FINAL DRAFT                       Cross-Chapter Paper 6     IPCC WGII Sixth Assessment Report


2                                     Cross-Chapter Paper 6: Polar Regions


4 Cross-Chapter Paper Leads: Andrew J. Constable (Australia), Sherilee Harper (Canada)


6 Cross-Chapter Paper Authors: Jackie Dawson (Canada), Kirstin Holsman (USA), Tero Mustonen

7 (Finland), Dieter Piepenburg (Germany), Bj鰎n Rost (Germany)


9 Cross-Chapter Paper Contributing Authors: Stef Bokhorst (The Netherlands), Julia Boike (Germany),

10 Ashlee Cunsolo (Canada), Chris Derksen (Canada), Pauliina Feodoroff (Finland), James D. Ford (United

11 Kingdom/Canada), Stephen E.L. Howell (Canada), Ang閘ica Casanova Katny (Chile), Joanna Petrasek

12 MacDonald (Canada), 舠hild 豱vik Pedersen (Norway), Sharon Robinson (Australia), Dalee Sambo

13 Dorough (USA), Vyacheslav Shadrin (Russian Federation), Mette Skern-Mauritzen (Norway), Sharon Smith

14 (Canada), Dmitry Streletskiy (USA/Russian Federation), Megumu Tsujimoto (Japan), Brie Van Dam (USA)


16 Cross-Chapter Paper Review Editor: Philip Boyd (Australia)


18 Cross-Chapter Paper Scientist: David Babb (Canada)


20 Date of Draft: 1 October 2021


22 Notes: TSU Compiled Version



25 Table of Contents


27 Executive Summary..........................................................................................................................................2

28 CCP6.1 The Global Importance of Climate Change in Polar Regions ..................................................5

29 CCP6.2 Observed Impacts and Future Risks...........................................................................................9

30  CCP6.2.1 Marine and Coastal Ecosystems...........................................................................................11

31  CCP6.2.2 Terrestrial and Freshwater Ecosystems ...............................................................................15

32  CCP6.2.3 Food, Fiber, and other Ecosystem Products ........................................................................16

33 FAQ CCP6.1: How do changes in ecosystems and human systems in the polar regions impact everyone

34  around the globe? How will changes in polar fisheries impact food security and nutrition around

35  the world?................................................................................................................................................19

36  CCP6.2.4 Economic Activities...............................................................................................................21

37 FAQ CCP6.2: Is sea-ice reduction in the polar regions driving an increase in shipping traffic?...........23

38 Box CCP6.1: Climate Change and the Emergence of Future Arctic Maritime Trade Routes ...............24

39  CCP6.2.5 Arctic Settlements and Communities ....................................................................................26

40 FAQ CCP6.3: How have Arctic communities adapted to environmental change in the past and will

41  these experiences help them respond now and in the future? ............................................................27

42  CCP6.2.6 Human Health and Wellness in the Arctic............................................................................27

43 Box CCP6.2: Arctic Indigenous Self-determination in Climate Change Assessment and Decision-

44  making .....................................................................................................................................................29

45 CCP6.3 Key Risks and Adaptation..........................................................................................................32

46  CCP6.3.1 Key Risks...............................................................................................................................32

47  CCP6.3.2 Adaptation.............................................................................................................................35

48 FAQ CCP6.4: When will climate change impacts in polar regions surpass our ability to adapt? .........42

49 CCP6.4 Climate Resilient Development Pathways ................................................................................42

50  CCP6.4.1 Challenges to Climate Resilient Development Pathways .....................................................43

51  CCP6.4.2 Inclusive, Integrated Co-management..................................................................................43

52  CCP6.4.3 Enabling Climate Resilience in the Arctic: Self-determination and Indigenous Peoples'

53               Rights ....................................................................................................................................44

54 CCP6.5 Summary and Conclusion ..........................................................................................................44

55 References .......................................................................................................................................................46



    Do Not Cite, Quote or Distribute  CCP6-1                                            Total pages: 66
FINAL DRAFT                       Cross-Chapter Paper 6  IPCC WGII Sixth Assessment Report

 1 Executive Summary
 3 Observed impacts and future risks
 5 Climate change impacts and cascading impacts in polar regions, particularly the Arctic, are already
 6 occurring at a magnitude and pace unprecedented in recent history (very high confidence), and much
 7 faster than projected for other world regions (high confidence1).
 9 The polar regions, notably the Arctic and maritime Antarctic, are experiencing impacts from climate
10 change at magnitudes and rates that are among the highest in the world, and will become profoundly
11 different in the near-term future (by 2050) under all warming scenarios (high confidence). In the
12 Arctic, accelerated sea-ice loss (particularly during summer), increased permafrost thaw and extreme high
13 temperatures have substantially impacted marine, freshwater and terrestrial sociological-ecological systems
14 (very high confidence). Multiple physical, ecological and societal elements of polar regions are approaching
15 a level of change potentially irreversible for hundreds of years, if not millennia (high confidence). Evidence
16 of borealization of terrestrial and marine systems is emerging (high confidence), and cascading impacts are
17 on-going and widespread yet challenging to quantify fully due to complexity and lags in ecological
18 expression of change. Loss of multi-year sea-ice and the occurrence of a seasonally ice-free Arctic Ocean by
19 the middle of this century will result in substantial range contraction, if not the disappearance of several
20 Arctic fish, crab, bird and marine mammal species, including possible extinction of seals and polar bears in
21 certain regions (high confidence). In the Arctic, permafrost thaw and snowfall decrease lead to profound
22 hydrological changes, an overall greening of the tundra and regional browning of tundra and boreal forests
23 (high confidence). (CCP6.1; Table CCP6.1; Table CCP6.2; CCP6.2.1; CCP6.2.2; Table CCP6.5)
25 Contractions of the polar climate zones lead to distribution shifts and changes in food webs, induce
26 declines in many species (medium confidence) with impacts on subsistence harvests and commercial
27 fisheries, and threaten global dependence on polar regions for substantial marine food production
28 (high confidence). Climate change has induced food web changes resulting in population declines in polar
29 seabirds, including penguins, and marine and terrestrial mammals (high confidence). Globally and regionally
30 important harvested fish and invertebrate species are also contracting ranges and declining productivity,
31 including Pacific cod, salmon, snow and king crab in the Arctic and krill in the Antarctic (medium
32 confidence), with implications for global food systems (high confidence). (Table CCP6.2; CCP6.2.1;
33 CCP6.2.3; Table CCP6.3; Table CCP6.4)
35 Loss of sea-ice is rapidly expanding opportunities, but also increasing risks for shipping and other
36 economic industries in polar regions (very high confidence). Reduced sea-ice enables greater access to
37 high-latitudinal seas for industries, such as fisheries, shipping, tourism (very high confidence) and Arctic
38 maritime trade and resource extraction (medium confidence). Navigational risks have grown due to
39 increasingly mobile multi-year ice, poor hydrographic charting in newly open areas, and limited weather,
40 water, ice, and climate data and services (high confidence). Cascading risks from polar shipping growth
41 include increased air emissions, underwater noise pollution, disruption to subsistence hunting and cultural
42 activities in the Arctic (high confidence) and potential for invasive marine species and geopolitical tensions
43 (medium confidence). (Table CCP6.3; CCP6.2.4; Box CCP6.1; Table CCP6.5; Table CCP6.6)
45 Increased permafrost thaw and flooding will disrupt economically important transportation and
46 supply-chain infrastructure to remote Arctic settlements (high confidence), increasing risks to
47 economies, Arctic tourism and tourism to cultural heritage sites (medium confidence). Arctic permafrost
48 thaw is projected to impact most infrastructure by the middle of this century, impacting millions of people
49 and their economies, and costing billions in damages (high confidence). (CCP6.2.3; CCP6.2.4; Box CCP6.1;
50 CCP6.2.5; CCP6.3.1; Table CCP6.5; Table CCP6.6)

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.

Do Not Cite, Quote or Distribute  CCP6-2                 Total pages: 66
FINAL DRAFT                       Cross-Chapter Paper 6  IPCC WGII Sixth Assessment Report

 1 Climate change increasingly threatens many facets of Arctic livelihoods, culture, identity, health and
 2 security, particularly for Indigenous Peoples (very high confidence). It has negatively impacted mental
 3 health and increased risks of injury, food insecurity and foodborne and waterborne disease, with risks
 4 amplified for those reliant on the environment for subsistence, livelihoods and identity (high confidence).
 5 Permafrost thaw, sea-level rise and reduced sea-ice protection have already damaged or destroyed many
 6 cultural heritage sites in some Arctic regions (very high confidence) and are projected to continue across all
 7 Arctic regions (very high confidence). (CCP6.2.3; Table CCP6.3; CCP6.2.4; CCP6.2.5; CCP6.2.6; Figure
 8 CCP6.3; Box CCP6.2; CCP6.3.1; Table CCP6.5; Table CCP6.6)
10 Adaptation
12 Adaptations to manage climate change impacts and risks in polar regions are urgently needed (very
13 high confidence), but implementation is uneven (high confidence), limits to adaptation are high and
14 maladaptation is probable (high confidence).
16 Polar zones will continue to contract and diminish in extent under climate change, and local
17 adaptations will be insufficient to achieve long-term resilience of polar systems (medium confidence).
18 The pace and extent of change in polar regions is challenging the ability of social and natural systems to
19 adapt (medium confidence). Management of different sectors with specific measures to reduce the potential
20 for compounding risks and the development of climate-sensitive strategies would support the resilience of
21 polar systems. Resilience of natural systems can be enhanced through strategies that maintain ecological
22 connectivity over large spatial scales and reduce the particular impact of local extreme events on biodiversity
23 (medium confidence). (CCP6.2; Box CCP6.1; CCP6.3; Table CCP6.5; Table CCP6.6; Figure CCP6.6;
24 CCP6.4)
26 Timing, direction and scale of polar climate change impacts differ sub-regionally and will require
27 adaptation strategies that are flexible, equitable, inclusive and integrated across sectors and
28 governance arrangements to effectively reduce risks (high confidence). Governance around climate
29 change planning, preparation and response has been limited in scope, and has often not considered
30 interacting effects of climate change with other risks (high confidence). Reactive management strategies will
31 not succeed in reducing risks in polar regions given the rapid change and increasing potential for extreme
32 events (high confidence). Greater inclusivity of stakeholders and communities, along with using diverse
33 sources of information, including Indigenous knowledge and local knowledge, can benefit robust planning
34 and decision-making, and uptake of adaptations (high confidence). Effectiveness in preparing for and
35 adapting to climate risks can benefit from improved climate, weather and ice forecasting services, tools for
36 integrating climate change data and different types of knowledge into management processes and enhanced
37 polar search, rescue, and emergency response capabilities (high confidence). (CCP6.2.3.1; CCP6.3; Table
38 CCP6.6; CCP6.4; Box CCP6.2; Box CCP6.3; Figure CCP6.8)
40 Climate resilient development
42 Climate resilience for Arctic Indigenous Peoples and local communities is dependent on Indigenous
43 self-determination in climate-adaptation action (very high confidence), inclusive, coordinated, and
44 transboundary governance (high confidence) and ecosystem-based policies (high confidence) to
45 effectively address climate change impacts and risks across scales and sectors, and to achieve a
46 resilient, secure and equitable future.
48 Development of robust pathways for climate resilience in the Arctic can be accelerated by adaptation
49 strategies and governance that reflect local conditions, cultures and adaptive capacities of
50 communities and sectors (high confidence). Effectiveness of adaptation strategies will be enhanced by
51 accounting for the geographic, climatic, ecological and cultural uniqueness of the polar regions (medium
52 confidence). Colonialism can inhibit the development of robust climate adaptation strategies, and exacerbate
53 climate risks (very high confidence). Inclusive decision-making in establishing climate adaptations can foster
54 resilience, reflect the unique environmental, cultural, and economic imperatives of the region and support
55 both market-based and sharing economies (high confidence). (Box CCP6.2; Table CCP6.6; CCP6.3.2;
56 CCP6.4)

Do Not Cite, Quote or Distribute  CCP6-3                 Total pages: 66
FINAL DRAFT                       Cross-Chapter Paper 6  IPCC WGII Sixth Assessment Report

1 Indigenous self-determination in managing climate change impacts, adaptations, and solutions can
2 accelerate effective robust climate-resilient development pathways in the Arctic (very high confidence).
3 Arctic Indigenous self-determination in decision-making can establish robust climate resilience, especially in
4 Indigenous communities, incorporating locally-derived definitions of social and economic success, culturally
5 legitimate institutions of government, strategic visioning and thinking and public-spirited, nation-building
6 leadership (very high confidence). (Box CCP6.2; CCP6.3; CCP6.4)

Do Not Cite, Quote or Distribute  CCP6-4                 Total pages: 66
    FINAL DRAFT                       Cross-Chapter Paper 6                   IPCC WGII Sixth Assessment Report

1 CCP6.1         The Global Importance of Climate Change in Polar Regions


3 Polar regions (Figure CCP6.1) are considered flagship areas for climate change, since some of the most

4 extreme climate change impacts that are projected to occur by 2050 elsewhere in the world have already

5 been observed in the Arctic and Antarctic and have resulted in transformative and unprecedented change.

6 Polar regions are not only home to cultural keystone species such as polar bears (Arctic) and penguins

7 (Antarctic), they also play fundamental roles in regulating the global climate system and in the provision of

8 ecosystem services for the global community and for Arctic Indigenous Peoples and local communities in

9 the region.


11 These changes are causing a suite of direct and cascading risks for all polar ecosystems with larger effects to

12 date in the Arctic than the Antarctic (high confidence), due to larger and regionally more consistent physical

13 changes (Figure CCP6.2, Table CCP6.1; Chapter 3) (Meredith et al., 2019; Ranasinghe et al., 2021). In the

14 Arctic, these changes affect every sector of society, impacting its 4,000,000 inhabitants, including 400,000

15 Indigenous People. The Antarctic has no permanent human settlements; however, many nations conduct

16 field research, operate seasonal and permanent stations and have an interest in the management of the region

17 (Hughes et al., 2018; Grant et al., 2021). During summer, when Antarctic science, tourism and fishery

18 activities are greatest, 4,400 people live there, whereas only 1,100 people live there over winter (Meredith et

19 al., 2019). Although adaptation is occurring in polar regions, it is uneven and sporadic and does not meet the

20 risks posed by future climate change. Indigenous knowledge-based solutions, inclusive ecosystem-based

21 policies and integrated technologies demonstrate the potential to effectively address climate change impacts

22 across scales and sectors; yet implementation barriers remain (CCP6.4.1).


24 This Cross Chapter Paper (CCP) assesses the impacts, risks and adaptation implications resulting from the

25 physical and chemical changes in the polar regions that were detailed in the WGI contribution to the AR6

26 (IPCC, 2021). Several key WGI AR6 findings have important implications for natural and human systems in

27 polar regions. Warming and wetting have persisted as key climatic impact drivers in polar regions (very high

28 confidence) and will very likely2 continue to 2100 (Fox-Kemper et al., 2021; Gulev et al., 2021) with

29 cascading climate effects regarding heatwaves, fire, weather, floods and heavy precipitation, river runoff,

30 snowfall, glaciers and ice sheets, permafrost, lake, river and sea-ice, relative sea level and coastal flooding

31 and erosion (Guti閞rez et al., 2021; Ranasinghe et al., 2021) (Table CCP6.1). They represent major climate

32 hazards in all key risks for polar regions (Table CCP6.5). Key points of departure for this CCP also include

33 AR5 (IPCC, 2014) and the Polar Regions chapter in the Special Report on the Ocean and Cryosphere in a

34 Changing Climate (SROCC) (Meredith et al., 2019). SROCC assessed physical, biological and social

35 systems concerning the Arctic and Antarctic Oceans and cryosphere, and how they are affected by current

36 and future climate change. This CCP assesses the rapidly increasing evidence that has been published since

37 AR5 and SROCC, and advances previous IPCC assessments. First, results from the Coupled Model

38 Intercomparison Projects (CMIP6) are an important advance since SROCC, which improve the certainty and

39 resolution of projections of the main climate impact drivers and the risks they have for polar systems (Fox-

40 Kemper et al., 2021; Ranasinghe et al., 2021). Second, building from the framework outlined in SROCC

41 (Crate et al., 2019), scientific, Indigenous knowledge (IK) and local knowledge (LK) systems are included in

42 this assessment. Importantly, Indigenous authors led the assessment of the impacts, adaptation and

43 governance of climate change for Indigenous Peoples, which is an important advance since AR5 and

44 represents an important step towards Indigenous self-determination in international assessment processes

45 (Ford et al., 2012; Ford et al., 2016; Hill et al., 2020).


47 Herein, observed impacts and future risks (CCP6.2), key risks and adaptation (CCP6.3) and climate resilient

48 development pathways (CCP6.4) in the polar regions are assessed. The CCP describes how the implications

49 of climate change impacts in the Arctic and Antarctic extend beyond their boundaries, in terms of

50 transregional coupled ecological systems (CCP6.2.1, CCP6.2.2), global nutritional security (CCP6.2.3),

51 global trade and shipping (CCP6.2.4) and cultural value (CCP6.2.5, CCP6.2.6). Given the synthetic and

    2 In this Report, the following terms have been used to indicate the assessed likelihood of an outcome or a result:
    Virtually certain 99�100% probability, Very likely 90�100%, Likely 66�100%, About as likely as not 33�66%,
    Unlikely 0�33%, Very unlikely 0�10%, and Exceptionally unlikely 0�1%. Additional terms (Extremely likely: 95�
    100%, More likely than not >50�100%, and Extremely unlikely 0�5%) 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.

    Do Not Cite, Quote or Distribute  CCP6-5                                  Total pages: 66
FINAL DRAFT                       Cross-Chapter Paper 6   IPCC WGII Sixth Assessment Report

1 policy-facing mandate of CCPs and with SROCC as a key point of departure, this CCP is not intended to
2 cover the full breadth of issues for polar regions but rather it highlights select key policy-relevant topics by
3 synthesizing and adding value to the relevant material from AR6 sectoral and regional chapters.


 7 Figure CCP6.1: Polar regions include the Arctic, Antarctica, Iceland, Greenland, Faroe Islands, and some sub-Arctic
 8 areas (e.g., Bering Sea and Aleutian Islands as well as the Fennoscandian and Siberian boreal areas), and all sub-
 9 Antarctic areas. This CCP augments the geographical boundaries for the Arctic (Meredith et al., 2019) to also include
10 the subarctic boundary (as defined by the Arctic Biodiversity Assessment), northern boreal areas, parts of the Siberian
11 taiga and southern Labrador. The Antarctic region is delineated along the sub-Antarctic Front (Orsi et al., 1995).
12 Geographic boundaries of the polar regions and important sub-regional locations are displayed including five marine
13 sectors as defined in the Marine Ecosystem Assessment for the Southern Ocean (MEASO), e.g., Grant et al., (2021).
16 Table CCP6.1: Climatic impact drivers in the Arctic and Antarctic derived from WGI-AR6 chapters (indicated as
17 WG1-9 (Fox-Kemper et al., 2021) and WG1-12 (Ranasinghe et al., 2021)) and Meredith et al (2019) (indicated as
18 SROCC-3). Supplementary Material (SMCCP6.1) contains supplemental data for these drivers of projected changes
19 (2021-2040, 2041-2060, 2081-2100) derived from the WGI-AR6 Interactive Atlas (indicated as Atlas)(Guti閞rez et al.,
20 2021)(

Driver       Region Observed Changes                      Projected Changes

Marine and sea-ice

Sea level    Arctic  No consistent trend (increase in NW  Rise in all polar regions (except areas of
                     America, decrease in NE America, stable substantial land uplift in NE Canada, the

                     in Greenland and Arctic Russia) (WG1-12) west coast of Greenland) (high


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                                                                     Increase of extreme sea levels in Russian
                                                                     Arctic and NW America (high confidence)
                                                                     Greenland/Iceland and NE America
                                                                     (given glacial isostatic adjustment)
                                                                     (medium confidence, WG1-12)

             Antarctic                                               Rise in all polar regions (except areas of
                                                                     substantial land uplift in W Antarctica)
                                                                     (high confidence, WG1-12)

Sea-surface  Arctic     Increase of ~0.5癈 per decade during         Further increases (high confidence, WG1-
temperature             1982-2017 in ice-free regions in summer      12)
                        (high confidence, SROCC-3)

             Antarctic  Warmed in northern areas of Southern         Circumpolar increases (high confidence,
                        Ocean but cooled in its southernmost         WG1-12)
                        regions since the 1980s (high confidence,

Sea-ice cover Arctic    Loss (particularly of multi-year sea-ice) Will become sea-ice free (< 1 x 106 km2)

                        accelerated since 2001 (very likely, WG1- during summer before 2050, irrespective

                        9)                                           of global warming level (likely, WG1-9)

             Antarctic  No significant circumpolar trend from        Circumpolar decrease (low confidence due
                        1979�2018 (very high confidence), but        to limited understanding of driving
                        decrease off the Antarctic Peninsula (high   processes, WG1-9)
                        confidence) and increases and decreases in
                        other regions (medium confidence, WG1-

Ocean surface Both      Decrease since 1980 at rates of 0.003�       Further acidification by 0.1�0.6 pH by
                        0.026 pH units per decade in open polar      2100 (Atlas), characterized by year-
pH           Poles      zones (very likely, WG1-12)                  around conditions corrosive for aragonite
                                                                     minerals by 2100 (very likely, SROCC-3)

Terrestrial, freshwater and ice

Atmospheric Arctic      Increase of means higher than twice global Further increase (Table SMCCP6.1)
Temperature             mean, most pronounced in cold season
                        (high confidence, WG1-12)

             Antarctic  Warmed from 1957�2016 at 0.2�0.3癈 per       Region: Future warming across
                        decade in W. Antarctica (very likely); No    continent (high confidence, WG1-12)
                        consistent change in E. Antarctica (limited
                        evidence, WG1-12)

Extreme      Arctic     Increase since 1979 (WG1-12)                 Polar amplification will drive further
                                                                     increases (high confidence, WG1-12)
Heat Events

             Antarctic  Heatwave across Antarctica (2020) (WG1-      Further increase, with > 50 additional
                        12, (Robinson et al., 2020).                 days above freezing by 2100 (under
                                                                     RCP8.5, vs. 2014) over the Antarctic
                                                                     Peninsula but smaller changes over
                                                                     mainland Antarctica (medium
                                                                     confidence, WG1-12)

Fire Weather Arctic     Over 4 decades, fire season lengthened and FW index increases and more frequent
                        number of fires increased in N America       fires in tundra regions (high confidence,

                        (WG1-12)                                     WG1-12)

Precipitation Arctic    Increase, highest during the cold season
                        (likely, Atlas)

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             Antarctic  Increasing trend over the 20th century,
                        while large interannual variability masks
                        any existing trend since the end of 1970
                        (medium confidence, Atlas)

Floods       Arctic     Increasing river runoff, increasing heavy    Further increases in all variables (high
                        precipitation (high confidence, WG1-12)      confidence, WG1-12)

Snowfall     Arctic     Recent overall declines in snow extent and Higher % of precipitation as rain (fall
                        seasonal duration (high confidence, WG1- and spring) (high confidence, WG1-12)

             Antarctic  Increases in the 20th century (medium        Further increases (over land) (likely,
                        confidence, WG1-12)                          WG1-12)

Glaciers and Arctic     Losses in glacier mass since 2000 (high      Further mass loss until 2100 under all
Ice Sheets              confidence, WG1-12); Losses in Greenland     warming scenarios (virtually certain,
(IS)                    IS mass since 1980 at increasing rates       WG1-9 and -12)
                        (high confidence, WG1-9)

             Antarctic  Losses in glacier mass since 2000 (high      Further mass loss until 2100 under all
                        confidence, WG1-12); Losses in Antarctic     warming scenarios (likely, WG1-9 and -
                        IS mass since 1992 (in W Antarctica but      12)
                        also parts of E Antarctica since 2000)
                        (high confidence, WG1-9)

Permafrost Arctic       Rising permafrost temperatures over past     Increases in temperature and active
                        3-4 decades (high confidence, WG1-9);        layer thickness (WG1-9); Near-surface
                        Decreases in permafrost active layer         terrestrial permafrost extent will reduce
                        thickness (very high confidence)             under all scenarios by 2100 (virtually
                        (Biskaborn et al., 2019). Submarine          certain, WG1-9)
                        permafrost warming (medium confidence,

             Antarctic Rising permafrost temperatures over past
                              3-4 decades (high confidence, WG1-9).

Lake, River Arctic      Declines in seasonal lake ice cover          Many lakes will lose > 1 month lake ice
Ice                     thickness and duration over most Arctic      cover by 2050 (medium confidence),
                        lakes; Declines in cold-season river ice     Reductions in average Northern
                        extent (high confidence, WG1-12)             Hemisphere seasonal river ice duration
                                                                     of 6.10 days per 1癈 GWL (WG1-12)

Coastal      Arctic     Increase (medium confidence, WG1-12)         Further increase (high agreement-
floods /                                                             limited evidence, WG1-12)

                            Antarctic (Lack of studies, WG1-12)


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2 Figure CCP6.2: Observed and projected climate changes across the Arctic (A, C-H) and Antarctic (B, I-N). Boundary

3 lines in each plot are based on the polar regions defined in Figure CCP6.1. All data shown here are extracted from the

4 IPCC WGI Interactive Atlas (Guti閞rez et al., 2021; Iturbide et al., 2021); data set details can be found in the Atlas

5 ( Arctic (A) and Antarctic (B) are observed temperature trends (癈/decade) over land

6 for the period 1980-2015, derived from ERA5 adjusted dataset. Projected changes from an ensemble of CMIP6

7 projections: annual mean temperature over land is depicted for 2癈 (C, I) and 4癈 (F, L). Global Warming Levels

8 (GWL) in the Arctic and Antarctic, respectively; annual mean sea surface temperature is depicted for 2癈 (D, J) and

9 4癈 (G, M) GWL in the Arctic and Antarctic respectively; annual sea-ice (%) is depicted for 2癈 (E, K) and 4癈 (H, N)

10 GWL in the Arctic and Antarctic, respectively.



13 CCP6.2        Observed Impacts and Future Risks



16 Table CCP6.2: Summary of observed impacts (and projected risks of climate change for polar marine, terrestrial and

17 freshwater ecosystems identified in Section 3.2.3 and Box 3.4 in Chapter 3 of the IPCC SROCC (Meredith et al., 2019).

    Affected system           Hazard               Observed impacts, future risks and natural adaptations

                              *Cascading Effect identified in SROCC (Confidence Level)

    Arctic marine ecosystems

    Primary Producers         Sea-ice loss         Impact: Timing (earlier and later blooms), distribution and
    (PP-1)                    * Freshening         magnitude (>30% increase in annual net primary production
                              * Stratification     since 1998) (high confidence)

                              Acidification        Adaptation: phytoplankton may compensate for decrease pH

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Zooplankton       * PP-1                       Impact: Changing production and community composition
Benthos                                        (medium confidence)
                  * PP-1
Fish                                           Impact: Changing production and biodiversity (medium
                  Acidification                confidence)

                  Warming                      Risk: Effects on zooplankton and pteropods depends on climate
                  * Prey changes               scenario and species' sensitivity/adaptive capacity

                  * Prey declines              Impact: Northward expanding ranges of sub-Arctic/boreal
                                               species (e.g., Atlantic cod) in Bering Sea (Detection - high
Birds and Marine  Sea-ice loss                 confidence, Attribution - medium confidence) negatively
Mammals                                        affecting Arctic polar cod (medium confidence)

Polar Bears       Sea-ice timing,              Risk: Decreasing production of walleye pollock, Pacific cod and
                  distribution,                arrowtooth flounder, due to declines in large copepods (medium
                  thickness                    confidence)

Antarctic marine ecosystems                    Impact: Phenological, behavioural, physiological, and
                                               distributional changes; Endemic marine mammals have little
Primary Productivity Sea-ice loss              scope to move northwards in response to warming (high
                             * Freshening      confidence)
                             * Stratification
                                               Impact: Phenological shifts, and changes in distribution, denning,
Microbes          Acidification                foraging behaviour and survival rates (high confidence)

Antarctic Krill   Warming                      Impact: Little overall change in biomass at circumpolar scale
                                               from 1998�2006, but sub-regional differences (medium
Zooplankton       Acidification                confidence); Changes difficult to detect and attribute to climate
Benthos           Sea-ice loss                 change.
                  Sea-ice loss
                                               Impact: Detrimental effect on primary production and changes to
Fish              Warming                      the structure and function of microbial communities (medium

                                               Impact: Declines in abundance in the South Atlantic sector
                                               (medium confidence); May not represent a long-term, climate-
                                               driven trend but a decline following a period of anomalous peak
                                               abundance (low confidence)

                                               Risk: Southward range shift due to changes in the location of the
                                               optimum conditions for growth and recruitment, with decreases
                                               most apparent in the areas with the most rapid warming, such as
                                               the southwest Atlantic/Weddell Sea region (medium confidence)

                                               Risk: Vulnerability of pteropods through effects on eggs
                                               (medium confidence)

                                               Risk: Increase of biomass on the Antarctic continental shelf as
                                               productivity from longer phytoplankton blooms outweigh ice-
                                               scour mortality (low confidence)

                                               Risk: Shallow-water communities may become dominated by
                                               macroalgae due to increases in the amount of light (possible loss
                                               of endemic species by 12% due to warming temperatures) (low

                                               Risk: Icefish may be displaced from shallow regions around sub-
                                               Antarctic islands (low confidence)

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Birds and Marine    Sea-ice cover                Impact: Predictability of foraging grounds and sea-ice cover
Mammals                                          associated with climate are main drivers of population changes:
                                                 Increases for gentoo penguins (decreases for Ad閘ie, chinstrap,
                                                 king and Emperor penguins) (high confidence)

Arctic terrestrial and freshwater ecosystems

Vegetation          Warming                      Impact: Greening (high confidence)

                                                 Risk: Decrease tundra areal extent >50% by 2050; wood shrubs
                                                 expected to increase (medium confidence)

Vertebrates         Warming                      Impact: Expanding range into Arctic

Freshwater Primary  * Increased runoff           Impact: Increased productivity in rivers, lakes and coastal areas
Productivity        * Increased
                    permafrost thaw

                                                 Risk: Expected to mobilise stores of pollutants

Pathogens           Warming                      Impact: Expanding range into Arctic

                                                 Risk: Mobilisation may increase in high latitudes, including
                                                 anthrax from frozen carcasses possibly released from permafrost

Fish                * Freshwater winter Risk: Disruption of the life history of Arctic freshwater fish


                    * Increased


                    * Warming                    Risk: May make some surface waters inhospitably warm for cold
                    freshwater                   water fish species

Biodiversity        Warming                      Impact: Subarctic biodiversity expanding into Arctic

Reindeer/ Caribou Climate factors                Impact: Reindeer/caribou declined overall without adaptation
                                                 (high confidence), with climate affecting many aspects of their
                                                 life history (medium confidence)

                                                 Risk: Domesticated reindeer/caribou can be affected by fire,
                                                 which reduces pasture, as well as by increased ice-on-snow,
                                                 which can cause starvation

Antarctic terrestrial and freshwater ecosystems

Terrestrial Biota   * Increased coastal Impact: Increasing coastal ice-free areas available for colonisation

                    ice melt                     (high confidence)

Alien Species       Warming                      Risk: Barriers to alien species reduce, affecting terrestrial
                                                 biodiversity (medium confidence)

 3 CCP6.2.1 Marine and Coastal Ecosystems
 6 CCP6.2.1.1 Warming and sea-ice retreat cause shifts in distribution ranges of species
 8 In Arctic seas, warming and other climate impact drivers, primarily sea-ice retreat, have led to range
 9 contractions of Arctic marine and ice-associated species and poleward expansions of boreal species (very
10 high confidence) (Table CCP6.2) (Bouchard and Fortier, 2020; Huntington et al., 2020; Mueter et al., 2020)
11 even though light and energetics at seasonal extremes may limit some range shifts (limited evidence)
12 (Ljungstr鰉 et al., 2021). Altered conditions allow more microorganisms to move poleward and provide
13 opportunities for invasive species (Cavicchioli et al., 2019; Nielsen et al., 2020; Mustonen, 2021).

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 1 Phytoplankton communities harbour increasing numbers of taxa, including harmful species (Lovejoy et al.,
 2 2017) and the coccolithophore Emiliania huxleyi, which meanwhile forms regular blooms in the Barents Sea
 3 (Neukermans et al., 2018; Silkin et al., 2020). Northward shifts of pelagic, benthic and demersal species and
 4 subsequent changes in Arctic community composition have been observed in the Bering, Greenland and
 5 Barents Seas (Grebmeier et al., 2018; Mueter et al., 2020), as have higher numbers of economically
 6 important boreal species such as haddock and Pacific and Atlantic cod (CCP6.2.3). Cold-adapted Arctic fish
 7 species such as polar cod (Boreogadus saida) are expected to decline further and lose spawning habitats at
 8 global warming levels >1.5 癈, mainly due to a lack of phenotypic plasticity, as well as increasing
 9 interspecific competition with and predation from invading boreal species (Dahlke et al., 2018; Marsh and
10 Mueter, 2020). Numerous mammals and seabirds respond to changes in the distribution of their preferred
11 habitats and prey by shifting their range, altering the timing or pathways for migration or switching prey
12 (very high confidence) (Hamilton et al., 2017; Loseto et al., 2018; Meredith et al., 2019). Ice-breeding seals
13 (e.g., harp seals - Pagophilus groenlandicus) often have little scope to shift distribution, leading to increases
14 in strandings and pup mortality in years with little ice cover (medium confidence) (Table CCP6.2) (Boveng
15 et al., 2020). Recent studies confirm that polar bears (Ursus maritimus) are negatively affected by changing
16 ice and snow conditions with decreases in denning, foraging, reproduction, genetic diversity and survival
17 rates (very high confidence) (Table CCP6.2) (Boonstra et al., 2020; Johnson and Derocher, 2020; Maduna et
18 al., 2021).
20 In the Southern Ocean, southward range shifts are expected to result from increased warming coupled with
21 the narrow thermal tolerance of cold-adapted Antarctic species (Convey and Peck, 2019; Morley et al., 2019;
22 Gutt et al., 2021). Such shifts have so far only been detected for Antarctic krill (Euphausia superba), with a
23 poleward contraction of the highest densities of krill in the Atlantic sector (medium confidence) (Table
24 CCP6.2); (Atkinson et al., 2019). Ocean warming is expected to put pressure on Antarctic phytoplankton
25 (Pinkerton et al., 2021) and fish species unable to move further south in shelf areas, including waters off sub-
26 Antarctic islands (low confidence) (Table CCP6.2) (Caccavo et al., 2021). Off the Antarctic Peninsula and
27 sub-Antarctic islands, invasive benthic invertebrates and macroalgae have already been detected (medium
28 confidence) (Fraser et al., 2018; Avila et al., 2020; Brasier et al., 2021), and projected changes will further
29 favour the spread of invasive species (Fraser et al., 2020; Macaya et al., 2020). On a local to regional scale,
30 the benthic recolonization of the newly exposed seabed after the disintegration of ice shelves shows typical
31 succession patterns, with mass occurrences of few pioneer species followed by gradual shifts to a more
32 diverse typical shelf community, driven by increasing pelagic primary production upon ice-shelf collapse
33 and strengthening of the pelagic-benthic coupling (high confidence) (Brasier et al., 2021; Gutt et al., 2021).
34 Range changes of Antarctic birds and marine mammals have been observed, which vary among sub-regions
35 and are mostly attributable to changes in sea-ice extent and food availability (high confidence) (Table
36 CCP6.2) (Gutt et al., 2018; Convey and Peck, 2019; Bestley et al., 2020). With projected sea-ice retreat and
37 associated change in prey distribution (Henley et al., 2020), foraging areas of sub-Antarctic seabirds and
38 marine mammals will shift southwards, leading to elevated pressure on populations due to higher foraging
39 costs during the breeding season (medium confidence) (Ropert-Coudert et al., 2018; Bestley et al., 2020;
40 Hindell et al., 2020; H點kst鋎t et al., 2020; Wege et al., 2021). These changes are particularly impacting
41 emperor penguins (Aptenodytes forsteri) (Table CCP6.2), with the projected population declining close to
42 extinction by 2100 under business-as-usual climate scenarios (medium confidence) (Jenouvrier et al., 2020;
43 Trathan et al., 2020; Jenouvrier et al., 2021), whereas population decline is halted by 2060 under the 1.5癈
44 climate scenario (low confidence) (Jenouvrier et al., 2020).
46 CCP6.2.1.2 Ocean warming and sea-ice changes affect marine primary productivity
48 In the central Arctic Ocean, primary productivity remains low (medium confidence), mostly due to persisting
49 nutrient and light limitations (Randelhoff and Guthrie, 2016; Ardyna and Arrigo, 2020). In inflowing
50 (Barents and Chukchi Sea) and interior shelf regions (Laptev, Kara, and Siberian Sea), changes in sea-ice
51 extent, thickness and seasonal timing have altered light and mixing regimes, causing increasing overall
52 productivity in open-water and under-ice habitats, and in leads (high confidence) (Table CCP6.2) (Ardyna
53 and Arrigo, 2020; Lannuzel et al., 2020). Productivity changes are associated with the earlier onset
54 phytoplankton spring blooms and the increasing occurrence of autumn blooms, particularly at lower latitudes
55 of the Arctic (high confidence) (Table CCP6.2) (Tedesco et al., 2019; Ardyna et al., 2020). Ice algal
56 communities are expected to change in productivity and species composition in response to the transition
57 from a predominantly multi-year to a seasonal sea-ice pack (high confidence) (Meredith et al., 2019; Tedesco

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 1 et al., 2019; Lannuzel et al., 2020). Thinner sea-ice increases the likelihood of surface flooding, resulting in
 2 the occurrence of snow-infiltration algal communities, which have been described in the Atlantic sector of
 3 the Arctic Ocean (Fern醤dez-M閚dez et al., 2018) and observed by Indigenous Peoples off northern
 4 Greenland (Box CCP6.2). The observed transition from marine-terminating to land-terminating glaciers has
 5 a negative impact on coastal ecosystems in Greenland (medium confidence) (Meire et al., 2017; Hopwood et
 6 al., 2018) and Svalbard (Halbach et al., 2019), as land-terminating glacial meltwater input increases
 7 stratification, which hinders vertical mixing and lowers local productivity, whereas marine-terminating
 8 glaciers can trigger upwelling, which supplies nutrients and enables higher productivity in the summer
 9 (Hopwood et al., 2020). Macroalgae and seagrass are generally expanding in the Arctic (medium
10 confidence), though there are negative trends in some regions, partly due to increased runoff and turbidity
11 from melting glaciers (Hopwood et al., 2020; Krause-Jensen et al., 2020). In the future Arctic Ocean, higher
12 light availability in response to further sea-ice decline and reduced deep mixing is projected to generally
13 increase primary productivity (medium confidence), leading to an increase in phytoplankton biomass from
14 2000-2100 by ~20% for SSP1-2.6 and ~30-40% for SSP5-8.5 (Chapter 3) (Kwiatkowski et al., 2020).
15 However, productivity may increase less than predicted and eventually even decrease once nutrient
16 limitation outweighs the benefits of higher light availability (low confidence) (Randelhoff et al., 2020;
17 Seifert et al., 2020).
19 Despite large-scale environmental changes in the Southern Ocean, such as the deepening of the summer
20 mixed layer (medium confidence) (Panassa et al., 2018; Sall閑 et al., 2021), and the expected impacts via
21 altered nutrient entrainment, light availability and grazer encounter rates (Chapter 3) (Behrenfeld and Boss,
22 2014; Llort et al., 2019), assessments indicated no consistent changes in primary production at the
23 circumpolar scale, as sectors and regions show different trends (medium confidence). Although a global
24 assessment found no overall changes in circumpolar primary production from 1998-2015 (Table CCP6.2)
25 (Gregg and Rousseaux, 2019), another study showed an overall increase in phytoplankton biomass in the
26 mixed layer over the period 1997-2019 (Pinkerton et al., 2021). Primary productivity has increased in the
27 Pacific sector and decreased in the Atlantic sector and the Ross Sea (low confidence) (Kahru et al., 2017;
28 Henley et al., 2020; Pinkerton et al., 2021). Higher productivity has also been observed in regions where
29 rapid environmental changes occurred, such as in the vicinity of retreating ice sheets and declining sea-ice
30 cover off the Antarctic Peninsula (medium confidence) (Henley et al., 2020; Rogers et al., 2020), although
31 diversity of phytoplankton may decrease with warming temperatures and less sea-ice (limited evidence) (Lin
32 et al., 2021). In the future Southern Ocean, stronger upwelling due to strengthened westerly winds is
33 projected to increase primary productivity at the circumpolar scale in the Antarctic Zone and to the north of
34 the sub-Antarctic Front, but not in the sub-Antarctic Zone (low to medium confidence) (Chapter 3) (Henley
35 et al., 2020; Kwiatkowski et al., 2020; Pinkerton et al., 2021). The largest changes are projected to occur
36 after 2100 at 2-6癈 warming of the surface ocean (Moore et al., 2018). Such an increase in Southern Ocean
37 productivity will lead to a decline in global ocean productivity (medium confidence), due to nutrient trapping
38 (Moore et al., 2018) and altered ocean carbon uptake through ecosystem feedbacks (Hauck et al., 2018).
40 CCP6.2.1.3 Impacts of ocean acidification vary spatially and among biotas
42 In Arctic seas, areas with acidification levels corrosive to organisms forming CaCO3 shells or skeletons
43 expanded between the 1990s and 2010 (high confidence), with instances of extreme aragonite under-
44 saturation (Ding et al., 2017; Zhang et al., 2020). Key species of diatom and picoeukaryote phytoplankton
45 species yet appear relatively resilient to decreasing pH levels over a range of temperature and light
46 conditions (medium confidence) (Table CCP6.2) (Thoisen et al., 2015; Wolf et al., 2018; White et al., 2020).
47 In contrast, there is evidence for species- and stage-specific sensitivities of zooplankton, pteropods and
48 fishes (high confidence) (Table CCP6.2) (Bailey et al., 2016; Dahlke et al., 2018; Thor et al., 2018).
49 Warming, rising river-sediment discharge and coastal erosion in Arctic shelf regions are expected to increase
50 the input of labile, often permafrost-derived organic carbon, the remineralisation of which further increases
51 acidification rates (medium confidence) (Semiletov et al., 2016; AMAP, 2018b; Br鰀er et al., 2018).
52 Interactions with other physical changes, such as warming or freshening, are expected to aggravate the
53 impacts of ocean acidification (Chapter 3) (Falkenberg et al., 2018).
55 In the Southern Ocean, calcifying organisms are also most vulnerable to ocean acidification (high
56 confidence) (Table CCP6.2), as evidenced by rates of calcification declining by 3.9% between 1998-2014
57 (Freeman and Lovenduski, 2015). Calcifying species with low-magnesium calcite or mechanisms to protect

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 1 their skeletons are less vulnerable to the corrosive effects of acidification than those using aragonite or high-
 2 magnesium calcite (high confidence) (Figuerola et al., 2021). In diatom-dominated communities,
 3 silicification diminishes with reduced pH levels, albeit with rates differing among taxa (low confidence)
 4 (Petrou et al., 2019). Species-specific responses exist regarding growth and primary production, which are
 5 further strongly modulated by iron and light availability (high confidence) (Hoppe et al., 2013; Trimborn et
 6 al., 2013; Hoppe et al., 2015; Henley et al., 2020; Seifert et al., 2020). A meta-analysis yielded different CO2
 7 thresholds for Antarctic organismal groups, e.g., negative impacts emerged at >1,000 atm CO2 in
 8 phytoplankton and at >1,500 atm CO2 in invertebrates, whereas bacterial abundance was positively affected
 9 by ocean acidification (Hancock et al., 2020). Species sensitivity can also differ strongly between life-cycle
10 stages (Chapter 3.3.2). For instance, eggs and embryos of Antarctic krill are negatively impacted at >1,250
11 atm CO2 whereas adults can thrive even at 1,000-2,000 礱tm CO2 over one year (Kawaguchi et al., 2013;
12 Ericson et al., 2018).
14 CCP6.2.1.4 Climate change alters food web dynamics
16 Climate change has transformed Arctic marine ecosystems from sea-ice-associated to open-water production
17 regimes, with profound impacts on trophic energy transfer efficiencies and pathways (high confidence)
18 (Behrenfeld et al., 2017; Meredith et al., 2019; Huntington et al., 2020) as well as benthic-pelagic coupling
19 (medium confidence) (Birchenough et al., 2015; Degen et al., 2016; Solan et al., 2020). Shifts in bloom
20 phenology favour small phytoplankton and smaller zooplankton over large lipid-rich macro-zooplankton,
21 leading to longer, less efficient food chains (medium confidence) (Aarflot et al., 2018; Feng et al., 2018;
22 Kimmel et al., 2018; Weydmann et al., 2018; M鴏ler and Nielsen, 2020). In the Beaufort Sea and Svalbard
23 waters, earlier spring phytoplankton blooms have resulted in a mismatch in dynamics between microalgae
24 and herbivorous copepods (Renaud et al., 2018; Dezutter et al., 2019). In the Bering Sea, zooplankton
25 declines following the particularly pronounced sea-ice retreats in 2017 and 2018 were associated with
26 reduced forage fish production (Duffy-Anderson et al., 2019), as well as multitrophic mortality of
27 ctenophore, fish, bird, and mammal species, coupled with severe emaciation, reproductive failure, disease,
28 and high mortality rates of seabird predators (Section (Jones et al., 2019; Maekakuchi et al., 2020;
29 Piatt et al., 2020; Romano et al., 2020). Species range shifts have restructured higher trophic levels in Arctic
30 food webs (high confidence) (Table CCP6.2; CCP6.2.3.3 Chapter 3) (Huntington et al., 2020). In the
31 northern Barents Sea, increased predation mortality for key species and incursions of boreal fish have
32 induced entire ecosystem reorganization (Degen et al., 2016; Pecuchet et al., 2020a; Pecuchet et al., 2020b).
33 Regional taxonomic and functional diversity increased with immigration of boreal species, although the
34 ongoing decline in Arctic species suggests high species turnover (Table CCP6.2) (Frainer et al., 2017).
35 Recent marine heatwaves induced rapid and profound food web changes unprecedented over the last four
36 decades (Siddon et al., 2020).
38 Climate impacts on Arctic marine food webs will be profound and intensify with global warming levels
39 (high confidence), regardless of mitigation scenarios due to multidecadal lags in sea-ice extent and
40 atmospheric carbon (WGI) (Jones et al., 2020). However, the exact nature of these impacts remains unclear
41 due to attenuating and amplifying dynamics of both top-down and bottom-up processes in polar food webs
42 and the management of fisheries (high confidence) (Chapter 3) (Cavicchioli et al., 2019; Meredith et al.,
43 2019). Projected sea-ice loss is associated with a >50% decline in the density of large zooplankton species
44 by 2100 (relative to early 21st century levels) in the southern Bering Sea and a net increase in large
45 zooplankton in the northern Bering Sea in scenarios without carbon mitigation (RCP8.5), whereas these
46 declines are roughly half the magnitude under moderate mitigation scenarios (RCP4.5) (Hermann et al.,
47 2019; Kearney et al., 2020). Warming is expected to reduce the quantity and quality of lipid-rich copepod
48 prey (high confidence) (Aarflot et al., 2018; Kimmel et al., 2018; Bouchard and Fortier, 2020; M鴏ler and
49 Nielsen, 2020; Mueter et al., 2020), leading to declines in survival and growth of multiple upper-trophic
50 level fish species; these impacts are amplified over time under low mitigation scenarios (RCP8.5) (high
51 confidence) (CCP6.2.1.1) (Dahlke et al., 2018; Holsman et al., 2020; Mueter et al., 2020; Oke et al., 2020;
52 Reum et al., 2020; Thorson et al., 2020; Whitehouse et al., 2021). Marine mammals and seabirds will
53 continue to attenuate climate change impacts by shifting their diets and behaviour (medium confidence)
54 (Table CCP6.2) (Hamilton et al., 2017; Lowther et al., 2017; Lydersen et al., 2017; Vihtakari et al., 2018;
55 Boveng et al., 2020). However, seabirds generally have low temperature-mediated plasticity of reproductive
56 timing, making them vulnerable to mismatches with their prey and limiting long-term adaptation (medium

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FINAL DRAFT                       Cross-Chapter Paper 6  IPCC WGII Sixth Assessment Report

 1 confidence) (Keogan et al., 2018; Kharouba and Wolkovich, 2020; Piatt et al., 2020; Samplonius et al.,
 2 2021).
 4 Many factors have contributed to changes in Antarctic food webs, including historical exploitation of fish
 5 and marine mammals as well as changes driven by the ozone hole and climate factors (Meredith et al., 2019;
 6 Morley et al., 2020; Grant et al., 2021). Most documented changes resulting from warming and sea-ice losses
 7 relate to shifts in ranges and dynamics of species, with most impacts occurring around the Antarctic
 8 Peninsula (CCP6.2.1.1; Table CCP6.2).
10 The projected general rise in primary production in Antarctic seas by 2100 (CCP6.2.1.2) suggests a
11 concomitant increase in the abundance of higher trophic species, but changes in the structure and function of
12 food webs will vary (McCormack et al., 2021; McCormack, accepted) depending on regional differences in
13 changing drivers (Morley et al., 2020; Cavanagh et al., 2021; Grant et al., 2021). Primary production in open
14 water habitats is expected to be supported by smaller phytoplankton species in the future (Henley et al.,
15 2020), which could increase the relative importance of the copepod-mesopelagic fish pathway (McCormack,
16 accepted), because krill prefer larger diatoms as food (Siegel, 2016). The optimum habitat for Antarctic krill
17 is expected to decline with a shortening of suitable season for krill growth and reproduction, particularly in
18 the northern Scotia and Bellingshausen Seas (medium confidence) (Veytia et al., 2020), although changes
19 may be difficult to distinguish from natural variability until later in the century (Sylvester et al., 2021). More
20 subtle and unpredictable changes may occur in the structure and relative importance of energy pathways in
21 the food webs (Trebilco et al., 2020). Small mesopelagic fish are increasingly recognized for their
22 importance as mid-trophic level species in the Southern Ocean, particularly in the sub-Antarctic zone
23 (Caccavo et al., 2021) and Central Indian Sector (Subramaniam et al., 2020; McCormack et al., 2021).
24 Although salps have long been considered to be competitors of Antarctic krill (Suprenand and Ainsworth,
25 2017; Rogers et al., 2020), they provide a third energy pathway in pelagic food webs, and, given the
26 changing ocean conditions and their preference for smaller phytoplankton, may increase in importance for
27 copepods (low confidence) (Plum et al., 2020; Trebilco et al., 2020; McCormack et al., 2021; Pauli et al.,
28 2021; McCormack, accepted). Declining ice shelves, such as those off the Antarctic Peninsula, will open up
29 new pelagic and benthic habitats (CCP6.2.1.1) with expected increases in productivity of benthic
30 assemblages in the new areas (Barnes, 2017; Morley et al., 2020; Brasier et al., 2021; Gutt et al., 2021).
32 CCP6.2.2 Terrestrial and Freshwater Ecosystems
34 Since the publication of AR5 (IPCC, 2014) and SROCC (IPCC, 2019) and their findings (Table CCP6.2),
35 more studies confirm rapid changes in Arctic terrestrial and freshwater systems including increased
36 permafrost thaw, changes to tundra hydrology and vegetation (overall greening of the tundra, regional
37 browning of tundra and boreal forests), coastal and riverbank erosion (high confidence) (Canadell et al.,
38 2021; Mustonen and Shadrin, 2021), reduced duration of snow cover and river and lake ice, increased rain-
39 on-snow events, and reduced land-ice extent and thickness (Bieniek et al., 2018; Brown et al., 2018).
40 Climate change continues to alter vegetation and attendant biodiversity, with divergent regional trends across
41 the Arctic due to disparities in local conditions and changes in growing seasons (Zhu et al., 2016; Taylor et
42 al., 2020). Warming facilitates woody vegetation growth in northeastern Siberia, western Alaska, and
43 northern Quebec (Song et al., 2018; Garc韆 Criado et al., 2020), as well as a northward expansion of shrub
44 vegetation and sub-Arctic and boreal species (Davidson et al., 2020).
46 Further evidence shows that warming and changes to the Arctic hydrologic cycle increase the risk of wildfire
47 (medium confidence) (Mustonen and Shadrin, 2021). Both the frequency of and the area burned by wildfires
48 during recent years are unprecedented compared to the last 10,000 years (high confidence) (Meredith et al.,
49 2019; Irannezhad et al., 2020). Fire risk levels are projected to increase across most tundra and boreal
50 regions, and interactions between climate and shifting vegetation (Song et al., 2018) will influence future fire
51 intensity and frequency (medium confidence) (Curtis et al., 2018).
53 For all warming scenarios, declines in snow cover in the Arctic by 2050 (Table CCP6.1) may accelerate

54 vascular plant, moss, and lichen extinction rates (32% for Arctic璦lpine and 12% for boreal species),
55 especially after the tipping point of 20-30% decrease in snow cover duration is passed (Niittynen et al.,
56 2018). Even though the overall regional water cycle will intensify, including increased precipitation,
57 evapotranspiration and river discharge to the Arctic Ocean (Table CCP6.1), snow and permafrost decline

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 1 may lead to further soil drying (medium confidence) (Meredith et al., 2019). Glacial ice melt poses a risk to
 2 ecosystems and people through remobilization of sequestered hazardous waste and transported pollutants
 3 (Table CCP6.3) (Wang et al., 2019).
 5 In the Antarctic, there is further high agreement since the publication of SROCC that melt and ice-free areas
 6 are causing increases in the rates of colonisation and utilization of coastal environments by terrestrial biota
 7 and land-based colonies of seals and birds (Gutt et al., 2021), although colonisation rates remain variable
 8 (Ruiz-Fernandez et al., 2017; Bokhorst et al., 2021). Soil temperatures along the Antarctic Peninsula are now
 9 sufficient for germination of non-native plants; invasions by non-endemic species are expected to increase
10 with rising temperatures (high confidence) (Bokhorst et al., 2021), posing a risk to endemic polar species
11 (medium confidence) (Chown and Brooks, 2019; Gutt et al., 2021).
13 Vegetation responses to warming are contingent on water availability and local temperature (medium
14 confidence) (Guglielmin et al., 2014; Royles and Griffiths, 2015; Amesbury et al., 2017; Cannone et al.,
15 2017; Charman et al., 2018; Robinson et al., 2018; Stelling et al., 2018), which vary greatly around
16 Antarctica (Figure CCP6.1) (Turner et al., 2020a). Antarctic terrestrial ecosystem responses to changes in
17 water availability are not homogeneous (Ball and Levy, 2015; Sadowsky et al., 2016; Fuentes-Lillo et al.,
18 2017; Gooseff et al., 2017; Schroeter et al., 2017; Lee et al., 2018). West Antarctica is showing evidence of
19 greening in the dominant cryptogrammic vegetation, with greater growth in mosses (high confidence)
20 (Casanova-Katny et al., 2016; Amesbury et al., 2017; Shortlidge et al., 2017; Charman et al., 2018; Prather et
21 al., 2019). Peatland ecosystems may increase on the west Antarctic Peninsula with future warming (low
22 confidence) (Yu et al., 2016; Loisel et al., 2017). In contrast, some parts of East Antarctica and the
23 subantarctic islands to the north have been experiencing a drying climate, with declining health of mosses
24 and other vegetation (high confidence) (Bergstrom et al., 2015; Bramley-Alves et al., 2015; Robinson et al.,
25 2018; Bergstrom et al., 2021).
27 Antarctica encountered its first reported heatwave in 2020 (Table CCP6.1). Such abrupt heating can cause
28 wide-ranging effects on biota, from flash-flooding damage and dislodgement of plants to excess melt waters
29 supplying moisture to arid Antarctic ecosystems. This suggests that increased melt may reverse the drying
30 trend if plant communities remain connected to melt streams and there is sufficient precipitation (high
31 agreement, limited evidence) (Bergstrom et al., 2021).
33 Warming of the Antarctic Peninsula has resulted in increased soil microbial abundance and biomass.
34 However this trend is not as great in southern colder locations (medium confidence) (e.g., Kim et al., 2018;
35 Newsham et al., 2019), as the microbial community structure is affected by vegetation cover and water
36 availability (high confidence) (Dennis et al., 2019; Newsham et al., 2019).
38 Antarctic terrestrial invertebrate communities on the West Antarctic Peninsula may be controlled more by
39 vegetation and water availability than by air temperature (medium confidence) (Bokhorst and Convey, 2016;
40 Knox et al., 2016; Andriuzzi et al., 2018; Prather et al., 2019; Newsham et al., 2020). Evidence from
41 laboratory studies, field programs and sedimentary records indicate that Antarctic freshwater ecosystems
42 may become more productive under climate warming scenarios (medium confidence) (e.g., Schiaffino et al.,
43 2011; Borghini et al., 2016; P韘kov� et al., 2019; Cejka et al., 2020).

46 CCP6.2.3 Food, Fiber, and other Ecosystem Products
48 Food and fiber production underpins regional identities, cultures, and communities of practice and place in
49 polar regions, are vital to local and distant economies (Table CCP6.4) and they represent for fisheries a
50 critical source of global nutrition and food security (Hicks et al., 2019). Since SROCC, there is further
51 evidence that climate change alterations of polar ecosystems increasingly challenge production of, and
52 access to, sufficient, healthy, and nutritious food, posing risks to future food and nutritional security within
53 and beyond polar regions (high confidence).
55 CCP6.2.3.1 Arctic subsistence resources

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    FINAL DRAFT                       Cross-Chapter Paper 6                           IPCC WGII Sixth Assessment Report

1 Subsistence harvest of fish, seabirds, and marine mammals is the basis for economic, cultural and spiritual

2 connections with Arctic marine systems (Box CCP6.2)(Fall et al., 2013; Haynie and Huntington, 2016;

3 Raymond-Yakoubian et al., 2017; Slats et al., 2019) and nature-based livelihoods (e.g., caribou and reindeer

4 (Rangifer tarandus) herding, fishing, hunting, trapping, small-scale forestry) are fundamental to Indigenous

5 Peoples across the Arctic as they have been for millennia (Koivurova et al., 2015; Betts, 2016; Gavin et al.,

6 2018; Raheem, 2018; Mustonen and Shadrin, 2021). Climate change has impacted Indigenous subsistence

7 resources across the Arctic (very high confidence) (SMCCP6.2), and future food systems and ecological

8 connections are at risk from future climate change hazards interacting with non-climate pressures, some of

9 which are mediated or amplified by novel conditions and opportunities in Arctic regions (high confidence)

10 (Moerlein and Carothers, 2012; Fall et al., 2013; Raymond-Yakoubian et al., 2017; Meredith et al., 2019;

11 Slats et al., 2019; Huntington et al., 2020; Huntington et al., 2021). Increasing heatwaves, wildfires, extreme

12 precipitation, permafrost loss and rapid seasonal snow and ice thaw events will further threaten terrestrial

13 subsistence food resources across the Arctic (high confidence) (Table CCP6.3). Although climate impacts

14 and non-climate factors systematically undermine access to and productivity of subsistence resources,

15 resilience is inherently high for Indigenous Peoples, illustrating critical elements underpinning successful

16 adaptation to climate change (Box CCP6.2) (Huntington et al., 2021).


19 Table CCP6.3: Illustrative examples of climate change impacts on subsistence resources in the Arctic.

    Changing         Observed impacts and projected risks                                 References


    Snow, ice, river Climate change is disrupting subsistence harvests for Indigenous (Wildcat, 2013; Meredith et al.,
    environments Peoples in Arctic communities that depend on snow, ice and river 2019; Slats et al., 2019)

                           environments for travel and access to subsistence resources.

    Multiple         Across the Canadian Arctic, multiple populations of reindeer and (Russell et al., 2018)
                     caribou are in decline with 95% of assessed herds listed as rare,
                     decreasing or "threatened"; Reindeer and caribou abundances in
                     the Alaska-Canada region have declined 56% over the past 20

    Multiple         Reindeer herding is an important economic and Indigenous             (Furberg et al., 2011; Uboni et

                     cultural activity in the Eurasian Arctic and is being affected by al., 2020; Mustonen and

                     non-climate and climate events, including changes to thaw            Shadrin, 2021)

                     cycles, drought and unpredictable summer weather, which

                     threaten pasture areas in Siberia. Although changes in vegetation

                     and the freeze thaw cycle are impacting Sami reindeer herding,

                     adaptive measures by herders have been effective at offsetting

                     multiple climate and non- climate impacts.

    Sea-ice; winds;  Loss of multiyear "mother ice", declines in seasonal sea-ice         (Stephenson and Smith, 2015;
    visibility       thickness and stability, as well as changes in winds and visibility  Brinkman et al., 2016; Melia et
                     have impacted the availability of, and access to, subsistence        al., 2016; Raymond-Yakoubian
                     resources (high confidence) and have increased interactions          et al., 2017; Ford et al., 2019;
                     between coastal communities and shipping, tourism and                Slats et al., 2019; Huntington et
                     commercial fisheries, which directly impact human safety and         al., 2020; Huntington et al.,
                     well-being in Arctic communities (high confidence).                  2021)

    Multiple         MHW-induced ecosystem changes contributed to widespread              (Jones et al., 2019; Piatt et al.,
                     mortality events and declines in Northern Bering Sea seabirds        2020; Siddon et al., 2020)
                     and disrupted subsistence harvests in western Alaska.

    Storminess; sea- Although some communities have seen reduced whale harvests (George et al., 2017; Hauser et

    ice; whale       due to climate impacts on survival and productivity, changes in al., 2018; Loseto et al., 2018;

    migration timing; storminess and whale migration timing have lengthened the July Mustonen et al., 2018a)

    shipping         harvest season for Inuvialuit from Inuvik, Aklavik and

                     Tuktoyaktuk. Changes in Beluga migration routes have increased

                     accessibility to communities of Ulukhaktok and Paulatuk. In

                     Western Greenland, loss of sea-ice has both reduced access to

                     sealing and increased subsistence and commercial harvest of

                     Atlantic cod, halibut, and other fish species. Increased impacts of

                     noise and ship strikes associated with shipping are expected to

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                impact subsistence species, especially seals and whales in
                Lancaster sound as well as the Pacific Arctic.

Sea-ice         Changes in sea-ice will continue to undermine subsistence     (Jacobsen et al., 2018; Ford et
                resources and disrupt access by smaller scale commercial and  al., 2019)
                subsistence-based ice-edge fishing.

Shifting        Shifting species distributions and climate change mediated food (Moerlein and Carothers, 2012;
Food web        web reorganization pose a risk to near-shore subsistence harvests Fall et al., 2013; Brinkman et al.,
                that are essential to sustaining Indigenous Peoples in Western 2016; Loseto et al., 2018;

                Greenland and the Northern Bering, Beaufort, and Chukchi Seas; Steiner et al., 2019; Marsh and

                , e.g., cod biomass in the Inuvialuit region is projected to  Mueter, 2020; Ribeiro et al.,

                decrease 17% by 2100 (RCP8.5). Climate-related declines in 2021)

                harvester access drive projected declines in subsistence

                availability in Alaska.

 3 CCP6.2.3.2 Agriculture, forestry, livestock, and aquaculture
 5 In addition to reindeer herding, Arctic agriculture primarily consists of local production of cool season crops,
 6 forage, small grains, and livestock (sheep and goats) (Westergaard-Nielsen et al., 2015; Natcher et al., 2019).
 7 Short growing seasons, cold conditions, permafrost, and moisture stress, especially along coasts, have
 8 historically limited production, but agriculture is generally increasing across the region (Westergaard-
 9 Nielsen et al., 2015). Although only ~ 0.2% of Alaska is farmland, area farmed and income from agriculture
10 have increased 2% and 80% (respectively) since 2012 (United States Department of Agriculture, 2017). It is
11 likely that growing seasons have extended by 1-3 days per decade in interior Alaska, although some coastal
12 areas exhibit declines in growing season (Lader et al., 2018).
14 Arctic temperatures rarely exceed thermal tolerances for crops (e.g., 35-38癈 across corn, rice and grain) and
15 warming will provide new opportunities for food and forage production in areas such as SW Greenland and
16 interior Alaska (Westergaard-Nielsen et al., 2015; Tripathi et al., 2016; Lader et al., 2018). Higher
17 atmospheric CO2 favours plant growth if soil quality and condition are sufficient, but benefits can be offset
18 by increased heat and water stress associated with climate change (Tripathi et al., 2016; Unc et al., 2021).
19 Growing seasons in Alaska will lengthen by 48-87 days per year relative to historical growing season length
20 (1981-2010) and the start of growing season is expected to shift 1-4 weeks earlier (Lader et al., 2018).
21 Feasible growing areas across the Arctic are expected to shift northward and increase within the 55�-69癗
22 region (King et al., 2018). Permafrost thaw (Table CCP6.1) increases drainage, which is a potential benefit,
23 but can also increase erosion, subsidence and irregular surfaces, inhibiting agriculture (Lader et al., 2018).
24 Conversion of Arctic soils to croplands may also release carbon stored in vegetation and soils (Unc et al.,
25 2021).
27 Arctic aquaculture contributes approximately 2% to global farm production (primarily Norwegian salmon
28 (Salmo salar), as well as finfish in Iceland and Sweden and shellfish in Alaska), and will face increasing
29 challenges from climate change (Troell et al., 2017) including increased frequency of storms (impacting sea
30 farms), extreme temperatures, and warmer conditions that favour pathogens, parasites and harmful algal
31 blooms. Aquaculture feeds often depend on small pelagic fish or krill and supply may be affected by climate
32 impacts on fisheries (Table CCP6.6) (Troell et al., 2017; Chen and Tung, 2018; M鴕k鴕e et al., 2020).
33 Integrated policies and coordination across multiple food production sectors in Arctic regions are needed to
34 address climate opportunities and challenges (Altdorff et al., 2021; Unc et al., 2021).
36 CCP6.2.3.3 Commonalities in impacts and risks across polar fisheries
38 Fisheries play an increasingly important role in addressing global food and nutritional deficits (Section
39 3.6.3)(B閚� et al., 2016; Ding et al., 2017; Hicks et al., 2019; Costello et al., 2020), especially as climate
40 change has already reduced global yields from key crops (Myers et al., 2017; Ray et al., 2019; Thiault et al.,
41 2019). Antarctic and Arctic systems support some of the world's largest fisheries, including those for
42 Antarctic krill and Arctic walleye pollock (Gadus chalcogrammus), which constitute a critical source of
43 protein and macronutrients to a growing population of seafood consumers, as well as various aquaculture
44 and livestock feeds (Cross-Chapter Box MOVING PLATE in Chapter 5) (Table CCP6.4) (Huntington et al.,

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1 2013; Raheem, 2018; Hicks et al., 2019; Steiner et al., 2019; FAO, 2020; Cavanagh et al., 2021; Grant et al.,

2 2021; Murphy et al., 2021). Marine sources of protein and nutrition are important in transformational future

3 scenarios where dietary shifts and provisioning policies provide multiple co-benefits to equity, food security

4 and carbon mitigation (Springmann et al., 2016; Poore and Nemecek, 2018; Thiault et al., 2019; Kim et al.,

5 2020). Shifting spatial distributions of fish stocks have led to transboundary management challenges in the

6 Atlantic, Bering Sea, and Arctic areas previously inaccessible due to sea-ice (Table CCP6.6) (Gullestad et

7 al., 2020).


9 Cascading and interacting effects of climate change impacts in polar regions (Table CCP6.1) will reduce

10 access to, and productivity of future fisheries, and pose significant risks to regional and global food and

11 nutritional security that increase with atmospheric carbon levels and declines in sea-ice (high confidence)

12 (Table CCP6.6). Although it is expected that fisheries will continue to contract poleward under future

13 warming (Cross-Chapter Box MOVING PLATE in Chapter 5) (Table CCP6.4) (Alabia et al., 2018; Morley

14 et al., 2018; Stevenson and Lauth, 2019; Caccavo et al., 2021; Grant et al., 2021), global and regional models

15 differ in their projections of fisheries catch potential for the polar regions under climate change. For

16 example, some global-scale models project increases in potential fishery yields in Arctic Canada (Cheung,

17 2018; Bindoff et al., 2019; Tai et al., 2019), whereas many observational studies and high resolution regional

18 projections suggest overall declines in biomass, productivity, and yield associated with warming and loss of

19 sea-ice in multiple regions such as the Bering Sea (medium confidence) (Free et al., 2019; Hollowed et al.,

20 2020; Holsman et al., 2020; Mueter et al., 2020; Reum et al., 2020). Reduced production of macronutrients

21 and protein by polar marine sources will disproportionately impact people already experiencing food and

22 nutritional scarcity (Myers et al., 2017), marine-dependent communities within and beyond polar regions,

23 and women and children who require higher quantities of macronutrients (high confidence).


25 Large-scale commercial fisheries are expected to continue to operate in polar regions (high confidence)

26 (Barange et al., 2018; Cavanagh et al., 2021; Grant et al., 2021), and will shift poleward (high confidence)

27 toward geopolitical and management boundaries (high confidence) (CCP6.3.2.3; Table CCP6.6). Warming

28 and climate impacts will continue to impact transboundary stocks and increase the potential for conflict in

29 fisheries management (Pinsky et al., 2018; Mendenhall et al., 2020; Palacios-Abrantes et al., 2020; Sumaila

30 et al., 2020). Increased distances from ports to redistributed fishing grounds, as well as increased frequency

31 of storms and other extreme events are expected to increase risks and costs for fishery operations (medium

32 confidence) and impact shore-based infrastructure and emergency response services (CCP6.2.4). Observed

33 and expected increases in mobile ice combined with abrupt wind can create major hazards for fish operators

34 in Antarctica and the Arctic, with consequences to human safety and total revenue (Dawson and et al., 2017;

35 Barber et al., 2018; Grant et al., 2021). There will be increased demand for new port infrastructure across the

36 Arctic (high confidence); new ports have already been proposed for the northern Bering Sea, and small craft

37 harbour investments are being considered across Arctic Canada and Greenland. Ecosystem-based

38 management, increasing diversity and flexibility in harvest portfolios, access to high-resolution ecological

39 forecasts and projections, and climate-informed advice will promote adaptation and climate resilience in

40 fisheries (Dawson and et al., 2017; Brooks et al., 2018; Karp et al., 2019; Hollowed et al., 2020). Coupling

41 adaptation measures with global carbon mitigation strategies substantially decreases climate change risks to

42 polar fisheries (very high confidence) (CCP6.3).





47 FAQ CCP6.1: How do changes in ecosystems and human systems in the polar regions impact everyone

48  around the globe? How will changes in polar fisheries impact food security and nutrition around

49  the world?


51 Polar regions are commonly known to be experiencing particularly fast and profound climate change, which

52 strongly affects areas and people all around the world in several ways. Physical processes taking place in

53 these regions are critically important for the global climate and sea level. Less known is that regional

54 climate-driven changes of ecosystems and human communities will also have far-reaching impacts on a

55 number of sectors of human societies at lower latitudes.


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 1 Climate change has triggered rapid, unprecedented, and cascading changes in polar regions that have
 2 profound implications for ecosystems and people globally. Although physically remote from the largest
 3 population centers, polar systems are inextricably linked to the rest of the world through interconnected
 4 ocean currents, atmospheric interactions and weather (IPCC, 2021), ecological and social systems,
 5 commerce, and trade. The nutrient-rich waters of the polar regions fuel some of the most productive marine
 6 ecosystems on earth, which in turn support fisheries for species packed with vital macronutrients that are
 7 essential for human health and wellbeing. The largest most sustainable fisheries in the world are located in
 8 polar waters, where a mix of ice, seasonal light, and cold nutrient-rich waters fuel schools of millions of fish
 9 that swell and retract in numbers across the years, reflecting interlaced cycles of icy cold waters, lipid-rich
10 prey, and abundant predators. Polar systems thus exist in a productive balance that has supported vibrant
11 ecocultural connections between Indigenous Peoples and the Arctic for millennia and has supported global
12 food production and trade for centuries. Climate change increasingly destabilizes this balance with uncertain
13 outcomes for Indigenous Peoples and local residents in the Arctic as well as for the rest of the world.
14 Triggered by warming oceans and air temperatures, accelerated melting of sea-ice, glaciers and ice sheets in
15 polar regions in turn impacts ocean salinity, sea levels, and circulation throughout the global ocean.
16 Warming waters have also pushed cold-adapted species poleward, eroded the cold barrier between boreal
17 and Arctic species, and induced rapid reorganization of polar ecosystems. Studies increasingly indicate that
18 the complex web of physical and biological connections that have fuelled these productive regions will falter
19 without the strong regulating influence of cryospheric change. At the same time the global demand for food
20 is increasing, particularly the demand for highly nutritious marine protein, placing increasing importance on
21 stabilizing polar ecological systems and minimizing climate change impacts and risks.
26 Table CCP6.4: Climate change impacts on Arctic and Antarctic fisheries and fishing communities. Additional detail in
27 Table SMCCP6.3.

Driver            Observed impacts and projected risks                           References

Current and past climate change impacts

Warming           Fisheries productivity declined in multiple stocks across the  (Free et al., 2019; Cheung and
                  Arctic including the EBS while Atlantic cod and other          Fr鰈icher, 2020)
                  fisheries have increased.

Extreme heat      Commercially important fish species declined rapidly during    (Zheng and Ianelli, 2018; Duffy-
                  recent MHWs (2016-2019), in the EBS due to reduced             Anderson et al., 2019; Stabeno et
                  recruitment, increased metabolic demand, and increased         al., 2019; Basyuk and Zuenko,
                  predation mortality and it is probable that climate impacts    2020; Reum et al., 2020;
                  have contributed to the closure of Pribilof islands blue king  Thorson et al., 2020)
                  crab (Paralithodes platypus) fisheries.

Temperature;      In the Barents Sea, northward redistribution of stocks led     (Christiansen et al., 2014;
shifting species  fisheries into previously unfished habitats, exposing benthic  J鴕gensen et al., 2019; Spies et
distributions     ecosystems to novel trawling impacts. Large-scale              al., 2019; Stevenson and Lauth,
                  redistributions of Pacific cod (>1000 km decade-1) and other   2019)
                  groundfish species have challenged fisheries management in
                  the EBS; ~50% of the biomass is now located in the NBS,
                  outside of historical survey areas and in a region where
                  bottom trawling is prohibited (although pelagic gear is

OA, warming,      Shellfish species such as snow crab are undergoing range       (J鴕gensen et al., 2019; Fedewa
winds             contractions poleward in the Barents and Northern Bering       et al., 2020) (Cross-Chapter Box
                  Seas, with increased catches in the north and declines in the  MOVING PLATE in Chapter 5)

Warming;          Poleward expansion of Pacific salmon into Arctic watersheds    (Bilous and Dunmall, 2020;
poleward          and Greenland fjords presents both new opportunities and       Nielsen et al., 2020)
expansion         novel threats to key subsistence and commercial species such
                  as Arctic char and Atlantic salmon.

Warming; HABs Altered seasonal freshwater habitats are impacting salmon (Brattland and Mustonen, 2018;
                      productivity and phenology of important salmon resources in Cline et al., 2019; Mustonen and

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             Alaska and in the Fennoscandian North, with subsequent                   Feodoroff, 2020; Mustonen and

             community-specific impacts on commercial and subsistence Shadrin, 2021)


Multiple; sea-ice Losses of winter sea-ice to the north and west of the Antarctic (Meredith et al., 2019)
                      Peninsula have enabled krill fishing vessels to fish all year
                      round in that area.

Future climate change impacts and risks

Multiple     Climate change impacts on the ecology and physiology of                  (Laurel et al., 2016; Spencer et
             polar cod species contribute to expected increases in biomass            al., 2016; Lotze et al., 2018;
             and catch potential under high to moderate mitigation                    Spencer et al., 2019; Dahlke et
             (RCP2.6 and RCP4.5) and reductions in groundfish                         al., 2020; Gr黶s et al., 2020;
             recruitment and yield under low mitigation (RCP8.5)                      Hollowed et al., 2020; Reum et
             scenarios (CCP6.2.2) across range of multispecies models.                al., 2020; Thorson et al., 2020)

Climate x    Assuming no climate adaptation in current Ecosystem Based                (Holsman et al., 2020; Reum et
management   Management (EBM), 50% declines (relative to projections                  al., 2020; Whitehouse et al.,
interaction  under persistent current climate conditions) in Eastern Bering           2021)
             Sea pollock and cod yield is likely under moderate carbon
             mitigation scenarios (RCP4.5), and very likely under low
             mitigation scenarios (RCP8.5).

Warming; OA  Warming, Ocean Acidification, fish predators, and thermal (Punt et al., 2014; Sawatzky et

             tolerance differentiate impacts across crab species in the               al., 2020; Punt et al., 2021)

             Arctic; increased productivity and redistribution offshore is

             expected for tanner crab; red king crab and snow crab are

             projected to continue to shift north and decrease in

             productivity. OA is expected to impact demographies, altering

             harvest recommendations and biological reference points for

             some species of some shellfish and flatfish (e.g., red king

             crab, Northern rock sole) in projection simulations.

Climate x    Multiple rights-based fisheries operate in the Arctic,                   (Kasperski and Holland, 2013;
interaction  increasing investment in long-term sustainability but reducing Ojea et al., 2017)

             harvest portfolio diversity and increasing vulnerability to

             climate shocks.

Multiple; sea-ice Physical and biological changes in Antarctic waters are             (Melbourne-Thomas et al., 2016;
                      expected to result in net declines in krill habitat and growth  Pi駉nes and Fedorov, 2016;
                      potential, although one study indicates a potential increase.   Klein et al., 2018; Rogers et al.,
                      Reduction in the Antarctic ice pack is as likely as not to      2020; Veytia et al., 2020)
                      increase total season length in areas near to land-based

            Phytoplankton Projected changes in primary production and temperature are (Pi駉nes and Fedorov, 2016;
            and temperature expected to cause declines in krill growth and availability to Klein et al., 2018)

                                   predators; impacts may be countered by reducing fisheries,
                                   signifying a potential conflict between fisheries and top

 3 CCP6.2.4 Economic Activities
 5 Climate change presents significant risks to economic activities in the polar regions (very high confidence)
 6 and simultaneously enables development possibilities for fisheries (CCP6.2.3.3), agriculture (CCP6.2.3.2),
 7 the sharing and subsistence economy (CCP6.2.3.1) (SMCCP6.2) (high confidence), maritime trade (Box
 8 CCP6.1), natural resource development (CCP6.2.4.1) (medium confidence), tourism (CCP6.2.4.2), and
 9 transportation (including shipping) (CCP6.2.4.3; FAQ CCP6.2). Hundreds of billions of dollars are expected
10 to be invested in the polar regions in the next several decades (Lloyd's, 2012; Barnhart et al., 2016;
11 Pendakur, 2017; Tsukerman et al., 2019) and, as this unfolds, there are opportunities to simultaneously
12 implement adaptation strategies that support climate resilient development pathways in line with self-
13 determination for Indigenous Peoples and local communities and locally derived visions of successful
14 adaptation and development (CCP6.3.2, CCP6.4.3) (Jorgenson, 2007; Ritsema et al., 2015; Ready and
15 Power, 2017; Larsen and Petrov, 2020).

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3 CCP6.2.4.1 Changing access to natural resources with consequences for safety, economic development and

4   climate mitigation


6 Climate change is improving access to natural resources in the Arctic with consequences for human safety

7 (high confidence), economic development (very high confidence) and global mitigation efforts (medium

8 confidence). Reductions in sea-ice combined with improved extraction and transportation technologies have

9 increased accessibility to natural resources across the Arctic (Eliasson et al., 2017; Dawson et al., 2018b;

10 Stephen, 2018); a situation that could support continued global dependence on relatively cheap and abundant

11 fossil fuels resources and contribute to further warming. By 2040 (RCP4.5) it is expected that sea-ice will

12 have receded enough to make gas production technologically feasible in the European off-shore Arctic

13 (Petrick et al., 2017). However, increased sea-ice mobility, iceberg abundance, storm surge, and surface

14 wave action (Ng et al., 2018; Howell and Brady, 2019; Casas-Prat and Wang, 2020) will also increase risks

15 to ships servicing mines in a region that already exhibits disproportionately high accident rates (Council of

16 Canadian Academies, 2016) (CCP6.3.1, Table CCP6.1). Season lengths for ship-based support to mines and

17 extraction sites will increase with sea-ice change, while access via ice roads will decrease with warming

18 (Perrin et al., 2015; Council of Canadian Academies, 2016; Trofimenko et al., 2017; Southcott and Natcher,

19 2018). By 2050, climate change impacts to the Tibbitt to Contwoyto Winter Road servicing mines in the

20 northeastern region of the Northwest Territories, Canada could cost between $55 million to $213 million

21 CAD to maintain for a shorter period of time than at present (Perrin et al., 2015). Changes in submarine

22 permafrost, critical to mining infrastructure, such as pipelines and offshore infrastructure (Bashaw et al.,

23 2016; Paulin and Caines, 2016), are expected to increase production costs and impact safety for workers

24 (Riedel et al., 2017). By mid-century, regardless of emissions scenario, it is expected that risks from

25 permafrost thaw will be disproportionately high for industrial infrastructure along major pipeline systems in

26 Alaska and natural gas extraction areas in the Yamal-Nenets region in northwestern Siberia, Russia (Hjort et

27 al., 2018).


29 CCP6.2.4.2 Changing demand, opportunities and risks for polar tourism


31 Climate change has increased risks to, and demand for, polar tourism experiences related to increased

32 maritime accessibility (high confidence), lengthening of warm weather season lengths (very high confidence)

33 and development of a `last chance tourism market' (medium confidence). Reductions in sea-ice extent have

34 facilitated increased access for polar cruising (Dawson et al., 2018b; Stewart et al., 2020). Demand for Arctic

35 cruises has increased by 20.5% over the past five years and resulted in 27.2 million passengers in 2018

36 (Shijin et al., 2020). In the Antarctic, tourist numbers increased by 27% from 1992-2018 and attracted

37 75,000 visitors in 2019-2020 (IAATO, 2020; Shijin et al., 2020), making it the largest economic sector in the

38 entire region (Stewart et al., 2020). The recent increase in polar tourism is due in part to the development of

39 a niche market called `last chance tourism', which involves explicitly marketing vulnerable or vanishing

40 destinations or features (i.e., glaciers, polar bears, landscapes) and encouraging tourists to see them `before

41 they are gone' (Dawson et al., 2018a; Groulx et al., 2019). However, tourism development opportunities will

42 also contend with ongoing risks related to the COVID19 pandemic, which halted tourism globally in 2020-

43 2021 (Frame and Hemmings, 2020; Lorenzo et al., 2020), as well as those related to increased climatic risks

44 limiting participation and reducing safety and security. By 2100 under RCP8.5, snow cover season length

45 suitable for winter recreational activities is projected to decrease by 21-49% in West Greenland (Schrot et

46 al., 2019). Reduced sea-ice and snow cover creates hazards for and could limit dog sledding, cross country

47 skiing, snowmobiling and floe edge tours, with limited adaptation strategies available for low elevation areas

48 (Stephen, 2018; Palma et al., 2019).


50 CCP6.2.4.3 Risks and opportunities in transportation systems


52 Climate hazards create risks to transportation sectors with consequences for human safety (very high

53 confidence), security (low confidence), and economic development (high confidence). Remote polar regions

54 are highly reliant on transportation systems (air, road, sea) to support and service communities (Arctic) and

55 scientific stations (Antarctic and Arctic). Changes in permafrost, snow, ice, and precipitation patterns have

56 increased the risk of rail infrastructure and of using permanent roads and semi-permanent trails that service

57 Antarctic research stations, connect Arctic communities, and support Indigenous food harvesting activities

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 1 (Calmels et al., 2015; Council of Canadian Academies, 2016; Ford et al., 2019; Stewart et al., 2020).
 2 Warming temperatures have particularly decreased the reliability, safety level, and season length of winter
 3 ice roads (Perrin et al., 2015; Council of Canadian Academies, 2016; G鋎eke et al., 2021) in the northern
 4 Baltic (Finland) (Kiani et al., 2018), James Bay (Canada) (Hori et al., 2018a; Hori et al., 2018b), and Yakutia
 5 (Russia) (Mustonen and Shadrin, 2021). Dog sled travel in northwest Greenland has experienced shorter
 6 season lengths (Nuttall, 2020), Alaskan whale hunters have had difficulty finding suitable ice for safe harvest
 7 activities (Huntington et al., 2016; Nyland et al., 2017), and unpredictability in break-up and freeze-up of
 8 sea-ice has compromised safe travel to and from culturally significant hunting and camping areas in Canada
 9 (Dawson et al., 2020; Simonee et al., 2021), and northeast Siberia (Ksenofontov et al., 2017; Mustonen and
10 Shadrin, 2021). Fog (low confidence) and an increase in precipitation falling as ice pellets or hail (high
11 confidence) (Kochtubajda et al., 2017) is expected to continue to cause operational delays and create safety
12 issues for aviation in the Polar regions (Debortoli et al., 2019).
17 FAQ CCP6.2: Is sea-ice reduction in the polar regions driving an increase in shipping traffic?
19 The polar seas have captured the imagination of global nations for centuries for its natural resource,
20 tourism, scientific, and maritime trade potential. As the polar regions are warming at two to three times the
21 rate of the global average leading to rapid reductions in sea-ice extent and thickness, international attention
22 has been reinvigorated and investments are being made by Arctic and non-Arctic nations alike with a view to
23 utilize newly accessible seaways. Between 2013 and 2019 ship traffic entering the Arctic grew by 25% and
24 the total distance travelled increased by 75%. Similar shipping growth trends are evident in the Antarctic
25 albeit to a lesser extent. Expected growth in Arctic shipping will influence a suite of cascading
26 environmental and cultural risks with implications for Indigenous Peoples.

29                                        CCP6-23                Total pages: 66
        Do Not Cite, Quote or Distribute
FINAL DRAFT                       Cross-Chapter Paper 6  IPCC WGII Sixth Assessment Report

 1 Figure FAQ CCP6.2.1: Projected operational accessibility along Arctic maritime trade routes (Northwest Passage,
 2 Transpolar Route, and Northern Sea Route) under future warming (left) and observed increases in commercial ship
 3 traffic along the routes from 2012-2019
 6 There has been debate among shipping stakeholders, rightsholders, and experts about the extent to which
 7 climate change and sea-ice change is directly influencing increases in shipping activity in the polar regions
 8 relative to other social, technological, political, and economic factors such as commodity prices, tourism
 9 demand, global economic trends, infrastructure support, and service availability. Understanding the
10 connection between climate change and polar shipping activity will allow for more reliable projections of
11 possible future traffic trends and will aid in identifying appropriate adaptation and infrastructure needs
12 required to support future management of the industry. Recent studies have observed increasing statistical
13 correlations between sea-ice change and shipping trends in the polar regions and many have concluded that
14 although economic factors remain the main driver of shipping activities, followed by infrastructure
15 availability, climate change does indeed play a varying but important role in influencing operator intentions.
16 The `opening of polar seaways' due to sea-ice reduction is indeed `enabling' opportunities for polar shipping
17 among all types of vessels due to increasingly accessible areas that were previously covered by multiyear
18 ice, but the extent to which climate change will specifically `drive' an increase in shipping demand remains
19 highly dependent on the vessel type and the reasons for operation. There are certain vessel types, such as
20 those supporting international trade, mining operations or community re-supply, where analysis shows no
21 correlation or weak correlations with sea-ice change suggesting that climate change is enabling these types
22 of ships via increased open water areas and season lengths but that it is not necessarily driving demand.
23 Conversely, there are certain vessel types, such as yachts and cruise ships, where correlations between sea-
24 ice change and traffic increases are stronger, and where there is evidence to suggest that these vessels are
25 indeed driven to visit the polar regions because they perceive waterways as exotic and exciting due to being
26 newly accessible or they want to have a Polar experience before it disappears or is irreversibly changed as is
27 the case with last chance tourists. As sea-ice recedes and polar shipping opportunities grow there will be an
28 increased need to better identify and implement Indigenous self-determined and equitable shipping
29 governance frameworks that facilitate benefits and minimize risks.
36 Box CCP6.1: Climate Change and the Emergence of Future Arctic Maritime Trade Routes
38 Discovering a viable maritime trade route linking the Atlantic and Pacific oceans through the Arctic has
39 captured the collective global imagination for centuries (Bockstoce, 2018). Geographically shorter than
40 southern trade routes via the Panama and Suez Canals, the Arctic presents the possibility for more
41 economical and timely commercial trade, but has historically been limited by thick multi-year ice and other
42 navigational challenges. Amplified warming in the Arctic has caused September sea-ice extent to decline at a
43 rate of -13% per decade (Serreze and Meier, 2019) and reduced sea-ice thickness by 66% (2 m) between
44 1958-1976 and 2011-2018 (Kwok, 2018). Regardless of mitigation efforts, it is expected that before mid-
45 century the Arctic will be seasonally ice free for the first time in 2,600,000 years (defined as < 1,000,000
46 km2) (Knies et al., 2014; SIMIP Community, 2020; Fox-Kemper et al., 2021; Lee et al., 2021) and will make
47 Arctic maritime trade a reality (Egu韑uz et al., 2016; Melia et al., 2016; Pizzolato et al., 2016; Bennett et al.,
48 2020; Wei et al., 2020).
50 There are three identified trade routes in the Arctic: Northern Sea Route (NSR), Northwest Passages (NWP),
51 and the Transpolar Sea Route (TSR). Over the last decade economic trends and reductions in sea-ice have
52 facilitated significant increases in ship traffic in the NSR (Aksenov et al., 2017; Li et al., 2020), including a
53 79% increase in total transit tonnage from 2010 to 2017 (Babin et al., 2020) related mostly to domestic
54 resource development. Relative to an early 21st century baseline, it is expected that the NSR will become
55 18% more accessible by mid-century (Stephenson et al., 2013) and could navigable even for non-ice
56 strengthened vessels for 101-118 days annually by 2050 and 125-192 days by 2100 (Khon et al., 2017). The
57 NWP has experienced a tripling of km travelled by ships since 1990, attributed mostly to resource extraction

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 1 and increases in tourism opportunities (Johnston et al., 2017; Dawson et al., 2018a). The NWP could become
 2 30% more accessible by 2050 compared to current conditions (Stephenson et al., 2013). Before 4癈 global
 3 warming above pre-industrial, re-supply vessels (Polar Class 7) in the western NWP could gain an additional
 4 month of operating time, whereas the eastern NWP could gain just two weeks (Mudryk et al., 2021) due to
 5 the dynamic import of mobile and hazardous ice from the Arctic Ocean (Haas and Howell, 2015; Howell and
 6 Brady, 2019). Comparatively, the TSR has historically only been viable for nuclear icebreakers, submarines,
 7 and occasional military and scientific activity due to thick multiyear ice regimes (Bennett et al., 2020).
 8 However, this most sought-after route offers the greatest reduction in sailing times compared to southern
 9 routes (19-24 days) of all Arctic Sea routes and could be 56% more accessible by mid-century compared to
10 current conditions (Stephenson et al., 2013; Melia et al., 2016).

14 Figure Box CCP6.1.1: Arctic trade routes and projected operations related to sea-ice loss.
17 Growth in Arctic maritime trade will result in increased emission of black carbon (Stephenson et al., 2018;
18 Zhang et al., 2019; Wang et al., 2021), increases in ship-source underwater noise impacts on marine
19 mammals (Halliday et al., 2017), higher rates of accidents and incidents among vessels from increasing
20 mobile sea-ice and newly accessible ice-free waters that lack charting (Haas and Howell, 2015; Howell and
21 Brady, 2019), impacts to cultural sustainability for Indigenous Peoples (Olsen et al., 2019; Dawson et al.,
22 2020) (high confidence), the potential for the introduction and propagation of invasive species (Chan et al.,
23 2019; Rosenhaim et al., 2019), and sovereignty tensions with implications for global geopolitics (Drewniak
24 et al., 2018) (medium confidence). Globalization and the almost universal adherence to economic growth
25 models among nations will continue to fuel maritime trade (Box 14.5). As sea-ice decreases facilitates
26 growth in Arctic maritime trade and transportation specifically, adaptation strategies designed to facilitate
27 mitigation co-benefits and that target the cascading implications and double exposure of climate change and
28 Arctic shipping impacts will be essential in reducing risks (Ng et al., 2018; Pirotta et al., 2019; Bennett et al.,
29 2020; Zeng et al., 2020). Electric and solar powered vessels, new engine and emission reduction
30 technologies, investment in wind, water, ice, and climate forecasting technologies and services (Haavisto et
31 al., 2020; Stewart et al., 2020; Simonee et al., 2021), and efforts by the International Maritime Organization
32 to reduce sulphur and the use of heavy fuel oils (PAME, 2020; van Luijk et al., 2020) could play a key role
33 in limiting emissions and reducing risks related to the environmental and cultural impacts of fuel spills in
34 ice-infested Arctic waters. The development of low impact shipping corridors (Ch閚ier et al., 2017; Dawson
35 et al., 2020) and multilateral agreements such as those implemented by the Arctic Council and Indigenous
36 Peoples' organizations on joint search and rescue (Arctic Council, 2011) and shared spill responsibilities

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 1 (Arctic Council, 2013) represent important co-governance efforts that will be increasingly important in the
 2 future due to projected climate related risks.
 7 CCP6.2.5 Arctic Settlements and Communities
 9 Polar settlements range from large well-serviced cities such as Troms�, Murmansk and Reykjavik, to remote
10 fly-in Indigenous communities, to scientific outposts and research stations. Polar settlements are at
11 significant risk from climate change through shoreline erosion, permafrost thaw, and flooding (high
12 confidence) (CCP6.2.2). Opportunities for community development in small communities are
13 underestimated as they are emergent and unknown (highly likely) (CCP6.2.5).
15 Degradation of ice-rich permafrost can threaten the structural stability and functional capacities of
16 community-based infrastructure (i.e. airports and roads; CCP6.2.5), and can have implications for local
17 economies with coupled impacts for local livelihoods, health and wellbeing (CCP6.2.5, CCP6.2.6) (high
18 confidence). For instance, in Canada, infrastructure damage from permafrost instability caused temporary
19 closures of schools in Yukon, permafrost degradation contributed to runway damage at Iqaluit International
20 Airport in Nunavut, and flooding from heavy rains resulted in thermal erosion of river banks that interrupted
21 water and sewage service in Nunavut (Oldenborger and LeBlanc, 2015; Council of Canadian Academies,
22 2016; Lemmen et al., 2016). In northeast Siberia, the floods of Alazaeya river attributed to thawing
23 permafrost have severely affected Andreyushkino in Yakutia (Mustonen and Shadrin, 2021).
25 By 2050, 69% of fundamental human infrastructure in the Arctic are projected to be at risk under an RCP4.5
26 scenario, including more than 1,200 settlements and 36,000 buildings, leaving 4,000,000 people living in
27 areas with high potential for thaw (Hjort et al., 2018). Widespread permafrost thaw could increase the cost of
28 infrastructure lifecycle replacement by 27% by mid-century under RCP8.5 (Suter et al., 2019). Northern
29 Canada and Western Siberia are at particularly high risk, which are projected to cost additional annual
30 spending of over 1% of annual gross regional product to maintain existing infrastructure (Suter et al., 2019).
31 For instance, under an RCP8.5 scenario, climate change could affect over 19% of structures and
32 infrastructure assets in Russia, which would cost an estimated $84.4 billion USD to mitigate damages
33 (Streletskiy et al., 2019). 54% of residential buildings are projected to be affected by significant permafrost
34 degradation by the mid-century, costing an additional estimated $52.6 billion USD (Streletskiy et al., 2019).
35 SLR and reduced sea-ice protection is projected to compound permafrost thaw damages, including low lying
36 coasts (e.g., along southern Beaufort Sea), low-lying barrier islands (e.g., along Chukchi Sea), and deltas
37 (e.g., Mackenzie, Lena) (Fritz et al., 2017; Lantz et al., 2020). In Alaska, proactive adaptation was
38 substantially cost-saving (reducing costs by $2.9 billion USD for RCP8.5 and $2.3 billion USD for RCP4.5),
39 highlighting the financial benefit of investing in adaptation now (Melvin et al., 2017). Permafrost damage
40 and SLR may result in tipping points, leaving some communities no longer habitable. In Alaska, US, many
41 communities at-risk of flooding and storm surges are already engaged in community-led relocation planning
42 processes (e.g., Shishmaref) (Melvin et al., 2017; Farbotko et al., 2020; Rosales et al., 2021).
44 Climate change has important intangible loss and damage implications in the Arctic, with negative impacts
45 ranging from livelihoods to spirituality to solastalgia (i.e. distress caused by environmental change) (Cunsolo
46 and Ellis, 2018; Middleton et al., 2020b; Sawatzky et al., 2020; Mustonen and Shadrin, 2021). Permafrost
47 thaw, SLR, and reduced sea-ice protection also presents risk to socio-cultural assets, including heritage sites
48 in all Arctic regions (very high confidence) (Friesen, 2015; Hollesen et al., 2016; Radosavljevic et al., 2016;
49 O'Rourke, 2017; Hillerdal et al., 2019; Fenger-Nielsen et al., 2020; Jensen, 2020). A large number of
50 archaeological sites are at risk from climate change in southwest Greenland; Yukon's Beaufort coast,
51 Canada; and Auyuittuq National Park Reserve, Nunavut, Canada (Westley et al., 2011; Hollesen et al., 2018;
52 Irrgang et al., 2019; Fenger-Nielsen et al., 2020). Siberian nomadic reindeer herding and fishing livelihoods
53 are vulnerable to permafrost thaw, which alters northern landscapes and lakes, as well as rain-on-snow
54 events, and rapidly changes landscapes and terrestrial and aquatic habitats (Mustonen and Mustonen, 2016;
55 Brattland and Mustonen, 2018; Mustonen and Huusari, 2020) (CCP6.2.2). The intangible loss and damage to
56 nomadic cultures could cascade to losses of identity and social challenges (CCP6.2.6; Chapter 13).

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4 FAQ CCP6.3: How have Arctic communities adapted to environmental change in the past and will

5   these experiences help them respond now and in the future?


7 For thousands of years Arctic Indigenous Peoples and local communities have survived several major

8 changes to the ecosystems in which they rely; however, the present changes in climate are more challenging

9 than pre- and early historic changes in the Arctic and new unprecedented risks will now face polar

10 communities.


12 The challenges for responding to present change are due to the multiple imposed and simultaneous drivers

13 combined with elimination and/or removal of endemic capacity to respond in culturally and locally

14 appropriate ways. Adapting in the past may therefore inform and produce novel solutions for the present and

15 convey baselines of important contextual information on significance of change. Arctic communities,

16 especially Indigenous Peoples, have been marginalized in terms of their autonomous responses spaces and

17 self-assessment that could be made without external pressures. Therefore, in order to increase the possibility

18 of community-led adaptation, colonialism and the resultant lack of upheld rights, resources and equity need

19 to be solved simultaneously with the present climate change impacts. New research, governance, policy, and

20 collaborations are needed in order to effectively adapt to risks that are projected to emerge in the polar

21 regions as a result of rapid climate change.





26 CCP6.2.6 Human Health and Wellness in the Arctic


28 Climate change continues to have wide-ranging physical human health risks in the Arctic, particularly for

29 Indigenous Peoples (high confidence); however, future projections of physical risks are nascent. Climate

30 change has already challenged food and nutritional security (CCP6.2.5). Climate change also creates safety

31 concerns for those who access the land, ice, and water for food, cultural, and recreational purposes, with

32 changing environmental conditions linked to injury and death (Durkalec et al., 2014; Clark et al., 2016a;

33 Clark et al., 2016b; Driscoll et al., 2016; Brattland and Mustonen, 2018). Foodborne disease risks are

34 expected to increase in the Arctic, with warming temperatures linked to increased risk of microbial

35 contamination of locally harvested foods (Grjibovski et al., 2013; Harper et al., 2015), chemical

36 contamination of locally harvest foods (Hansen et al., 2015; Long et al., 2015; Alava et al., 2017),

37 compromised structural integrity and utility of ice cellars used to store locally harvested meat (Nyland et al.,

38 2017; Markon et al., 2018), and new challenges to traditional food preparation techniques (Shadrin, 2021).

39 Waterborne disease risks have increased, with decreased drinking water quality and quantity, water treatment

40 infrastructure failures, and new waterborne pathogens emerging in the Arctic (Berner et al., 2016; Thivierge

41 et al., 2016; Markon et al., 2018; Yoder, 2018; Masina et al., 2019; Sachal et al., 2019; Harper et al., 2020;

42 Mustonen and Shadrin, 2021). Emerging environmental exposures to pathogens is also a concern. In 2016 a

43 Nenets boy and over 200,000 reindeer died from anthrax linked to warming environments (Ezhova et al.,

44 2021) - a risk which is projected to increase with climate change (Liskova et al., 2021). Thawing permafrost

45 increases smallpox risk in former nomadic campsites and graveyards (Mustonen and Shadrin, 2021; Shadrin,

46 2021). Arctic health systems - which are often already stressed - will be further challenged by climate change

47 (Harper et al., 2015; Clark and Ford, 2017), especially in conjunction with other system shocks (e.g.,

48 COVID-19) (Cross-Chapter Box COVID in Chapter 7) (Zavaleta-Cortijo et al., 2020). While physical health

49 impacts have been observed, research examining future health projections or evaluating the efficacy of

50 health adaptations are rare (Dobson et al., 2015; Harper et al., 2020; Harper et al., 2021).


52 Climate change has negative, widespread and cumulative impacts on mental health in the Arctic, particularly

53 for Indigenous Peoples (very high confidence) (Figure CCP6.3). Climate-sensitive mental health outcomes

54 are complex, overlapping, and interrelated, and have multiple direct and indirect pathways stemming from:

55 acute (e.g., major storms, flooding, wildfires) and chronic (e.g., temperature increases, sea-ice loss,

56 permafrost thaw) environmental conditions, and resulting disruptions to livelihoods, culture, food systems,

57 social connections, health systems, and economies (Cunsolo Willox et al., 2013a; Cunsolo Willox et al.,

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 1 2013b; Cunsolo Willox et al., 2014; Beaumier et al., 2015; Durkalec et al., 2015; Hamilton et al., 2016;
 2 Clayton et al., 2017; Dodd et al., 2018; Jaakkola et al., 2018; Markon et al., 2018; ITK, 2019; Minor et al.,
 3 2019; Middleton et al., 2020a; Middleton et al., 2020b; Feodoroff, 2021).
 5 Negative mental health outcomes from climate change include: emotional reactions (e.g., sadness, fear,
 6 anger, distress, and anxiety); psychosocial outcomes (e.g., depression, post-traumatic stress disorder, and
 7 generalized anxiety); experiences with grief and loss (i.e. ecological grief); increased drug and alcohol usage,
 8 family stress, and domestic violence; increased suicide ideation and suicides; loss of cultural knowledge and
 9 continuity, disruptions to intergenerational knowledge transfer; and deterioration and loss of place-based
10 identities and connections (i.e. solastalgia) (Cunsolo Willox et al., 2013a; Cunsolo Willox et al., 2013b;
11 Cunsolo Willox et al., 2014; Durkalec et al., 2015; Harper et al., 2015; Cunsolo and Ellis, 2018; Hayes et al.,
12 2018; Jaakkola et al., 2018; Markon et al., 2018; Minor et al., 2019; Middleton et al., 2020a; Feodoroff,
13 2021).
15 The negative mental health impacts from climate change are amplified among those most reliant on the
16 environment for subsistence and livelihoods, those who already face chronic physical or mental health
17 issues, and those facing socio-economic inequities and marginalization, particularly for Indigenous Peoples
18 (high confidence). These climate change related mental health impacts are unequally distributed (Cunsolo
19 Willox et al., 2014; Minor et al., 2019), and may vary by gender (Beaumier et al., 2015; Harper et al., 2015;
20 Feodoroff, 2021) and age (Petrasek MacDonald et al., 2013; Ostapchuk et al., 2015; Petrasek MacDonald et
21 al., 2015; Kowalczewski and Klein, 2018).
23 Climate change will increase mental health risks in the Arctic in the future (medium confidence). Future risks
24 include exposures to severe weather events and changing precipitation patterns, sea-ice loss, wildfires, and
25 changing place attachment, as well as disruptions to underlying determinants of mental health and social
26 support networks (Cunsolo Willox et al., 2014; Cunsolo and Ellis, 2018; Markon et al., 2018; Council of
27 Canadian Academies, 2019; ITK, 2019; Middleton et al., 2020a; Middleton et al., 2020b).
29 There is limited evidence assessing adaptation options that effectively reduce climate-related mental health
30 risks, but developing or enhancing access to mental health resources and infrastructure are critical, such as
31 land-based healing programs, enhanced access to culturally-appropriate mental health resources, and
32 climate-specific counselling services to support individual and community psychosocial resilience,
33 particularly among Arctic Indigenous Peoples (Cunsolo and Ellis, 2018; Middleton et al., 2020a).
34 Incorporating a climate-sensitive mental health lens into mitigation and adaptation planning holds potential
35 for increasing mental health and resilience in the Arctic, as well as supporting other social, economic, and
36 cultural co-benefits.

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2 Figure CCP6.3: The pathways through which climate change impacts mental and emotional health in the Arctic.





7 Box CCP6.2: Arctic Indigenous Self-determination in Climate Change Assessment and Decision-

8  making


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 1 Similar to Indigenous Peoples globally (Cross-Chapter Box INDIG in Chapter 18), climate change
 2 vulnerability for Arctic Indigenous Peoples is often rooted in colonialism, which has led to land
 3 dispossession and displacement, carbon-intensive economies, discrimination, racism, marginalization, and
 4 social, cultural, and health inequities (Whyte, 2016; Whyte, 2017; Whyte et al., 2019; Chakraborty and
 5 Sherpa, 2021). Therefore, effective responses to climate change risks for Indigenous Peoples are self-
 6 determined and underpinned by Indigenous knowledge (very high confidence).
 8 Indigenous knowledge systems are diverse among and within Arctic Indigenous Peoples, and reflect deep
 9 and rich knowledge that situates and contextualizes values, traditions, governance, and practical ways of
10 adapting to the ecosystem over millennia (Raymond-Yakoubian et al., 2017; Brattland and Mustonen, 2018).
11 Indigenous knowledge is a valuable source of knowledge; a method to detect change, evaluate risk, and
12 inform adaptation approaches; and a cultural ecological service (Brattland and Mustonen, 2018; Crate et al.,
13 2019; Meredith et al., 2019) that is critical for decision-making (Mustonen and Mustonen, 2016; Huntington
14 et al., 2017). For instance, Kalaallit knowledge in Greenland has been used to detect and attribute long-term
15 (over 50 years) marine change that reaches beyond scientific instrumental data (Mustonen et al., 2018b).
17 This Box was written by Indigenous authors, recognizing that Indigenous knowledge and local knowledge
18 are intellectual property (Cross-Chapter Box INDIG in Chapter 18), alleviating the risk of this knowledge
19 being misinterpreted (David-Chavez and Gavin, 2018; Hughes, 2018; Raymond-Yakoubian and Daniel,
20 2018), and acknowledging that meaningful inclusion of Indigenous Peoples strengthens and supports
21 Indigenous self-determination (ITK, 2019). Self-determination signifies and values the capacity and
22 decisions made by these peoples in their own right and from their own autonomous cultural positioning.
23 Following the format used in SROCC, this Box prioritizes Indigenous voices by presenting climate change
24 assessments premised on Indigenous knowledge and written by Indigenous Peoples.
26 Climate change, nomadic lifestyles, and preservation of traditions
28 Perspectives from the Yukaghir Council of Elders and Russian Association of Indigenous Peoples, Russia
30 Climate change threatens reindeer herding, hunting, fishing, and gathering, which form the basis of Siberian
31 Indigenous societies. Nomadic herding lifestyle is premised on Indigenous knowledge which has
32 accumulated over millennia. IK, including the ability to predict weather, has played a substantial role in the
33 adaptation to the extreme conditions. According to Shadrin (2021) present, rapid changes are changing
34 Indigenous concepts of reality - they are increasingly finding themselves in situations where their experience
35 and knowledge cannot help them. An Elder in Northeast Siberia explained that "nature does not trust us
36 anymore" (Mustonen and Shadrin, 2021).
38 A major problem for nomadic reindeer herding is the degradation of reindeer pastures (Mustonen and
39 Shadrin, 2021). The expansion of willows and shrubs into the tundra has resulted in losses of pastures. In
40 other nomadic communities, these changes have led to the expansion of moose into tundra area and effects of
41 reindeer populations, as well as changes in wild reindeer migration routes leading to the destruction of
42 domestic reindeer pastures (Mustonen and Shadrin, 2021).
44 Due to the steady changes in precipitation in recent years, a deeper than usual snow cover has formed in
45 Northeast Siberia (Mustonen and Shadrin, 2021). This alters the capacity of reindeer to access lichen, their
46 primary food source. Late onset of cold weather has led to difficulties in the herds moving to their winter
47 pastures. In the summer, increased rainfall has led to waterlogging of low-lying pastures. The most important
48 challenge is the instability of the weather (Mustonen and Shadrin, 2021). These include frequent, never-
49 before-seen warming, combined with rains in the late winter and early spring. Sharp temperature drops of
50 over 30 degrees occurring within a few hours leads to formation of an ice crust on the ground which
51 becomes a challenge for reindeer, especially in autumn, and are becoming more frequent. Furthermore, the
52 number of summer storms and rapid cooling accompanied with snowfall during July has increased. Using
53 Indigenous knowledge to predict weather is the basis of effective survival. It has become extremely difficult
54 due to the unprecedented fast changing conditions (Mustonen and Shadrin, 2021) (Shadrin, 2021). All of
55 these events lead to increased risks in the lives of Indigenous Peoples (Mustonen and Shadrin, 2021).

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 1 Climate change impacts Indigenous Peoples' health. Degradation of the quality of surface waters has
 2 increased, resulting from new floods and the thawing of permafrost, which increases risk of gastrointestinal
 3 diseases (CCP6.2.8). The 2007 flood on Alazaya river was of special importance and was locally identified
 4 to have produced the first regional "climate refugees" (Mustonen and Shadrin, 2021). Warming has
 5 expanded the distribution of new disease-carrying insects and ticks into new territories (Mustonen and
 6 Shadrin, 2021). Ancient cemeteries and campsites, as well as the burial sites of reindeer, become dangerous
 7 as permafrost thaws and coastal erosion proceeds.
 9 Traditional food security is under threat. Permafrost-based storage facilities have deteriorated (CCP6.2.6)
10 (Mustonen and Shadrin, 2021). There is an increase in the number of people who are forced to abandon the
11 consumption of raw fish. As a result, the likelihood of losing cultural traditions is growing. These combined
12 climate change impacts result in loss of Indigenous knowledge and nomadic lifestyles, thus, losing important
13 aspects of their identity as distinct Indigenous Peoples (Mustonen and Shadrin, 2021).
15 Climate change impacts on S醡i women
17 Perspectives from S醡i in Finland
19 Feodoroff (2021) stresses that many S醡i women are central to Indigenous-led adaptation. Indigenous
20 women use their bodies as gauges of change. For example, the restoration work in N滗t鋗鰆oki River in
21 Finland (Ogar et al., 2020; Feodoroff, 2021) is based on the knowledge of traditional fishers and reindeer
22 herders. Indigenous knowledge and Western science offer possibilities to reflect on changes that the waters
23 in Indigenous bodies have known of events of the past (Feodoroff, 2021). Changes in temperature, pain and
24 the gradual passing of pain, waves, and intrusions within Indigenous bodies are knowledges that are difficult
25 to communicate according to Feodoroff (2021). Women are sensitive to receiving messages from their home
26 environments. Feodoroff (2021) stresses that Indigenous conservation work is a bodily commitment. This
27 realisation is linked with difficult questions of what or who controls Indigenous bodies. Feodoroff (2021)
28 links present change with lingering impacts of global environmental damage that has not been dealt with or
29 addressed. It may lead to real pain in Indigenous bodies and minds, causing feelings of being nauseated and
30 ultimately causing fade out, wilt, wither and extinguishment of Indigenous Peoples.
32 Adaptation successes underpinned by Inuit knowledge
34 Perspectives from Inuit Circumpolar Council
36 Inuit have survived and thrived in Inuit Nunaat, their homelands, for millennia. In an environment that
37 presents unique challenges, they have cultivated resourceful and innovative approaches tailored to their
38 surroundings. Their values and knowledge guide their relationships with all that is within the Arctic and this
39 has informed their decisions and management practices that continue to be in place today (Inuit Circumpolar
40 Council Alaska, 2020). They are experts in adaptation. Now more than ever, in the time of anthropogenic
41 climate change, living in the fastest warming region on the planet requires this expertise and capacity.
43 The extraordinary developments in the field of Indigenous Knowledge have crystallized the main tenant of
44 interaction with the natural world that is "integral to a cultural complex that also encompasses language,
45 systems of classification, resource use practices, social interactions, ritual and spirituality" (UNESCO,
46 2017). Inuit have used their knowledge of the land and coastal seas to design technology, monitoring
47 systems (Atlas of Community-Based Monitoring in a Changing Arctic, 2021), and new hunting routes that
48 respond to the changes they face (Inuit Circumpolar Council, 2017; Nunavut Climate Change Center, 2018;
49 SIKU, 2020). Such examples of `adaptation success' across Inuit Nunaat have been showcased and
50 celebrated nationally and internationally (Youth Climate Report, 2019) and all are underpinned by Inuit
51 knowledge and pivot on their right to self-determination. This is also embodied, for example, in Canada, the
52 National Inuit Climate Change Strategy outlines the collective Canadian Inuit plan for climate action,
53 centering on Inuit-determined priorities to protect their culture, language, and way of life, and guiding
54 partners in how to work with Inuit on implementing this strategy (ITK, 2019). Their action on adaptation
55 also spans scales from local to international. As far back as 1977, Inuit have been organized and involved at
56 the international level. Inuit were present at the Rio Earth Summit and have participated in diverse but
57 interrelated United Nations conventions to protect their homelands (e.g., UNFCCC, CBD, Stockholm

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1 Convention). This history gives us unique insight and positions us as both leaders and partners with the

2 ability to engage directly with governments, business, and others.


4 However, while Inuit are often recognized as leaders in adaptation, too often the academic literature ends

5 there, citing `successful Inuit-led adaptation to climate change' but not going further to explore towards what

6 END this adaptation is designed. We have demonstrated leadership and set an example for the world in how

7 to respond to change, but successful adaptation is not enough, it is not the end goal.


9 Central to their significant capacity to adapt is that it is done in recognition of the need to move beyond

10 adaptation. Indeed, Inuit-led adaptation action is founded on the intention of contributing to and moving

11 towards reformation and eventual transformation of systems to create a `climate resilient' Arctic. This

12 concept has surfaced in academic climate change literature and discussion and has begun to filter into the

13 climate policy arena, especially within the context of the current COVID-19 pandemic that challenges us all

14 to think about our world differently. With acknowledgement that reform and transformation is needed, the

15 question remains, `What does this look like?'


17 Inuit have an answer. System reform and transformation is grounded in self-determination. It is based in a

18 human rights framework and rooted in Indigenous knowledge and culture. It recognizes and respects

19 interconnectedness and builds this into solutions. It demands collaboration and true partnership towards

20 action. And it comes from thinking big and across scales. Shaping this change calls for willingness and

21 support to rethink the current economic and governance models that have failed us. For example,

22 decentralizing governance and management, while it remains largely unconventional, has been shown to

23 create some of the strongest systems we have. This is, in a large part, due to the way in which

24 decentralization places more value and responsibility on the `self' in self-determination. Decentralized

25 processes in the Arctic have Indigenous knowledge holders playing a key and lead role in determining,

26 defining, deciding how to work towards positive change.


28 Across Inuit Nunaat, examples of direct management and control over lands, territories and resources, have

29 demonstrated that working from what is happening on the ground throughout their homelands, from their

30 priorities and interests, has served to strengthen the health of their environment and their communities. For

31 example, a comparative analysis on factors supporting and impeding Inuit food sovereignty between Alaska

32 and the Inuvialuit Settlement Region found that the difference in outcomes within these regions is dependent

33 on explicit respect for and recognition of the Inuit right of self-determination (Inuit Circumpolar Council

34 Alaska, 2020). Furthermore, a new agreement achieved in Nunavut by the Qikiqtani Inuit Association related

35 to the marine environment touted as an exemplary model for marine management is rooted in Inuit-

36 determined structures and policies, and manifested by Inuit themselves (QIA, 2019).


38 Emphasis on decentralized management and substantial funding to do so at the grassroots level has been

39 recognized by the IPCC previously in the SROCC. Ultimately, going beyond reform to system

40 transformation requires, as Oren Lyons has stated, "value change for survival" (Lyons, 2020). Valuing

41 decentralization, self-determination, Inuit knowledge, interconnectedness � core values held by Inuit � can

42 move us in a climate-resilient direction.





47 CCP6.3        Key Risks and Adaptation


49 CCP6.3.1 Key Risks


51 Key risks arising from changing climate hazards are presented in Table CCP6.6 (details in SMCCP6.4).

52 Changing levels and magnitude of climate hazards translate into different levels of risks for ecosystems,

53 industry, society and infrastructure (Figure CCP6.4) (see Meredith et al., 2019 Figures 3.5, 3.10 (Arctic),

54 Figure 3.6 (Antarctic). In the Arctic, these risks are often also shaped by non-climatic factors (Huntington et

55 al., 2019; Ford et al., 2021), including ongoing colonial legacies, land dispossession, landscape

56 fragmentation, and resulting challenges in the valuing and meaningful use of Indigenous knowledge and

57 local knowledge (Box CCP6.2) (Huntington et al., 2019; Kelman and N鎠s, 2019; Ford et al., 2020).

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1 Available literature enabled assessment of particular polar assets based on projected future risk and including
2 consideration of non-climatic compounding factors under 1�, 2�, 3� and 4癈 global warming above pre-
3 industrial including sea-ice ecosystems, marine mammals, sea birds, fisheries, infrastructure (Arctic only),
4 local mobility (Arctic only), and coastal erosion (Arctic only) (Figure CCP6.5) (details in SMCCP6.4).
7 Table CCP6.5: Key risks and illustrative examples in polar regions identified through the processes described in
8 Chapter 16 and SMCCP6.4.

Key Risk                                          Direct and indirect factors contributing to risk

KR1. Risk to marine ecosystems and                -Warming, marine heatwaves, sea-ice loss, glacial and ice sheet melt,
species (CCP6.2.2; CCP6.2.3)                      ocean acidification, invasive species, harmful algae blooms
                                                  -Narrow thermal niches, altered marine habitat, hampered
                                                  calcification, higher corrosivity for CaCO3 shell/skeleton,
                                                  phenological mismatch, physiological/life history effects, sensitive
                                                  food web relationships, reduced trophic (energy) transfer efficiencies,
                                                  increased light availability, nutrient limitation, and changes to salinity,
                                                  stratification, oxygen levels

KR2. Risk to terrestrial and freshwater           -Warming, hydrological changes, terrestrial heat waves, change in
ecosystems and species (CCP6.2.4)                 rain and snow events, increased wild- and mega-fire events in Arctic,
                                                  permafrost thaw, and erosion
                                                  -Vegetation browning/greening, narrow thermal niches, physiological/
                                                  life history effects, sensitive food web relationships, parasites and

KR3. Risk to commercial and private               -Permafrost freeze-thaw, extreme heat and precipitation, rapid warm-
infrastructure (CCP6.2.6)                         thaw events, storms, increased wave activity, storm surges, flooding,
                                                  landslides and erosion.
                                                  -Roads, airstrips, railways, ports, commercial buildings, private
                                                  homes, ice cellars, traditional snow/ice/water travel routes, other
                                                  -Permafrost freeze-thaw and SLR impacting cultural assets, including
                                                  cultural heritage sites.

KR4. Risk to food and nutritional security        -Warming, ocean acidification, sea-ice loss, permafrost loss, changes
(CCP6.2.5)                                        to precipitation, wildfires, hydrological changes.
                                                  -Access to marine areas increased, to coastal and terrestrial areas
                                                  decreased; effects on subsistence and commercial species.

KR5. Increased polar shipping traffic with        -Substantial reduction in sea-ice extent and thickness.
cascading risks for navigation, safety,           -Marine subsistence species; coastal communities; Inuit hunters; ship
ecosystems, and culture (CCP6.2.4;                operators; tourism operators; mining companies.
CCP6.2.5; Box CCP6.2; FAQ CCP6.1)

KR6. Increased mental health challenges           -Warming temperature; heatwaves; ice changes; changes in snow
and impacts on Indigenous Peoples and             cover; permafrost thaw; coastal erosion; changing landscapes.
culture (CCP6.2.6.4; CCP6.2.7; CCP6.2.8.
Box CCP6.2; FAQ CCP6.3)

          KR7. Risk from polar change for global  -Reduction in Arctic sea-ice, sheets, and glaciers have implications for
          processes and SLR (FAQ CCP6.1)          planetary albedo and ocean stratification and salinity, acceleration of
                                                  global warming, potential effects on global overturning circulation
 9                                                and northern hemisphere weather patterns
10                                                -cultural and resource connections to global sustainable development

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 2 Figure CCP6.4: Rapid assessment for relative risk by sector (y-axis) and climate hazard (x-axis) for polar regions
 3 based on an assessment of asset-specific vulnerability and exposure across climate hazards (see SMCCP6.4 for
 4 methodological details). For each unique combination, the hazard by sector risk was ranked as very high (very high risk
 5 and high confidence), high (significant impacts and risk, high to medium confidence), medium (impacts are detectable
 6 and attributable to climate change, medium confidence), low/ not detected /positive (risk is low or not detectable).
 7 Blank cells are those where the assessment was not applicable or not conducted. Risks identified through the rapid
 8 assessment were further evaluated in the chapter assessments (see corresponding sector text for full assessment of risk
 9 and impacts).



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                                             Sea-ice Ecosystems                       Marine Mammals                          Sea Birds
                                    4 癈                                     4 癈                                    4 癈

    Global mean temperature change  3 癈                                     3 癈                贩�                 3 癈

                                                                        贩                                                                 �

                                    2 癈                                     2 癈                                �   2 癈

                                                        贩              贩�                                                              贩

                                                        贩�             贩                                                               贩�             贩

                                    1 癈                                     1 癈                贩                  1 癈

                                                        贩�                                                                              贩              贩�

                                    0 癈                     Antarctic       0 癈                     Antarctic      0 癈                     Antarctic
                                                Arctic                                   Arctic                                  Arctic

                                             Fisheries                             Infrastructur                     Local
                                    4 癈                                           e                                 Mobility

                                               贩�                           4 癈                        4 癈

                                    3 癈                                贩                       �                    �

    Global mean temperature change             贩                            3 癈                        3 癈

                                    2 癈                                                         �                    �

                                               贩                            2 癈                        2 癈

                                    1 癈                                贩


                                                                        贩� 1 癈                               1 癈


                                    0 癈 Arctic              Antarctic       0 癈 Arctic                 0 癈 Arctic

    Global mean temperature change           Coastal
                                    4 癈


                                    3 癈

                                    2 癈                贩

                                    1 癈                贩

                                    0 癈 Arctic

                                                                                   Level of impact/risk

1                                                                       Undetectable Moderate High Very high

2 Figure CCP6.5: Burning ember of the relative risks to select assets in the Polar regions as a function of global mean

3 surface temperature increase since pre-industrial times including: 1) sea-ice ecosystems, 2) marine mammals, 3) sea

4 birds, 4) fisheries, 5) infrastructure (Arctic only), 6) local mobility (Arctic only), and 7) coastal erosion (Arctic only).

5 The supporting literature and methods are provided in SMCCP6.5



8 CCP6.3.2 Adaptation


10 CCP6.3.2.1 Current adaptation


12 Across polar regions, adaptation responses to climate change impacts have ranged from rapid and

13 incremental (e.g., shifting phenologies, alternative harvest or herding strategies) to large and transformative

14 (e.g., switching livelihoods, social-ecological system transformation) (Figure CCP6.6). Some adaptation

15 measures and opportunities induce novel risks to other sectors or systems resulting in cascading and

16 compounding consequences that are sometimes hard to predict or prepare for (Huntington et al., 2015)

    Do Not Cite, Quote or Distribute                                                                                           CCP6-35                        Total pages: 66
    FINAL DRAFT                          Cross-Chapter Paper 6                     IPCC WGII Sixth Assessment Report

1 (Table CCP6.6). Adaptation planning and implementation is greater in the Arctic than Antarctic regions, in

2 part due to disparate magnitudes of realized climate impacts and change between regions (Figure CCP6.2;

3 Table CCP6.1), but also because of the differing governance systems in place (Meredith et al., 2019). In the

4 Antarctic region, a climate action plan has been developed for terrestrial systems but not for the Southern

5 Ocean (Meredith et al., 2019), although strategies for adapting to climate change have been proposed,

6 including incorporation of precaution in decision-making (Constable et al., 2017). In the Arctic, climate

7 change information is increasingly integrated into research, policy, and decision-making including

8 incorporation of climate change projections, forecasts, and early warnings (AMAP, 2017; AMAP, 2018a;

9 Marshall et al., 2019; Dorn and Zador, 2020; Hollowed et al., 2020; Stram et al., 2021).


11 The majority of adaptations in the Arctic are occurring at sub-regional levels in response to both observed

12 and projected climate change, with evidence of increasing regional level action driven by climate planning

13 processes of subnational governments (AMAP, 2017; Labb� et al., 2017; AMAP, 2018a; Canosa et al.,

14 2020). Implemented adaptation includes alterations to building codes and infrastructure design

15 (Shiklomanov et al., 2017; Flynn et al., 2019; Standards Council of Canada, 2020), surveillance (Ruscio et

16 al., 2015; Ford and Clark, 2019; Meredith et al., 2019), information sharing (Berner et al., 2016), changes to

17 survey and monitoring design (Stevenson and Lauth, 2019), hazard mapping (Flynn et al., 2019), use of new

18 technologies (Tejsner and Veldhuis, 2018; Galappaththi et al., 2019), the development of regional and

19 municipal adaptation plans (Labb� et al., 2017), shifting stocks and changes in fishery operations and

20 location (J鴕gensen et al., 2019; Fedewa et al., 2020; Thompson et al., 2020), alterations to subsistence

21 harvesting activities (Anderson et al., 2018; Ford et al., 2018; Galappaththi et al., 2019), co-production of

22 knowledge (Raymond-Yakoubian and Daniel, 2018), and application of Indigenous knowledge for resource

23 management (Robards et al., 2018) and to monitor storms (Rosales et al., 2021; Simonee et al., 2021). Pan-

24 Arctic and national-level adaptation remains limited (Ford et al., 2014; Canosa et al., 2020), although there

25 have been few efforts to examine the nature of adaptation responses in Arctic regions and large gaps in

26 understanding.


28 Illustrative examples of direct and cascading risks, enabling principles of climate resilience pathways,

29 anticipated future conditions (with certainty levels and compounding risks for key sectors within polar

30 regions are outlined in Table CCP6.6. A list of adaptation options responding directly to the challenges

31 outlined for each sector, including an analysis of adaptation effectiveness and feasibility and cross referenced

32 with key risks assessed in this chapter (Table CCP6.5) is provided in Figure CCP6.6



35 Table CCP6.6: Assessment of risks needing adaptation by sector in the polar regions.

                   Direct and cascading  Enabling principles of Anticipated future             Compounding risks
                   risks                                                                       (non-climatic factors)
    Sector                               climate resilience             conditions / level of

                                         pathways                       certainty

                   Change in extent of sea- Local leadership and Increasing number of Limitations of

                   ice with more storm community-led                    communities needing government budgets,

                   surges, thawing of    initiatives to initiate and relocation (medium other disasters that may

    Coastal        permafrost, sea level drive processes,               confidence), rising costs take priority, policies
    settlements    rise, and coastal erosion responsive agencies,
    (CCP6.2.5)                                                          for mitigating erosion deficiencies for
                                                 established processes
                                                 for assessments and    (high confidence)      addressing mitigation

                                                                                               and relocation

                                         planning, geographic


                   Increased food        Resources to support The intersection of              Underlying health

                   insecurity, waterborne public programs;              social determinants of conditions, advances in

                   disease, emerging     Indigenous self-               health will modify or diagnosis and treatment,

                   pathogens, injury and determination; access to mediate climate change and other health system

    Human health death, and negative     technology; supporting impacts on health (very shocks (e.g., COVID)

    (CCP6.2.6)     mental health outcomes Indigenous knowledge high confidence)


                                         interdisciplinary and

                                         integrated decision-


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              Permafrost thaw, sea- Financial and human Limits to adaptation Level of local, regional,

              ice change, storm surge, resources for: climate exist (high confidence), and national

              coastal erosion,          resilient infrastructure but strategic          infrastructure

Transportation changing precipitation research, development investments in              development,

(aviation, rail, patterns (ice pellets, and implementation; technologically             commitment of national

road, ice roads) hail), and extreme     improved weather,    innovative                 and state level

(CCP6.2.4.3) events create risks to water, ice and climate infrastructure that offers government to

              transportation            forecasting at       mitigation co-benefits sustainable

              infrastructure with       appropriate scales;  will greatly enhance development pathways,

              consequences to           improved             adaptation effectiveness global economic and

              navigation, economics, communications          (very high confidence) political trends,

              safety, and security infrastructure; local                                commodity prices,

                                        search and rescue                               unforeseen system


              Sea-ice reduction         Financial support for Ship traffic will         Geopolitical and

              leading to increased ship-building             continue to grow in sovereignty debates;

              shipping related to       technologies (e.g., low polar regions (high     shipping insurance

Shipping      trade, tourism, fisheries, emission fuels,     confidence) with Arctic premiums; global
(Box CCP6.1;                                                 trade routes becoming economic trends;
FAQ CCP2)     resource development, propulsion               increasing accessible commodity prices;
                                                             (very high confidence) national policies and
              and re-supply with        technologies, hull

              cascading risks from strength); development

              ships such as: increased of robust multi-national albeit with more        politics; level of

              under-water noise,        agreements (in addition challenging navigation infrastructure

              potential introduction of to existing agreements); due to increases in    investment; availability

              invasive species, fuel inclusion of Indigenous mobile ice in the near- of search and rescue

              spill risks, release of Peoples in decision- term compared to late assets, and modern

              black carbon and air making; investment in century when ice is charting

              emissions, impacts to multi-national and       expected to diminish

              cultural resources,       longitudinal research on completely during the

              implications for          shipping impacts; and shipping season (high

              subsistence hunting and enhancing modern       confidence)

              food security, increased digital maritime

              accidents and incidents charting

              Loss and damage to Resources for               Increasing cost to         Strength of regional and

              infrastructure from       assessments, mitigation, maintain infrastructure national economies,

Infrastructure permafrost thaw          and where needed,    and greater demand for other disasters that

(CCP6.2.5) affecting stability of relocation                 technological solutions divert resources

              ground; coastal erosion;                       to prevent damages

              SLR                                            (high confidence)

              Reduced sea-ice           Investment in climate Increase in mining in Commodity prices;

              improves access to non- resilient infrastructure newly accessible marine global economic trends

              renewable resources in and low emission        regions (medium            and shocks; Indigenous

              remote Arctic regions, transportation          confidence), frequent rights and decisions;

Non-renewable while warming             (shipping) and       false starts (i.e., due to changing regulatory

resource      temperature and           investment in solar climatic and non-           environments,

extraction    thawing permafrost        powered ships and low climatic factors) (high geopolitics, global

(Arctic only) affect production levels, impact modular mining confidence), and high demand for resources

(CCP6.2.4.1) quality, and reliability camp infrastructure levels of operational

              and season length of ice                       uncertainty (i.e.,

              roads leading to                               commodity prices,

              increased operational                          economic trends,

              costs                                          climate risks) (very high


              Increased demand for Financial resources for Polar tourism demand Limited search and

              polar tourism activities service and           will continue to           rescue capacity, poor

              including development infrastructure           increase, especially for infrastructure, aging

Tourism       of 'last chance tourism' development;          cruise and yacht           expedition cruise ship
(CCP6.2.4.2)                                                 experiences (high          fleet, uncharted waters,
              market; Increased         Indigenous self-     confidence) and            geological and

              tourism improves          determination and

              economic conditions development of co- enhance risks related to sovereignty debates,

              but leads to increased management              ship groundings,           global economic trends,

              environmental and         approaches for natural accidents, and incidents unforeseen events (i.e.,

              cultural impacts          and cultural attractions; (medium confidence) SARS, COVID-19)

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                                             development of multi                                altering tourism demand

                                             stakeholder/rightsholder                            patterns

                                             tourism task teams

                 Rain-on-snow events Flexibility in movement Increased frequency of Change in market value

                 causing high mortality to respond to changes in extreme events and of meat; overgrazing;

                 of herds, especially in pastures, secure land changing forage quality land use policies

                 the autumn season; use rights; adaptive adding to vulnerabilities affecting access to

Reindeer         shrubification of tundra management; continued of reindeer and herders pasture and migration
(CCP6.2.3.1;     pasture lowering forage economic viability and (high confidence);               routes, property rights;; 6.2.5;
Box CCP6.2)      quality                     cultural tradition; self- adaptation limits are cost of feed

Commercial                                   determination in          being approached
(CCP6.2.3)                                   decision-making;

Marine                                       adequate support for
(CCP6.2.3;                                   communication and
                                             technological services;
ecosystems                                   Indigenous Rights
                                             upheld and protected

                 Loss of sea-ice,            Implementation of         Changes in availability Changes in global

                 warming waters, and adaptive management and location of fishery demand for seafood,

                 MHWs transform              that is closely linked to resources will impact demand and markets,

                 ecosystems in the Arctic monitoring, research, fish operations in the changes in gear,

                 with impacts on             and low cost and          eastern Bering Sea and changes in policies

                 fisheries including         inclusive public          Barents Sea as well as affecting property

                 declines in multiple participation in                 the Convention for the rights. Changes due to

                 regions; changes to decisions, high                   Conservation of           offshore development

                 Antarctic ecosystems resolution forecast and Antarctic Marine Living and transportation

                 affect southern fisheries projection tools,           Resources area.

                 productivity and            climate-informed          Declines in catch

                 distribution                survey and monitoring impact livelihoods,

                                             design                    coastal communities,

                                                                       and pose a risk to

                                                                       regional and global food

                                                                       and nutritional security

                                                                       (very high confidence)

                 Changes in species          Systems of adaptive co- Changes in distribution Changes in cost of fuel,

                 distribution and            management that allow and abundance of              land use affecting

                 abundance (not all          for species switching, resources combined access, food

                 negative); impediments changes in harvesting with more regulations preferences, harvesting

                 to access of harvesting methods and timing, related to species at rights; colonialism,

                 areas especially sea-ice; secure harvesting rights, risk. Adaptation at the international

                 increased interactions communication and local, individual, and agreements to protect

                 with shipping; safety; relationship building, household level under vulnerable species

                 changes in seasonality; co-production of              low mitigation

                 reduced harvesting          knowledge                 scenarios will be costly

                 success and process of                                and possibly

                 food production                                       undermined by the scale

                 (processing, food                                     and pace of change,

                 storage; quality); threats                            including climate

                 to culture and food                                   shocks and extreme

                 security                                              events (medium


                 Warming, sea-ice loss, Reduce effects of              Without institutional Novel and expanding

                 ocean acidification         external and              investment in sustaining activities in ice free

                 resulting in poleward compounding risks and climate resilience in areas (shipping;

                 contraction of polar increase application of ecosystems across                  fishing), energy

                 zones, invasive species ecosystem-based               sectors there is a high development and

                 introduction,               management to meet risk of failure (high mineral extraction,

                 displacement of polar biodiversity and                confidence)               increased tourism,

                 species, and                management goals.                                   global markets and

                 restructuring of food Conservation of genetic                                   demand for polar

                 webs                        diversity and                                       resources, population

                                             biodiversity to preserve                            growth and community

                                             resilience, and

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                                             supplementation and                            relocation to coastal

                                             assisted migration may                         areas

                                             be needed

                    Warming, hydrology Improving biodiversity Without institutional Novel and expanding

                    changes (reduced ice on and redundancy to        investment in sustaining activities in ice free

                    lakes and rivers,        enhance resilience. climate resilience in areas (shipping;

                    flooding, snow) and Efforts to minimize and ecosystems across           fishing), energy

                    permafrost thaw lead to prevent extinctions; sectors there is a high development and

   Terrestrial and  impacts on polar         preservation of         risk of failure (high  mineral extraction,
   Freshwater       terrestrial and          ecosystem processes     confidence). Arctic    increased tourism,
   ecosystems       freshwater systems,      and habitats during     regions have greater   global markets and
   (CCP6.2.2)       food webs, the           critical life stages;   understanding of       demand for polar
                    distribution of polar    coordinated             resilience needs but   resources, population

                    fish, implications for governance; measures coordination is not         growth and community

                    peat systems with        and planning that       widespread. Antarctic relocation to coastal

                    consequent changes on consider dynamic           has established action areas

                    dependent animal         interactions within and plans to identify key

                    assemblages and          among social and        management needs for

                    increasingly favorable ecological systems are conserving terrestrial

                    conditions for parasites more effective          and freshwater biota.

                    and pathogens.

                    Increased risk of

                    wildfires in the Arctic




5 Figure CCP6.6: Assessment of feasibility and effectiveness of adaptation options by key risks in the polar regions
6 (Table CCP6.6)

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 2 The need for self-determination for Indigenous Peoples and local communities in decision-making and
 3 cooperation across Arctic nations to manage a rapidly changing Arctic is increasingly recognized,
 4 particularly in a shipping and wildlife management context where climate impacts will be transboundary and
 5 multi-sectoral (Spence, 2017; Forbis and Hayhoe, 2018; Ford and Clark, 2019; Dawson et al., 2020)
 6 (CCP6.2.6; Box CCP6.2). Effective Indigenous and community-led adaptation efforts have been
 7 implemented across the Arctic to alleviate climate and non-climate stressors and build resilience through
 8 restoration and conservation (Huntington et al., 2017; Brattland and Mustonen, 2018; Hudson and Vodden,
 9 2020; Mustonen and Feodoroff, 2020; Uboni et al., 2020; Huntington et al., 2021). For example, Indigenous
10 knowledge and science has been used by the Skolt S醡i in Finland to attenuate warming, drought, and water
11 quality impacts on salmonids through restoration of spawning and nursery habitats in the Vainosjoki river
12 catchment (Brattland and Mustonen, 2018; Mustonen and Feodoroff, 2020; Ogar et al., 2020). This
13 ecological restoration of damaged habitats for fish represents community-led actions. In Aasiaat,
14 Greenlandic hunters have implemented community-based oceanographic and ecological monitoring to
15 convey Indigenous knowledge observations of rapid change to the government and scientists. A special
16 aspect of land use in the Russian North is the preservation of nomadic lifestyles of the Nenets and Chukchi
17 (Mustonen and Mustonen, 2016), and while these traditional economies have undergone rapid change due to
18 non-climate drivers, their land uses, observational frameworks and cultural matrixes remain of high
19 importance in the context of climate change. Endemic responses (self-agency from within the culture) and
20 Indigenous governance enable adaptation to the rapid and accelerating changes under way (Mustonen et al.,
21 2018a). Therefore, community-based monitoring and inclusion of Indigenous knowledge in dialogue with
22 science has been an effective mechanism to detect and respond to climate change.
24 CCP6.3.2.2 Adaptation gaps
26 In a study of adaptation progress across the Arctic from 2004-2019, 233 cases of adaptation were
27 documented, with the majority of actions primarily behavioural and reactionary in nature and undertaken in
28 the subsistence harvesting sector, with resource management, and infrastructure and transportation other
29 prominent sectors where adaptation responses were documented to be occurring (Canosa et al., 2020). The
30 study found few changes in the profile of adaptation over time, except for an increase in responses being
31 motivated solely by climate impacts, and few cases of transformational change, although caution that a lack
32 of data on adaptation actions makes documenting trends challenging. Human health is generally under-
33 represented in adaptation initiatives, along with adaptations being developed within larger Arctic settlements
34 (Ford et al., 2014; Canosa et al., 2020), and in many sectors decisions continue to be made without explicit
35 inclusion of climate change impacts and risk in planning and design (high confidence) (Cherry et al., 2017;
36 Lauta et al., 2018; Meredith et al., 2019). There is limited evidence of transformational adaptation taking
37 place in the policy arena (e.g., U.S. Executive Order 13990, 2021), but many examples of how impacts and
38 responses to climate change have transformed social-ecological connections, traditions, markets, trade, and
39 livelihoods of Arctic residents and Indigenous Peoples (Ford et al., 2015).
41 CCP6.3.2.3 Maladaptation and limits to adaptation
43 In polar regions, multiple entities operate simultaneously to manage lands and resources, resulting in layered
44 approaches and policies for the same sector or region, only some of which are synergistic and a few of which
45 may counter each other (e.g., Southern Ocean: Solomonsz et al., 2021). Climate change and attendant
46 uncertainty can undermine stakeholder confidence in management, leading to less effective management
47 even when scientific understanding is stable (Mumby et al., 2017). In the Arctic, large landscapes, dispersed
48 population centers, limited resources, and settler colonialism are structural barriers to effective planning,
49 emergency response, and relief and recovery from climate impacts (medium confidence), which limit
50 adaptation and sometimes exacerbate climate and non-climate pressures on social and ecological systems
51 (Ford et al., 2015; Ford et al., 2020; Snook et al., 2020).
53 Adaptation strategies that are beneficial in the short term can result in long-term maladaptive outcomes. For
54 Indigenous Peoples, strategies that fail to address colonialism, inequities, and injustices undermine effective
55 adaptation (Canosa et al., 2020; Schipper, 2020; Ford et al., 2021). Large "responsiveness gaps" between
56 impacts and implementation, approaches that fail to consider dynamic responses within social and ecological
57 systems (which amplify or attenuate climate impacts), and a paucity of a priori planning can contribute to

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 1 maladaptation (high confidence)(Pentz and Klenk, 2017; Turner et al., 2020b). For example, rationalization
 2 (privatization) can stabilize fisheries and incentivize long-term sustainability under stationary conditions, yet
 3 also promote low diversity in harvest (or livelihood) portfolios and when combined with behaviors to offset
 4 climate driven declines in yield (e.g., effort or price) rationalization can create lock-in to declining stocks,
 5 increasing the risk of income variability and collapse (Kasperski and Holland, 2013; Pinkerton and Davis,
 6 2015; Holland et al., 2017; Ojea et al., 2017; Anderies et al., 2019; Fisher et al., 2021). Policies that foster
 7 stewardship yet also allow for diversification in fisheries may further attenuate climate shocks to individual
 8 fisheries (Kasperski and Holland, 2013; Fisher et al., 2021) and stabilize catches (e.g., US Bering Sea
 9 pollock fleet (Watson and Haynie, 2018)). Inclusive and participatory decision-making underpins long-term
10 resilience to climate change (medium confidence)(Flynn et al., 2018; Ford et al., 2020), but a high cost of
11 participation can disproportionately favor entities with strong investment, ample resources, and extreme
12 viewpoints such that decision outcomes are not in the broad interest of polar societies (Lynham et al., 2017).
14 There are significant limits to adaptation in the polar regions related to the rate of warming and cascading
15 changes that are occurring, which is equivalent to double and sometimes triple the global average depending
16 on the region (Bush and Lemmen, 2019; IPCC, 2021). The rapid pace of change, such as sea-ice loss, can
17 outpace ecological processes and induce substantial ecological shifts (CCP6.2)(medium confidence). The
18 speed of climate change in the Arctic limits options for adaptation in communities who rely on a narrow
19 resource base, when adaptation involves loss of culture and livelihoods, and when the costs of adaptation
20 makes it infeasible (medium confidence) (Ford et al., 2015), such as for reindeer herding (Table CCP6.6;
21 Figure CCP6.6; Figure CCP6.7) (Meredith et al., 2019). Adapting infrastructure in response to a rapidly
22 changing cryosphere will be limited by available technologies and the relatively higher costs associated with
23 updating infrastructure over vast polar regions (Schneider von Deimling et al., 2021).

27 Figure CCP6.7: Climate change impacts, risks, and potential for adaptation in Arctic (upper panel) and Antarctic
28 (lower panel) social ecological systems.

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5 FAQ CCP6.4: When will climate change impacts in polar regions surpass our ability to adapt?


7 When environmental variability is within the range of the current adaptive management approaches, the

8 social-ecological system can thrive. However, the rapidly changing polar systems are causing disruptions to

9 societies, economies and ecosystems. The current management systems are yet to develop procedures for

10 managing rapid change being experienced in warming waters, sea-ice declines, permafrost thaw and

11 erosion, and poleward shifts in species. These challenges are expected to become more pronounced within a

12 few decades rather than later this century.


14 Polar regions are naturally dynamic environments. Ecosystems in polar regions, and the people who rely on

15 them, have adapted to natural variability and dynamic nature of polar environments. Fish populations in

16 polar regions are known to exhibit cycles of productivity, and shift their distribution across hundreds of

17 kilometers in response to changes in winter sea-ice cover and concomitant summer ocean conditions.

18 Management of the productive fisheries in polar regions is also designed to allow for these changes, using

19 adaptive and ecosystem based approaches that buffer populations from overexploitation and also stabilize

20 fisheries, livelihoods, and food resources. Indigenous Peoples diversify their subsistence harvest across

21 species and resources, and therefore similarly stabilize food and nutritional security. When environmental

22 variability is within the range of these adaptive measures the social-ecological system can thrive. Thus, there

23 are fundamental components in place in polar regions already to help ecosystems and people adapt to some

24 degree of climate change. However, as climate change impacts like warming waters, sea-ice loss, permafrost

25 thaw and erosion, systematically alter components of the system, shift species increasingly poleward, and

26 disrupt linkages between species and people, the ability to adapt is reduced. There are critical tipping points

27 (e.g., sea ice melt, permafrost thaw) where changes may cascade, self-reinforce and accelerate, outpacing

28 adaptation actions and force natural and human systems irreversibly (on the scale of human existence) into

29 novel regimes. The risk of crossing tipping points is greater and the probability much increased after mid-

30 century under scenarios without global carbon mitigation (SSP5 8.5), where changes are largest and most

31 rapid.





36 CCP6.4        Climate Resilient Development Pathways


38 The polar regions are expected to experience many economic development opportunities as a result of

39 climate change, including increased accessibility for shipping and attractiveness for fisheries and tourism

40 (CCP6.2.3.1, CCP6.2.4). For polar regions, equitable climate resilient development requires diverse

41 perspectives in planning and implementation. In the Arctic, cultural, social and economic dimensions of

42 Indigenous Peoples and local communities are critical (Ritsema et al., 2015; Huntington et al., 2021). For

43 both poles, there are global cultural connections to polar systems (Roberts et al., 2021), along with important

44 global and local needs for sustained ecosystems and their services, in the face of diminishing polar zonal

45 conditions (Cavanagh et al., 2021; Murphy et al., 2021; Solomonsz et al., 2021).


47 Sustainable pathways integrating across sectors, and taking account of local and global connections, can be

48 readily achieved in polar regions to balance trade-offs between economic, ecological, and socio-cultural

49 imperatives, yet challenges remain (Murphy et al., 2021). Notably, terrestrial areas of greatest interest for

50 infrastructure development, agriculture, and visitation potential are often also the same areas that have been

51 identified as culturally and ecologically significant (PEW, 2016; Eliasson et al., 2017; Grant et al., 2021)

52 (high confidence). Development of low impact shipping corridors in Arctic Canada is an example of an

53 effective mechanism where climate resilient infrastructure can be prioritized and where regulation (voluntary

54 and enforced) focused on cascading climatic risks can be implemented (Ch閚ier et al., 2017; Dawson et al.,

55 2020).


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 1 CCP6.4.1 Challenges to Climate Resilient Development Pathways
 3 Decision-making in polar regions is complicated by globalization processes and the complexity of
 4 governance arrangements from local to global instruments and differing stakeholder perspectives and needs
 5 (Hughes et al., 2018; Stephen, 2018; Huntington et al., 2021; Murphy et al., 2021; Solomonsz et al., 2021).
 6 Substantial interest in and management of polar resources from non-polar states can lead to decision-making
 7 that lacks explicit consideration of local impacts and responses, thus reducing the effectiveness of
 8 adaptation, and in some cases causing maladaptation. Participatory decision-making is increasingly used in
 9 some sectors, but high costs of participation, a focus on consensus, and systematic erosion of resources can
10 undermine outcomes (Mumby et al., 2017; Parlee and Wiber, 2018; Mendenhall et al., 2020). In the Arctic,
11 the societal burden of climate change impacts and risks will manifest at the local level and thus the
12 importance of local scale leadership and involvement in decision-making is essential for effective adaptation
13 (AMAP, 2017).
15 Many losses and damages within Indigenous contexts are not able to be monetized but can be profound, such
16 as loss of Indigenous languages (CAFF, 2013), loss of Indigenous knowledge associated with nomadic
17 lifestyles and cultures (Box CCP6.2), and loss of geographical knowledge associated with an intimate
18 knowledge of landscapes across seasons (Brattland and Mustonen, 2018), changing landscapes resulting in
19 solastalgia and ecological grief (Cunsolo and Ellis, 2018), and some Indigenous practices and cultural assets,
20 such as burial grounds, nomadic camp sites, graveyards, seasonal dwellings, and routes and pathways
21 causing disruptions to mind and memory (Mustonen and Mustonen, 2016). Recognizing these intangible
22 losses and damages is critical for understanding how to achieve climate resilience in the Arctic (Tschakert et
23 al., 2019; Sawatzky et al., 2020).
25 For the Antarctic, the governance for managing climate impacts is emerging, particularly for terrestrial and
26 nearshore habitats (high confidence) (Hughes et al., 2018; Chown and Brooks, 2019). However, it is poorly
27 developed for marine ecosystems, despite its importance for decision-making (Trebilco et al., 2020;
28 Goldsworthy and Brennan, 2021). A diversity of stakeholders are involved in developing evidence-based
29 management for the region, which presents challenges for adaptation planning (Solomonsz et al., 2021),
30 particularly in identifying sustainable practices in a changing environment (Constable et al., 2017; Brooks et
31 al., 2018). Spatial management for enhancing the resilience of endemic polar biodiversity is increasingly
32 proposed as the best option for managing risks of climate change (Chown and Brooks, 2019).
34 CCP6.4.2 Inclusive, Integrated Co-management
36 Inclusive, low-cost participatory decision-making can deliver equitable responses to climate change (high
37 confidence). Land use, maritime activities, and subsistence fishery and other extracted resources in the polar
38 regions are co-managed through multilateral and national government bodies. The capacity of governance
39 systems in some Arctic regions to respond to climate change has strengthened recently (high confidence).
40 Synthetic themes in adaptation for the Arctic have emerged from and since SROCC and include flexibility
41 through diversity in livelihoods, and subsistence and harvest portfolios; co-management of resources;
42 adaptive and ecosystem-based approaches; adoption of advanced technology, forecasts, and longer term
43 projections to improve safety and resources management; and imperative need for low-cost, inclusive and
44 participatory decision-making (Kasperski and Holland, 2013; Brattland and Mustonen, 2018; Parlee and
45 Wiber, 2018; Galappaththi et al., 2019; Holsman et al., 2020; Huntington et al., 2021; Melbourne-Thomas et
46 al., 2021; Mustonen and Van Dam, 2021). This was demonstrated in community-level adaptation by
47 Pangnirtung Inuit to climate change impacts on fisheries (Galappaththi et al., 2019). Inclusive approaches to
48 co-management, especially those that enable diverse perspectives, embrace conflict, and address equity and
49 justice across power holders, can help alleviate the risk and promote solutions (Raymond-Yakoubian et al.,
50 2017; Brattland and Mustonen, 2018; Parlee and Wiber, 2018; Raymond-Yakoubian and Daniel, 2018;
51 Snook et al., 2020). Integration across levels of management and diverse regional perspectives can reduce
52 climate risks and support equitable adaptation measures (Allison and Bassett, 2015; Raymond-Yakoubian et
53 al., 2017; Raymond-Yakoubian and Daniel, 2018; Holsman et al., 2020).
55 Increased flexibility in management measures, greater investment in ecosystem monitoring, and more
56 inclusive participatory methods and communication may help foster high levels of local investment and
57 resilience and promote adaptive pathways (Cinner et al., 2016; Weymouth and Hartz-Karp, 2019), although

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1 explicit measures may be needed to reduce costs and increase representation, enhance transparency, embrace

2 dissent, and clarify accountability are needed as these are not inherent outcomes (Lynham et al., 2017; Parlee

3 and Wiber, 2018). Ecosystem-based management (EBM), which includes provisions aimed at sustaining

4 critical connections within and among social and ecological systems, enhances resilience and attenuates

5 climate impacts on ecosystems and provisioning services, e.g., EBM enhances climate resilience for

6 Antarctic krill and Northeast Arctic cod fisheries (Troell et al., 2017; Meyer et al., 2020) and forestalls

7 fishery collapse in the Bering Sea in the near-term (Holsman et al., 2020). Increasing likelihood of

8 transboundary resources, interactions, and novel commerce may strain existing regulatory and international

9 agreements suggests that a priori governance agreements that designed to manage climate risks and aimed at

10 attenuating potential conflicts over resources and regions may be important for resolving these issues (Parlee

11 and Wiber, 2018; Mendenhall et al., 2020).


13 CCP6.4.3 Enabling Climate Resilience in the Arctic: Self-determination and Indigenous Peoples'

14  Rights


16 Climate change disproportionately impacts Indigenous Peoples (Box CCP6.2), which directly affects their

17 livelihoods, health, and Sustainable Development Goal targets. For residents in the Arctic, a sustainable

18 development pathway has been found to be highly effective if a self-determined development model is

19 employed (very high confidence). Known determinants of Indigenous self-determined development in

20 regions in the Arctic, include: 1) Indigenous self-determined decision-making (and inherent sovereignty); 2)

21 effective and culturally legitimate institutions of government; 3) strategic vision and strategic thinking; and

22 4) public-spirited, nation-building leadership (Cornell and Kalt, 1992; Cornell and Kalt, 1998; Cornell and

23 Kalt, 2007; Ritsema et al., 2015). For Indigenous Peoples, advances in recognition of self-governance, land

24 and resource sovereignty, and resource co-management, particularly in the North American Arctic but also

25 elsewhere, provide a strong basis for responding to climate impacts (Ford et al., 2015; Robards et al., 2018).

26 These developments expand the solution space (Haasnoot et al., 2020) for responding to climate impacts,

27 although historical and on-going forms of colonialism in research and government institutions continues to

28 undermine Indigenous self-determination and reinforce climate change vulnerability (Marino and Lazrus,

29 2015; Whyte et al., 2019; Ford et al., 2020; Snook et al., 2020). Readiness for adaptation across Arctic

30 nations continues to be challenged by a number of factors including the existence of pressing socio-

31 economic challenges, institutional and governmental barriers, lack of meaningful inclusion of Indigenous

32 knowledge in government planning and response, and lack of financial resources (Ford et al., 2015; Loring et

33 al., 2016; AMAP, 2017; Ford et al., 2017; Birchall and Bonnett, 2019) (AMAP, 2018a). In Alaska, for

34 example, the need to relocate high risk villages has been recognized by researchers, decision-makers, and

35 communities themselves for some time, and while progress is being made in some locations (Ristroph,

36 2017), institutional barriers have generally resulted in negligible progress (Bronen and Chapin, 2013; Marino

37 and Lazrus, 2015; Albert et al., 2018; Rosales et al., 2021).



40 CCP6.5        Summary and Conclusion


42 Rapid changes occurring in polar systems are clear and unequivocal, indicating that swift and effective

43 responses are urgently needed to avoid substantial future impacts and reduce risks to polar social and

44 ecological systems. Some underlying principles emerge from this assessment that appear fundamental to

45 achieving climate resilient development in polar systems (Figure CCP6.8) because they could facilitate

46 rapid, equitable and just responses to achieve climate resilience. These principles include having locally

47 relevant and accessible tools and services (e.g., regional forecasts and projections) to support climate-

48 informed decision-making, along with adequate and appropriate resourcing (including finance and integrated

49 planning) for climate adaptation and for responding to emergencies. Effective decision-making processes

50 integrate across sectors, all levels of governance, including through multinational instruments, and, most

51 importantly, apply low cost and inclusive participatory processes to address gender, equitable and socially

52 just outcomes. In the Arctic, there is evidence that overcoming colonialism through meaningful and explicit

53 inclusion of Indigenous knowledge in research and resource management, as well as co-management and

54 self-determination in decision-making, are effective measures to support equitable climate resilience across

55 multiple sectors. Lastly, climate resilience is strongly dependent on both mitigation of climate change as well

56 as effective adaptation to meet the challenges of unprecedented change in polar regions.


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3 Figure CCP6.8: Six principles that support climate resilient pathways in the polar regions.

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