 2.5C Chou et
Atlantic
Hotter NA NA specific to
compared to 1971- rise rise al. (2020)
Sao Tome
2000
and Principe
Average maximum
Air Hotter, daily temperature 1.6- Specific to Varotsos
2-2.5C
Temperature Med especially in during summer 1.9C NA NA Sicily, Crete et al.
rise
summer compared to 1970- rise and Cyprus (2021)
2000
Average temperature 0.5- 1.0- 1.0- 2.0- Consistent
Lough et
Pacific Hotter compared to 1986- 1.5C 2.0C 2.0C 4.0C in tropical
al. (2016)
2005 rise rise rise rise lattitudes
Global Hotter Heat index compared 1C Equatorial,
small to 1986-2005 rise coastal and
islands 1.5C 1.3C 2.8C continental Harter et
rise rise rise islands al. (2015)
hotter than
oceanic
100%
more High natural
El variability
More Cai et al.,
Ninos, limits
frequent Frequency compared (2014);
NA NA NA 73- statistical
extreme to ~1900-1999 Cai et al.
100% significance
events (2015b)
more in related
ENSO Pacific La patterns
Ninas
Inconclusive Amplitude change 0.02C 0.01C 0.04C 0.04C Specific Cai et al.,
change in compared to 1979- drop rise drop rise projections (2018);
variability 2005 are not Beobide-
statistically Arsuaga
significant et al.
(2021)
Slightly Total rainfall 5% 8%
Significant
East wetter, more compared to wet/dry rise/ rise/ Cantet et
NA NA local
Caribbean extreme season compared to 10% 15% al. (2014)
variability
seasonality 1971-2001 drop drop
Precipitation Stennett-
West/
North Drier Annual rainfall Up to Specific to
Caribbean
Brown et
compared to 1986- 9% 327% Puerto Rico
al. (2017);
2005; consecutive dry NA less NA more and US
Bowden
days compared to rain dry Virgin
et al.
1961-1990 days Islands
(2020)
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Low-
Monthly rainfall 10- 10- confidence,
East Inconclusive Chou et
compared to 1971- 25mm 25mm NA NA specific to
Atlantic change al. (2020)
2000 rise drop Sao Tome
and Principe
Wetter, Low-
confidence, Sa'adi et
Annual average specific to al. (2017)
Borneo
West especially 2% 6% 3% 8%
Pacific
rainfall compared to
after mid- rise rise rise rise
1971-2005
century
Central Drier, more Total rainfall Low-
Pacific extreme compared to 1975- 15% 20% 17% 30% confidence, Timm et
seasonality 2005 drop drop drop drop specific to al. (2015)
Hawaii
Drier during 0.2
Average change in
Southwest the wet mm Lazenby
daily rainfall Low
Indian season, NA NA NA per et al.
compared to 1971- confidence
Ocean especially day (2018)
2000
south of 10S drop
Specific to
Annual mean 70- Malta; no
Drier, but 60-150 Varotsos
precipitation 100 significant
Med highly mm NA NA et al.
compared to 1960- mm change in
varied drop (2021)
1990 drop Sicily, Crete
and Cyprus
Confidence
Global Slightly Mean annual limited by
small wetter, precipitation
islands highly compared to 1986- <1% <1% 1.8% 3.2% Harter et
variable 2005
high
rise rise rise rise al. (2015)
standard
deviation
30-
More storms 60% Specific to
North in the west, Frequency compared rise/ Arabian sea/ Bell et al.
Indian
Ocean NA NA NA
fewer in the to 1990-2013 20- Bay of (2020)
east 40% Bengal
drop
Fewer 20-
South storms, Storm/category 4-5 40%
Indian
Ocean fewer strong frequency compared NA NA NA drop/ Bell et al.
(2019a)
storms in to 1979-2010 0-20%
east drop
Slightly Storm density
more and compared to 1970-
15- Kossin et
stronger 2000; poleward shift
Tropical Northwest 40% 10-40N, al. (2016);
storms at NA NA NA
in annual mean of
Cyclones Pacific increasingly location of maximum rise; 140-170E Chand et
0.2° al. (2019)
high intensity compared to
latitudes 1980-2005
0-20%
Southwest South/North Bell et al.
Less
Storm density drop/
and low-
frequent Pacific up to (2019a)
latitude compared to 1970- NA NA NA 20-
storms
20N, 100- Chand et
Pacific
2000 30%
140E al. (2019)
drop
Less Storm frequency No data for
Northeast
2-13% Bell et al.
frequent
Pacific compared to 1970- NA NA NA Southern
storms drop (2019b)
2016 Hemisphere
Central More and Mean annual 31%/ Yoshida
North stronger TC/category 4-5
Pacific storms composition Specific to
NA NA NA 88% et al.
Hawaii
rise (2017)
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compared to 1979-
2010
Minor/major cyclones 12% Specific to
Slightly Cantet et
Caribbean compared to 1984- NA drop/ NA NA lesser
fewer storms al. (2021)
2013 NC Antilles
More storms
and slightly
Storms per decade Specific to Yoshida
East more 0-3
compared to 1979- NA NA NA latitude et al.
Atlantic frequent rise
2010 >15N (2017)
intense
storms
Decreased
frequency Frequency of storms González-
Alemán et
Extratropical 12% al. (2019)
Med
but compared to 1986- NC NA NA
cyclone
drop
increased 2005
intensity
1
2
3 Table 15.3: Percentage of selected islands classified as refugia for biodiversity at increasing levels of warming. While
4 protected land is still `protected' this table demonstrates the difficulty of protecting lands which might be `more
5 resilient' to climate change under increasing levels of warming and current land use practices. Derived from current and
6 future projected distributions of ~130,000 terrestrial fungi, plants, invertebrates and vertebrates (Warren et al., 2018a).
7 Refugia =areas remaining climatically suitable for >75% of the species modelled (Warren et al., 2018b). Projections:
8 based on mean impacts from 21 CMIP5 climate model patterns (no dispersal) and elevationally downscaled to 1km
9 under interpolated warming levels derived from RCP 2.6, 4.5, 6.0 and 8.0 (Warren et al., 2018a). First column-set = %
10 island/island chain classified as a refugia based on climate alone ; second column-set = % natural land projected to be
11 climate refugia -- illustrating potential refugia `space' already lost to habitat conversion. Colour Key: white > 50%;
12 yellow = 30%-50%; red = 17%-30% and dark red <17% of land classified as refugia.
Island(s) Climate °C Climate + Land Use °C
0.5 1 1.5 2 2.5 3 3.5 4 0.5 1 1.5 2 2.5 3 3.5 4
Aegean Islands 98 89 85 68 39 19 12 6 66 62 60 50 32 16 11 6
American Samoa 100 100 100 100 83 52 39 25 39 39 39 39 34 24 18 11
Andaman Nicobar 100 95 90 46 7 2 1 0 92 88 84 45 7 2 1 0
Balearic Islands 99 97 95 82 26 6 4 2 29 28 28 25 13 6 3 2
Bangka 100 100 97 3 1 0 0 0 20 20 19 1 0 0 0 0
Barbados 94 67 53 25 5 0 0 0 10 7 6 3 1 0 0 0
Borneo 98 92 89 60 25 14 10 6 67 62 60 43 24 13 10 6
Bougainville 92 81 77 62 39 28 24 19 87 77 74 58 37 27 23 18
British Indian Ocean
100 100 94 0 0 0 0 0 47 47 47 0 0 0 0 0
Territory
Corsica 72 61 57 43 29 18 15 10 64 53 50 38 26 16 13 8
Crete 91 83 80 68 52 35 27 20 51 47 46 42 35 26 22 17
Cuba 97 94 92 69 14 4 3 1 48 46 45 36 10 4 3 1
Cyprus 53 51 49 44 32 20 14 8 48 46 44 37 24 14 9 6
Dominica 79 66 63 51 41 28 20 14 79 66 63 51 41 28 20 14
French Polynesia 100 100 100 100 100 81 68 54 38 38 38 38 38 32 28 23
Galapagos 91 82 79 67 50 27 18 13 93 88 86 74 54 33 21 14
Grenada 73 49 43 29 18 10 6 3 71 48 43 29 18 10 6 3
Guadeloupe 91 71 64 27 19 13 9 6 57 46 42 26 19 13 9 6
Guernsey 100 52 41 0 0 0 0 0 13 7 5 0 0 0 0 0
Hispaniola 77 60 54 35 22 15 12 9 55 43 40 28 19 13 11 8
Indonesia 95 87 81 54 28 17 14 11 60 55 51 36 23 15 12 10
Jamaica 77 65 61 47 31 17 10 5 64 54 51 40 27 15 9 4
Java 91 74 65 37 24 17 13 10 27 24 22 18 14 11 9 7
Kiribati 100 55 38 14 0 0 0 0 15 12 12 5 0 0 0 0
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Madagascar 98 90 87 70 47 28 22 13 84 77 73 58 37 21 16 10
Maldives 100 38 1 0 0 0 0 0 16 0 0 0 0 0 0 0
Marajo 100 58 33 0 0 0 0 0 91 55 33 0 0 0 0 0
Marshall Islands 100 99 99 55 22 0 0 0 46 46 46 15 10 0 0 0
Mauritius 100 100 100 100 100 100 92 74 27 27 27 27 27 27 25 23
Micronesia 100 100 100 78 59 31 16 6 86 86 86 72 56 29 15 6
Montserrat 61 43 39 27 20 9 9 4 56 38 35 23 17 9 7 4
Nauru 100 100 97 0 0 0 0 0 11 11 11 0 0 0 0 0
New Caledonia 100 100 99 97 89 62 45 31 76 75 75 74 69 53 41 28
New Guinea 95 84 73 47 32 25 22 19 86 76 67 43 30 23 21 18
Northern Mariana
100 100 99 95 58 29 19 11 49 49 49 46 35 22 16 9
Islands
Orinoco Delta 100 31 9 0 0 0 0 0 93 29 9 0 0 0 0 0
Palau 100 79 73 21 0 0 0 0 74 59 55 17 0 0 0 0
Palawan 86 70 64 36 21 12 9 6 55 47 44 31 20 12 9 6
Philippines 90 74 66 41 27 16 12 8 34 30 28 21 15 10 8 6
Prince Edward 100 100 100 100 100 97 9 0 35 35 35 35 35 33 2 0
Puerto Rico 84 66 59 41 25 15 11 7 63 52 49 36 24 14 11 7
Saint Lucia 77 50 45 29 14 6 3 1 72 50 45 29 14 6 3 1
Saint Vincent & the
73 57 50 37 27 18 13 8 63 50 44 34 23 15 10 5
Grenadines
Samoa 100 100 100 99 89 67 56 46 34 34 34 34 31 24 22 20
Sardinia 95 87 83 65 34 16 10 5 41 38 37 31 22 12 8 4
Seychelles 100 100 98 83 57 25 16 9 25 25 25 22 18 8 6 5
Sicily 93 84 80 60 35 18 11 7 16 15 15 13 10 7 6 4
Singapore 100 100 100 98 9 0 0 0 14 14 14 13 3 0 0 0
Solomon Islands 93 79 74 48 28 15 10 6 92 78 73 48 28 15 10 6
Sri Lanka 98 94 89 64 23 11 7 5 47 46 44 36 16 7 5 4
Sulawesi 86 75 71 58 44 33 28 23 60 54 52 46 38 30 26 21
Sumatra 96 90 87 65 24 16 13 11 40 37 36 30 18 13 11 9
Sumba 98 90 86 70 49 23 11 4 36 33 31 26 18 9 4 2
Timor 92 84 80 66 48 30 22 15 11 10 9 8 7 5 4 3
Trinidad and 88 24 16 6 3 1 0 0 64 20 14 6 3 1 0 0
Tobago
Tuvalu 100 100 100 34 0 0 0 0 3 3 3 0 0 0 0 0
Wallis and Futuna 100 100 100 65 32 11 3 0 35 35 35 33 21 7 1 0
1
2
3 Table 15.5: Summary of inter- and intra-regional transboundary risks and impacts on small islands
Transboundary Small Island examples Reference
Risks/Issues
Large ocean waves from Unusually large deep ocean swells generated from sources Hoeke et al. (2013);
distant sources in the mid and high latitudes by extratropical cyclones Smithers and Hoeke
(ETCs) cause considerable damage on the coasts of small (2014); Shope et al.
islands thousands of kilometres away in the tropics. (2016); Canavesio
Impacts include inundation of settlements, infrastructure, (2019); Wandres et al.
and tourism facilities as well as coastal erosion. These (2020)
waves can propagate to and influence reef islands in
equatorial areas not usually exposed to high energy Jury (2018)
waves.
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Examples of extratropical swell waves causing flooding
and inundation have been reported throughout the Pacific
(French Polynesia, Fiji, Micronesia, the Marshall Islands,
Kiribati, Papua New Guinea and the Solomon Islands).
Modelling of future wave climates has been carried out
for 25 tropical Pacific islands, and results suggests that
DecemberFebruary extreme wave heights will decrease
for most islands by 2100 under both an RCP4.5 and RCP
8.5 scenario, although the frequency of the large winter
wave events may increase around the Hawaiian Islands. In
the Caribbean, northerly swells affecting the islands have
been recognised as a significant coastal hazard. They
cause considerable seasonal damage to beaches, marine
ecosystems, and coastal infrastructure throughout the
region.
Transcontinental dust clouds The transport of airborne Saharan dust across the Atlantic Prospero and Lamb
and their impacts into the Caribbean has been intensively studied. In the (2003); Goudie (2014);
West African Sahel, where drought has been persistent Schweitzer et al.
since the mid-1960s, analysis has shown that there have (2018); Goudie (2020)
been remarkable changes in dust emissions since the late
1940s. Variability in Sahel dust emissions may be related Middleton et al. (2008);
not only to droughts, but also to changes in the North Martins et al. (2009);
Atlantic Oscillation (NAO), North Atlantic sea surface Akpinar-Elci et al.
temperatures and the Atlantic Multidecadal Oscillation (2015); Sakhamuri and
(AMO). The frequency of dust storms has been on the rise Cummings (2019)
during the last decade. Forecasts suggest that their
incidence will increase further. Transboundary movement
of Saharan dust into the island regions of the Caribbean
and the Mediterranean has been associated with human
health problems including asthma cases in the Caribbean,
cardiovascular morbidity in Cyprus, and pulmonary
disease in the Cape Verde islands.
Influx of Sargassum from Since 2011, the Caribbean region has witnessed van Tussenbroek et al.
distant sources unprecedented influxes of the pelagic seaweed Sargassum. (2017); Oviatt et al.
These extraordinary sargassum `blooms' have resulted in (2019)
mass deposition of seaweed on beaches throughout the
Lesser Antilles, with damage to coastal habitats, mortality Franks et al. (2016);
of seagrass beds and associated corals, as well as Putman et al. (2018)
consequences for fisheries and tourism. This recent
phenomenon has been linked to climate change as well as
the possible influence of nutrients from Amazon River
floods and/or Sahara dust.
Large-scale changes in the Ocean warming and other climatic phenomena (e.g., El Bell et al. (2018); SPC
distribution of fisheries Niño Southern Oscillation events and Indian Ocean (2019); Oremus et al.
resources Dipole) have been linked to observed oceanic shifts in (2020); Bell et al.
tuna distribution with significant impacts on revenue for (2021); Townhill et al.
vulnerable small island states that depend on fisheries (2021)
licences (e.g., 98% of national income in Tokelau, 66% of
national income in Kiribati). The projected eastward
redistribution of skipjack and yellowfin tuna due to
climate change is expected to reduce the total tuna catch
within the combined EEZs of the 10 Pacific Island
Countries and territories (PICTs) where most purse-seine
activity occurs by approximately 10% by 2050. Projected
increases in tuna biomass have been anticipated for
Ascension Island and Saint Helena in the South Atlantic.
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Movement and impact of The spread of invasive alien species (IAS) is regarded as a Russell et al., 2017)
introduced and invasive significant transboundary threat to the health of
species across boundaries biodiversity and ecosystems worldwide. Vorsino et al. (2014);
Taylor and Kumar
The extent to which IAS (both animals and plants) (2016b)
successfully establish themselves at new locations in a
changing climate will be dependent on many variables, Johnston and Purkis
but non-climate factors such as transmission pathways, (2015); van den Burg et
suitability of the destination, ability to compete and adapt al. (2020)
to new environments, and susceptibility to invasion of
host ecosystems are deemed to be critical. Modelling
studies have been used to project the future `invisibility'
of small island ecosystems subject to climate change and
therefore to anticipate marine and terrestrial habitat
degradation in the future.
Evidence suggests that hurricanes may have hastened the
spread of highly invasive Indo-Pacific lionfish (Pterois
volitans) throughout the Caribbean in recent years. Two
IAS, the Common Green Iguana (Iguana iguana) and
Cuban Treefrog (Osteopilus septentrionalis) were
reported in the Caribbean island of Dominica, following
the passage of TC Maria in 2017. Observations 7 months
after the hurricane, within close proximity to ports,
suggest that these animals were stowaways on ships or
within relief containers.
Spread of pests and Increased climate instability has contributed to the Cao-Lormeau and
pathogens within and emergence and spread of serious diseases carried by Musso (2014);
between island regions mosquitoes such as dengue, chikungunya and zika. The Caminade et al. (2017);
incidence and severity of mosquito-borne diseases have Pecl et al. (2017); Filho
increased significantly in Pacific, Indian Ocean and et al. (2019)
Caribbean islands during the past 10 years, which calls for
a better understanding of how climate change is shaping Maynard et al. (2015);
disease prevalence and transmission. Randall and van
Woesik (2015)
Rising sea temperatures are thought to increase the Bebber (2019)
frequency of disease outbreaks affecting reef-buildings.
Of the range of bacterial, fungal and protozoan diseases
known to affect stony corals, many have explicit links to
temperature. Global projections suggest that disease is as
likely to cause coral mortality as bleaching in the coming
decades at many localities, with effects occurring earlier
at sites in the Caribbean compared to the Pacific and
Indian oceans. Model hindcasts suggest that climate-
driven changes in sea surface temperature, as well as
extreme heatwave events have all played a significant role
in the spread of white-band disease throughout the
Caribbean.
Global food security is threatened by climate-related
increases in crop pests and diseases. Black Sigatoka
disease of bananas has recently completed its invasion of
Latin American and Caribbean banana-growing areas.
Infection risk has increased by a median of 44.2% across
the Caribbean since the 1960s, due to increasing canopy
wetness and improving temperature conditions for the
pathogen.
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Human migration and Currently there is limited empirical evidence that long- Campbell (2014a);
displacement term climate change is driving transboundary human Melendez and Hinojosa
migration from islands, however following Hurricane (2017)
Maria, Puerto Rico witnessed "depopulation" of 14% in
only 2 years as a result of emigration to the US mainland.
Transboundary risks to island While SIDS are a diverse group of nations, most share Connell (2013)
food security. COVID-19 such characteristics as limited land availability, insularity,
caused disruptions to food susceptibility to natural hazards that make them Islam and Kieu (2020);
supply and disaster risk particularly vulnerable to global environmental and Sheller (2020)
management operations economic change processes leading to regional food
insecurity. The Pacific Islands Forum Secretariat (PIFS)
has established a transboundary Framework for Action on
Food Security, that promotes cooperation, investments,
research and development, capacity-building, and
adaptation to mitigate climate change threats.
1
2
3
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1 Table 15.6: Adaptation options aimed at reducing Key Risks in small islands.
Key Risks Risk-oriented adaptation options Evidence and Implementation Key enablers Reduction of Co-benefits Disbenefits
agreement exposure and
vulnerability
MPAs; paired terrestrial Medium Widespread Strong governance and Reduces the For biodiversity,
and MPAs evidence, across small
low islands, with sufficient financial ecosystem food supply,
EbA measures (15.4.4) agreement climate
with regard resilience being resources exposure to economics, human
to climate a target of some
change MPAs human health and well-
adaptation
and benefits disturbances, being
increasing
their
resistance and
resilience to
climate events
Active restoration of Limited Mostly small- Funding: adaptation Reduces the Improved water
coastal and marine vulnerability quality; reduction
ecosystems evidence, scale: replanting taxes and levies of natural in coastal erosion
ecosystems and flood risks;
low of mangroves, imposed on tourism; by increasing economic benefits
their
agreement seagrasses and blue bonds; public- resilience
KR1. Loss of with regard beach private partnerships
marine and
to long-term vegetation;
coastal
biodiversity success transplantation
and of corals; beach
ecosystem Hard protection (15.5.1)
services nourishment
Hard structures designed Medium Artificial reefs Funding: adaptation Uncertainty For food supply,
to enhance marine evidence, and environmental
biodiversity medium taxes and levies, with on reduction economies
agreement limited evidence of
direct reinvestment in of exposure (tourism), human
conservation and
management and health and well-
vulnerability being
of marine
ecosystems;
reduces the
exposure of
population
and
infrastructure
to coastal
risks
Diversifying livelihoods Diversifying fisheries Limited to Examples in the Improved governance Reduces Sustainably
(15.5.6) livelihoods (e.g. to medium Caribbean region and cooperation (e.g. exposure and managed fisheries,
aquaculture and tourism), evidence, and in the through regional vulnerability improved food and
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changing fishing grounds medium Pacific and strategies); weather of livelihoods income security,
through the greater economic
and/or target species agreement Indian Oceans insurance to enhance diversification and social
of income and resilience
resilience spreading of
risks;
targeting less
offshore
pelagic
species
reduces
exposure of
coastal
habitats to
overfishing
Reef-to-ridge ecosystem Improved land use as a Limited Mostly in the Improved governance Reduces the Improved
management (Figure driver of marine ecosystem evidence, Caribbean region exposure of ecosystem
15.4) health, including better medium and Pacific coral reefs to protection services
management of forests, agreement human (e.g. against
nutrients and waster water degradation, flooding,
upland catchments increasing landslides and
their mudflows),
resilience biodiversity,
human health and
livelihoods
Decreased deforestation Limited to Mostly in the NDC, external and For example, Increased
(15.5.4) medium
evidence, Caribbean region long-term funding, increase in connectivity
KR3. Loss of high
terrestrial agreement and Pacific engagement of local forest extent, between forest
biodiversity
and landowners and reduction in fragments, reduced
ecosystem
services resolution of land human erosion, improved
ownership issues, exposure to water supply and
gender sensitive natural quality, improved
participation disasters human health and
(hurricanes, sanitation,
landslides), improved
improvement livelihoods and soil
in health; decreased
vulnerability poverty; supports
assessment global mitigation
scores
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Increased reforestation Towards habitat Medium Relatively NDC, funding, Generally Increased DRR;
(native species) (15.5.4)
connectivity, heterogeneity evidence, widespread, with technical assistance, limited fewer floods and
and diversity high examples in the supply materials, evidence, lack landslides; reduced
agreement Caribbean region provision of land, of long-term erosion; increased
and Pacific awareness raising, monitoring human health and
enforcement of well-being;
policies, sense of increased quality
shared responsibility, of ecosystem
inclusion of Indigenous services; increased
knowledge and local adaptive capacity;
knowledge, social supports global
capital mitigation
EbA (15.5.4) Agroforestry and other Medium Widespread in NDC, shared access Limited Improved climate
the Caribbean change awareness,
silvicultural/agroecological evidence, region and and benefit, local examples, increased well-
Pacific Ocean being, improved
practices (e.g. climate- high knowledge and some gender equity,
improved
smart agriculture) agreement training, farmers, increases in productivity and
livelihoods
private sector for adaptive
developing technology, capacity
financing, data
availability; political,
institutional and
socioeconomic
conditions
Watershed Reforestation, slope Medium Widespread (e.g. Less socially and Yes, through DRD, improved
evidence,
management/conservation revegetation high in the Caribbean politically acceptable improved climate change
agreement
(15.5.4) region and than engineering water awareness,
Pacific Ocean) solutions; security, increased water
communication and reduced security and
trust between adaptation quality, reduced
stakeholders; costs, reduced run-off and
sustainable financing vulnerability sedimentation,
mechanisms; island to drought increased well-
remoteness barrier to being and financial
logistical stability
implementation
Ridge-to-reef ecosystem Improved land use as a Medium See above See above Limited but
evidence, slowly
management (Figure driver of terrestrial high increasing
agreement evidence to
15.4) ecosystem health date
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Increasing the Establishment of new PAs, Very limited Low degree of Conservation of larger Yes, Improved water May facilitate
security, improved movement of
connectivity of Protected forested migration evidence, new areas of forest habitat especially if coastal ecosystem Invasive Alien
health, greater Species
Areas (Pas) across corridors across high implementations surrounding PAs, landscape resiliency and
recovery from
elevation/climatic elevation/climatic agreement due to terrain reforestation of connectivity wildfires, reduced
pollution, DRR
gradients to facilitate gradients, improving limitations degraded areas, is improved
climate-driven landscape connectivity by combined with increasing and (migration
redistribution of species permanent protection of competition enforcement of forest corridors)
(Figure 15.4) stepping stones from human land cover within PAs,
use needs; large policies towards the
variation in PA coordination of
coverage among conservation
islands actions/partnerships,
incorporation of `Other
Effective area-based
Conservation
Measures' (OECMs)
Eradication of Invasive Robust Widespread Integration of changing Yes, positive Food security, A few native
Alien Species (IAS) evidence, (>700 islands)
(15.3.3.3) high climate conditions demographic protection of species harmed
agreement
within ongoing and ecosystem health by eradication
prevention, control and distributional and services, process
eradication strategies, responses of increased
prevention via ongoing native species livelihood security
vigilance and following
biosecurity via eradication of
quarantine, control and IAS
monitoring of incoming
cargo and goods into
islands
Rainwater harvesting Robust h Widespread Socio-cultural and Yes Biodiversity Dependent on
(15.3.4.3)
evidence, across small financial (watershed mode of
high islands (e.g. protection); health; implementation.
agreement Jamaica, economic (reduced Nothing
KR4. Water Barbuda, dependence on mentioned in
insecurity
Solomon public supply); the chapter.
Islands) food security
Desalination (15.6.1) Limited Relatively Financial Yes Health; economic Energy
evidence, limited (e.g.
high Maldives) (reduced intensive
agreement
dependence on (carbon
public supply) footprint)
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Reforestation (15.5.4)
Medium Examples Governance - whole- Yes, through Economic Dependent on
Protected Area evidence, supporting (agroforestry); mode of
Management (terrestrial) high reported in the of-island approaches wetland- biodiversity implementation.
(15.5.4) agreement oriented (watershed Nothing
Caribbean and foster integrated tourism restoration); food mentioned in
Hard protection (15.5.1) Medium security; disaster the chapter.
evidence, Pacific (e.g. Fiji, management practices risk reduction
KR5. Accommodation (15.5.2) high
Destruction agreement Papua New in small islands
of Medium Guinea)
settlements agreement,
limited Widespread Financial/governance Yes, through Biodiversity (forest
and evidence across small
infrastructure with regard islands (e.g. soil conservation);
to climate Samoa, Jamaica,
Advance with land change Haiti, Grenada) stabilization disaster risk
raising and/or through the adaptation
creation of artificial and success and reduction
islands (15.5.2)
Limited sequestration
Do Not Cite, Quote or Distribute evidence
with regard of pollutants
to climate
change Widespread in External funding; Reduces Limited evidence Beach loss;
adaptation of co-benefits erosion
and success both urban and socio-cultural (meets exposure in acceleration;
ecosystem
Limited rural areas of the the preference of the some places degradation
evidence through
with regard Caribbean, population); political- but not in material
to climate extraction;
change Pacific and institutional (e.g. others; increased SLR
adaptation impacts
(driven by Indian Oceans supported by business- increases
population
as-usual approach of vulnerability
coastal risks); technical
(requires materials and
skills)
Relatively Technological, Limited Maintains the
limited functionalities of
financial, institutional, evidence to coastal systems
and allows their
sociocultural date maintenance
through landward
migration, under
SLR
Limited (e.g. Technological, Reduces Offers new land for Widespread
Hulhumale',
Maldives) financial, institutional, population economic ecosystem
sociocultural, high exposure development, destruction,
potential in urban where high generates revenues increased
(compared to rural) standard as in through sale or negative
areas Hulhumale', lease of land in impacts of SLR
Maldives urban areas
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Migration including growth in the
planned resettlement Maldives)
(15.5.3)
Limited Village-scale Participatory inclusion Reduced New livelihood Loss of cultural
evidence, heritage,
low planned of all social groups; exposure opportunities impacts on
agreement receiving
with regard resettlement financial (for small and locally; has communities
to climate
change supported by remote communities); created new
adaptation
government social-cultural vulnerabilities
policy/legislation connections; strong at some
in the Pacific governance locations by
frameworks; enabling bearing
legislation; land significant
availability or economic
ownership; conditions cost,
in receiving locations; impacting
technical support social capital
and reducing
access to
services
EbA measures (15.4.4) Medium Increasingly Environmental/physical Limited Biodiversity
agreement, strengthening;
medium experienced; conditions; social evidence to increased food
evidence supply; increased
includes acceptability; technical date human health and
well-being
artificial reefs, capacities (enhanced by
beach external support);
nourishment and funding; inclusion in
vegetation national adaptation
(including policies
mangrove)
restoration
Increasing public Limited Few examples Financial and human Primarily Increased water
awareness of health risks evidence resources to implement reduces security
associated with climate options; early warning vulnerability
KR6. Health change; providing and response systems;
degradation training to health sector integrating climate
staff; improving services into health
reliability and safety of decision-making
water storage practices systems; public uptake
(15.6.2) and buy in; improving
health data collection
systems
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15-71
Circular migration Limited Examples in Labour and education Yes on Job and education
(15.5.3) opportunities in
evidence Tuvalu from Funafuti, Tuvalu, and Namumea for migrants
overseas
with regard outer to capital Atoll, Tuvalu
to climate atoll and
change locations
adaptation overseas
(mostly
driven by
economic or
social
factors)
Diversifying livelihoods Limited to Observed in the Use of ndigenous Yes in Reduction of Greater catch
(15.5.6) medium pressure on putting
evidence, Caribbean region knowledge and local documented previous fishing increasing
low areas pressure on fish
agreement and Pacific knowledge and places (e.g. stock
changing fishing areas; Antigua,
investment in Vanuatu,
technology and Madagascar,
education Dominican
KR7. Republic)
Economic
decline and Improved technology & Limited Examples in the Investments in Yes in New technologies
livelihood equipment/training evidence, and education
(15.5.6) medium Caribbean region technologies and documented strengthening
failure agreement
and Pacific education (e.g. places
irrigation technologies,
growing salt-tolerant
crops and relocating
crop cultivation in
Jamaica)
Livestock husbandry Limited Limited (e.g. Farm inputs and No evidence Investments in
(15.5.6) evidence small-scale investments in to date. farm inputs
livestock technologies and Limited
husbandry in education examples of
Jamaica) successful
livestock
husbandry
only in
Jamaica
Adaptive Limited Limited (e.g. in Tourism income; Yes, reduces Generates
finance/education evidence, Puerto Rico, opportunities (e.g.
(15.5.6) medium women engage investment in education risk and for wetland
agreement in new tourism)
Do Not Cite, Quote or Distribute and capacity building; avoids
negative
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commercial working with nature knock-on
enterprises that and EbA effects
do not rely on
traditional coffee
supply chains or
government
assistance)
Product/Market Diversity of crops, Medium Examples in the Availability of crops Reduces Increases food
diversification (15.5.6) Caribbean region and land, new markets
gardening in different evidence, and Pacific vulnerability security and
areas, storage and high to tropical improves nutrition;
preservation of foodstuffs, agreement cyclones in increases income
engagement of women in Fiji and security
new commercial Vanuatu; new
enterprises markets in
Puerto Rico
Adaptation in tourism Limited Limited (e.g. in Tourism regulations Limited
policies (15.5.6) evidence, the British and policies that evidence in
high
agreement Virgin Islands, mainstream climate reducing
policies like change adaptations; vulnerability
adaptation taxes taxes and levies
and levies imposed on tourism
imposed on
tourism can
provide funding
for adaptation
measures)
Integrating Indigenous Medium Reported in the Use of IKLK for Yes, can Can increase Reports from
Knowledge and local evidence, Pacific and
knowledge (IKLK) with high Caribbean preparing for disasters reduce climate change Vanuatu
western science to agreement
provide integrated and understanding vulnerability information and its indicates that
approaches to climate
change (15.6.5) environmental change; when IK LK understanding in IK LK are at
KR8. Loss of social networks in supports communities, and times inaccurate
cultural
resources sharing information robust increase culturally (eg seasonal
and heritage and helping others; adaptation; appropriate climate calendars,
ecotheology increasing No, can adaptation biophysical
people's awareness of increase weather
the environment vulnerability indicators) due
if IKLK no to climate
longer change
provides
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Hard protection (15.5.5.1)
accurate
1 information
Medium Widespread in External funding; Reduces Limited evidence Beach loss;
agreement, of co-benefits erosion
limited protecting socio-cultural exposure in acceleration;
evidence ecosystem
with regard cultural sites and (generally meets the some places degradation
to climate through
change villages in both preference of the but not in material
adaptation extraction;
and success urban and rural population); political- others; increased SLR
impacts
areas of the institutional (e.g. increases
Caribbean, supported by business- vulnerability
Pacific and as-usual approach of
Indian Oceans coastal risks); technical
(requires materials and
skills)
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1 Table 15.7: Enabling Conditions and Factors for Adaptation in Small Islands
Enabling Conditions and Factors for Adaptation
Enabler Example Reference
Knowledge (Indigenous, Local, External)
IKLK in developing Using IKLK in identifying Indigenous vegetation Crichton and Esteban (2018); Nalau
(e.g., ecosystem-based adaptation) to reduce et al. (2018b)
erosion (Samoa, Vanuatu)
adaptation strategies (soft
protective structures; disaster Pacific storm prediction, disaster preparedness Chand et al. (2014); Kuruppu and
preparedness) Willie (2015); Granderson (2017)
Shared resource governance and understanding of
linkages between sectors and ecosystems based Remling and Veitayaki (2016)
on IKLK (e.g., Lomanu Gau village initiative
(Fiji)
Increased access to climate Increased access to climate information Di Falco and Sharma-Khushal
information increasing individuals will and capacity to (2019)
support/take adaptive actions (Fiji)
Dissemination of adaptation skills and McNaught et al. (2014)
significance to youth (e.g., Ecocamps in Fiji)
Pacific women's improved participation in McLeod et al. (2018)
adaptation processes via training, access to
information and decision-making
Improved climate data quality, management and Martin et al. (2015); Hermes et al.
Increased access to climate associated observation, modelling and (2019)
information (continued)
information services
Caribbean: Improved climate data quality, Trotman et al. (2018)
management and associated observation,
modelling and information services SPREP (2016a)
Provision of user-tailored products and services Loehr (2019); Mahadew and
through knowledge co-production processes Appadoo (2019); Loehr et al. (2020);
Sheller (2020)
Economy and Finance Rambarran (2018)
Economic diversification and Tourism system transitions/cooperation from
shifting to CRDPs tourism sector
Innovative financing models that enable
adaptation (e.g., Seychelles)
Finance models for adaptation Parametric fisheries insurance products to
increase fishery resilience funded by Caribbean CCRIF (2019)
Catastrophe Risk Insurance Facility (Grenada and
Saint Lucia)
Transregional trade Revised socio-political arrangements for better Keen et al. (2018)
agreements/associated fisheries management (Solomon Islands)
pressure
Maldives land raising on Hulhumale Bisaro et al. (2019)
Economic viability via
revenue from sale of new land "Safe island development programme" after 2004
Indian Ocean Tsunami in the Maldives Shaig (2008)
Government subsidies Tuamotu's government subsidy of raised houses Magnan et al. (2018)
Co-investments and Tuvalu use of beach nourishment in collaboration Onaka et al. (2017)
cooperation between agencies with JICA
(donors, governments)
Blair and Momtaz (2018)
Diversification of livelihoods Coastal fishers' diversification of livelihoods into
as basis for economic activity the tourism sector (Vanuatu and Madagascar)
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Fishermen varying fishing practices and locations Karlsson and McLean (2020)
depending on environmental conditions (e.g.,
Dominican Republic)
Governance Improved governance arrangements: Cross- Webb et al. (2015); Nalau et al.
Changed governance sectoral and cross-agency coordination (e. g. (2016)
arrangements resulting in Vanuatu)
improved coordination Turner et al. (2020)
Agency explicitly tasked with coordinating
Changed governance sectors and services for climate resilience across McGinn and Solofa (2020)
arrangements resulting in government (Dominica)
improved coordination
(continued) Efficient and coordinated distribution of climate
New strict/explicit building adaptation support across national projects and
codes departments (e.g., Samoa)
Caribbean infrastructure (esp. housing and hotels) Mycoo (2018a)
now must be built to withstand strong hurricanes
Pacific Adaptive Capacity Framework Warrick et al. (2017)
Localising climate adaptation Framework for the Disaster and Climate Resilient SPC (2016)
plans, frameworks and Development in the Pacific (FRDP)
policies
Island-centric adaptation policy and planning Schwebel (2017)
Social and cultural
Support of social networks in hurricane recovery,
access to livelihood opportunities (e.g., Turner et al. (2020)
Social networks and capacity Dominica)
in disaster recovery
Increased Indigenous resilience and adaptive Petzold and Ratter (2015); Parsons et
capacity via social networks and capital (e.g., al. (2018)
Samoa)
Informal credit for fishermen at food stores Karlsson and McLean (2020)
during and after disasters (e.g., Belize and
Dominican Republic)
Social networks and Community-level fundraising (e.g., Samoa, Birk and Rasmussen (2014); Carby
traditional familiarity with Solomons, Jamaica) (2017); Crichton and Esteban
barter/microfinance (2018); Parsons et al. (2018); Nunn
and Kumar (2019a)
Maintenance of home Circular migration between Tuvalu and overseas Marino and Lazrus (2015)
community
Empowerment of the Relocations of villages (Fiji) Marino and Lazrus 2015)
migrating individuals
1
2
3 Table 15.8: Research Gaps in Small Islands
Research Gap Elaboration
There is a lack of oceanographic (e.g. tidal), meteorological, high resolution topographic and
bathymetric data, as well as future sea-level and wave climate projections for most islands,
which severely constrain modelling studies and therefore improved understanding of future
coastal flooding, erosion, and rates of saline intrusion into aquifers (Giardino et al., 2018; Lal
and Datta, 2019)
Unavailability of There is a need for further developing context-specific numerical models, especially through the
adequately inclusion of sediment transport, production and delivery (Shope and Storlazzi, 2019), coastal
downscaled and marine ecosystems' responses (Beetham et al., 2017), and various societal responses (e.g.,
climate data engineering and ecosystem-based solutions (Giardino et al., 2018)) under different climate
change and SLR scenarios.
The complexity and specificities of small island environments and unavailability of robust
baseline data considerably challenge modelling studies in small islands contexts, as reflected by
the serious limitations of global modelling impact studies for these (Mentaschi et al., 2018;
Vousdoukas et al., 2020).
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Data and model developments are therefore urgently needed to assess the future habitability or
exploitability of the islands that are the most critical to small island countries and territories, and
to help identify and promote appropriate (especially in technical terms) solutions.
Adequately downscaled Regional Climate Model (RCM) data (sub-5 km2) is also required to
conduct modelling assessments for small island terrestrial ecosystems. This is particularly
needed for islands with complex topography which could be important in providing much-
needed climate refugia for the survival of narrow range species such as endemics (Balzan et al.,
2018). Such spatial data could be used to maximize the potential of islands to deliver critical
ecosystem services (Katovai et al., 2015; Balzan et al., 2018).
Widely used WorldClim data may not be suitable when applied to the small island context (Box
CCP1.1) Without such data, robust ecosystem based adaptation strategies such as climate-smart
protected area planning and management under changing climate conditions cannot be
developed.
Thomas and Benjamin (2017) highlighted the lack of data as an area of concern related to
assessing loss and damage at 1.5°C. Understanding loss and damage also requires more detail on
island-specific losses and damages accruing from anthropogenic climate change impacts. At the
moment, such assessments are limited, and most of the small islands have not yet documented
these factors in their national adaptation plans or policies (Handmer and Nalau, 2019). There is a
need for specific studies also on biophysical variables and species (e.g. impact of temperature
rise on mangroves); long term impacts of ocean acidification on species, including relationship
to disease outbreaks, and changing breeding grounds of marine species and impacts on fisheries
and marine-based livelihoods; incorporating biophysical feedback and interconnectivity of
environments into models; and more detailed datasets (e.g. bathymetry, coastal assets) (World
Bank, 2016; McField, 2017; Wilson, 2017).
There is need for new research that investigates the variability of vulnerability within and
between islands and states, typologies of best practice (Oculi and Stephenson, 2018), frequency
of knowledge sharing among islands and regions (Foley, 2018), identification of regional
framework mechanisms, and mapping the complex impact and hazard interactions at a regional
scale (Duvat et al., 2017b; Neef et al., 2018; Scandurra et al., 2018; Thiault et al., 2018).
Research needs to also examine resilience-building efforts within the four domains of islandness
(boundedness, smallness, isolation, and littorality) to effectively capture subjective nuances
associated with climate development efforts on islands (Kelman, 2018).
Research gaps in place-based assessments of social service bundles coupled with policy actions
(Balzan et al., 2018) highlight the need for new knowledge to strengthen communication,
collaboration and networks between academia, donors, the private sector, community and
government (Allahar and Brathwaite, 2016; Schipper et al., 2016) so as to improve
understanding of vulnerability and resilience in small islands.
A paucity of research exists currently on the vulnerability of island ecosystem services to
climate change (Balzan et al., 2018). While there is rich scientific evidence on the pressures of
habitat loss and degradation, impacts of natural hazards and invasive species, far less is known
about the interactions of these factors with adaptive capacity and livelihood conditions on
Vulnerability and islands. In small island contexts, there is a specific need for assessing the effectiveness and cost
Resilience of ecosystem - and community-based solutions where the latter have been implemented (Filho et
al., 2020). The design of generic assessment methods and tools is required to allow for
comparative analyses that will, in turn, provide useful guidance for the promotion of context-
specific adaptation strategies (Blair and Momtaz, 2018). For many of the small islands,
especially SIDS, the economic valuation of marine and coastal ecosystem services coastal
protection, fisheries, tourism - is of great importance, as well as the subsequent losses in these
sectors and related livelihoods due to climate change impacts (Waite et al., 2014; Schuhmann
and Mahon, 2015; World Bank, 2016; Layne, 2017; Duijndam et al., 2020). There are few
integrated modelling studies to inform future habitability of differentiated small island types and
how these models can inform decision support processes for ridge to reef stewardship (Povak et
al., 2020). Existing studies (Rasmussen et al., 2018) have progressed knowledge since AR5, but
island-specific analyses are required to robustly estimate the future ability of land to support life
and livelihoods, taking into account multiple climate-drivers, future population exposure, and
adaptation responses.
More research is also needed in understanding how ecosystem benefits are modified under
changing climate conditions and how these benefits can be quantified (Doswald et al., 2014).
For example, many small islands lack comprehensive (and disaggregated) data related to food
security which makes it challenging to attribute climate impacts on local food systems (Taylor et
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Adaptation al., 2019). Balzan et al. (2018) highlight the importance of quantifying the role of biodiversity in
delivering key ecosystem services and demonstrate how such data could provide insights on the
1 interrelatedness of island ecosystems and transboundary service benefits.
2
3 In the last decade or so, there has been a significant increase in climate-related financing for
small island states. However, monitoring and tracking of funding and metrics to evaluate overall
impact are lacking (Boyd et al., 2017; Mallin, 2018). Research into adaptation costs could
benefit from the inclusion of indirect effects of climate change such as psychological costs
(Vincent and Cull, 2014; Gibson et al., 2019) but to date this research is missing. Greater effort
could also be placed on quantifying the relationship between adaptation costs and adverse events
(Adelman, 2016). There is also a need for overall land use planning guidelines in small coastal
communities, including small islands (Major and Juhola, 2016). The usefulness and utility of
insurance mechanisms for building resilience to climate hazards require up to date information
on assets at risk (Tietze and van Anrooy, 2018) and further exploration of adaptation measures
in small island contexts (Baarsch and Kelman, 2016). Additionally, the differences between
theoretical adaptation practices and observed results from actual implementation, along with the
integration of IKLK and external knowledge are currently not well understood (Mercer et al.,
2014b; Kelman, 2015b; Saint Ville et al., 2015; Robinson and Gilfillan, 2016; Robinson,
2017b). Documenting experience-based knowledge of adaptation projects and programme
implementation could fill important data gaps. At the project design stage, paucity of climate
finance data is a barrier to accessing climate finance (Bhandary et al., 2021).
Although studies examining the association between climate and weather extremes, events and
conditions and mobility in small islands have increased since AR5 (Birk and Rasmussen, 2014;
Kelman, 2015a; Connell, 2016; Stojanov et al., 2017; Barnett and McMichael, 2018), few
studies robustly examine attribution of migration of small island populations, communities and
individuals to anthropogenic climate change and other non-climate migration drivers.
Biophysical, socio-economic and in-situ adaptation threshold that force small island populations
to migrate remains under-explored (Barnett, 2017; Handmer and Nalau, 2019). The implications
of forced and voluntary immobility (Allgood and McNamara, 2017; Farbotko, 2018; Suliman et
al., 2019), the socio-economic, health, psychological and cultural outcomes of climate migrants,
and gender dimensions of climate migration all remain under-researched.
Limits to adaptation is still a largely under-researched topic globally (Nalau and Filho, 2018)
and specifically in small island contexts, as are the linkages between adaptation limits, loss and
damage and transformative adaptation (Thomas et al., 2020). In terms of projected risks and
adaptation responses, further work is needed to improve knowledge of commonalities,
differences, successes, and failures of natural and human adaptation responses (Kuruppu and
Willie, 2015). One of the failings of current literature on limits to adaptation revolves largely on
the use of barriers for sector-specific or small-scale scenarios, that provide an understanding
only for that particular scenario and does not identify common constraints (Kuruppu and Willie,
2015). Research gaps on loss and damage include: how to assess the economic costs of loss and
damage; mechanisms to develop robust policies in small island contexts; specific data on
experienced loss and damage across socio-economic groups and demographics; monitoring and
tracking of slow onset events (Thomas and Benjamin, 2017; Thomas et al., 2020) and the non-
economic aspects including sense of place, health and community cohesion (Thomas and
Benjamin, 2019).
More studies are needed on the role that organisations (international, national and regional) play
in adaptation efforts their effectiveness at achieving desired outcomes, roles and accountability
(Robinson and Gilfillan, 2016; Scobie, 2016; Mallin, 2018). It is also important that the impacts
of socio-political relations inter-state are researched (Belmar et al., 2015) and more focus on
climate justice (Baptiste and Devonish, 2019; Moulton and Machado, 2019; Gahman and
Thongs, 2020) and gender are similarly needed (Mcleod et al., 2018). Given the high number of
place-specific case studies in adaptation literature, more reviews are needed that synthesise key
lessons and principles of adaptations in small island contexts from this knowledge. Further
research is also needed to capture the lessons from COVID-19 response in small islands and
how these could enable more robust adaptation and climate resilient development transitions as
has been suggested at a broader scale by Schipper et al. (2020). There is also little to no
information on impacts upon terrestrial and freshwater biodiversity from the relocation of
coastal human populations inland due to SLR.
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