Summary for Policymakers

      Table of Contents

      A: Introduction      7
SPM       Box SPM.1 | AR6 Common Climate Dimensions, Global Warming Levels and Reference Periods                                                                                                                                       9

      B: Observed and Projected Impacts and Risks                                                     10
          Observed Impacts from Climate Change                                          11
          Vulnerability and Exposure of Ecosystems and People                                                         14
          Risks in the near term (2021–2040)                                  15
          Mid to Long-term Risks (2041–2100)                                      16
          Complex, Compound and Cascading Risks                                              20
          Impacts of Temporary Overshoot                               21

      C: Adaptation Measures and Enabling Conditions                                                            22
          Current Adaptation and its Benefits                                 22
          Future Adaptation Options and their Feasibility                                               23
          Limits to Adaptation              28
          Avoiding Maladaptation                     29
          Enabling Conditions               29

      D: Climate Resilient Development                                    30
          Conditions for Climate Resilient Development                                               31
          Enabling Climate Resilient Development                                         31
          Climate Resilient Development for Natural and Human Systems                                                                        33
          Achieving Climate Resilient Development                                          35

                                                                                                                                                                         Summary for Policymakers

A: Introduction

This Summary for Policymakers (SPM) presents key findings of the Working Group II (WGII) contribution to the Sixth Assessment Report (AR6) of
the IPCC1. The report builds on the WGII contribution to the Fifth Assessment Report (AR5) of the IPCC, three Special Reports2, and the Working
Group I (WGI) contribution to the AR6 cycle.

This report recognizes the interdependence of climate, ecosystems and biodiversity3, and human societies (Figure SPM.1) and integrates                                                                                 SPM
knowledge more strongly across the natural, ecological, social and economic sciences than earlier IPCC assessments. The assessment of climate
change impacts and risks as well as adaptation is set against concurrently unfolding non-climatic global trends e.g., biodiversity loss, overall
unsustainable consumption of natural resources, land and ecosystem degradation, rapid urbanisation, human demographic shifts, social and
economic inequalities and a pandemic.

The scientific evidence for each key finding is found in the 18 chapters of the underlying report and in the 7 cross-chapter papers as well as the
integrated synthesis presented in the Technical Summary (hereafter TS) and referred to in curly brackets {}. Based on scientific understanding, key
findings can be formulated as statements of fact or associated with an assessed level of confidence using the IPCC calibrated language4. The WGII
Global to Regional Atlas (Annex I) facilitates exploration of key synthesis findings across the WGII regions.

The concept of risk is central to all three AR6 Working Groups. A risk framing and the concepts of adaptation, vulnerability, exposure, resilience,
equity and justice, and transformation provide alternative, overlapping, complementary, and widely used entry points to the literature assessed
in this WGII report.

Across all three AR6 working groups, risk5 provides a framework for understanding the increasingly severe, interconnected and often irreversible
impacts of climate change on ecosystems, biodiversity, and human systems; differing impacts across regions, sectors and communities; and
how to best reduce adverse consequences for current and future generations. In the context of climate change, risk can arise from the dynamic
interactions among climate-related hazards6 (see Working Group I), the exposure7 and vulnerability8 of affected human and ecological systems.
The risk that can be introduced by human responses to climate change is a new aspect considered in the risk concept. This report identifies 127
key risks9. {1.3, 16.5}

The vulnerability of exposed human and natural systems is a component of risk, but also, independently, an important focus in the literature.
Approaches to analysing and assessing vulnerability have evolved since previous IPCC assessments. Vulnerability is widely understood to differ
within communities and across societies, regions and countries, also changing through time.

Adaptation10 plays a key role in reducing exposure and vulnerability to climate change. Adaptation in ecological systems includes autonomous
adjustments through ecological and evolutionary processes. In human systems, adaptation can be anticipatory or reactive, as well as incremental

1    Decision IPCC/XLVI-3, The assessment covers scientific literature accepted for publication by 1 September 2021.
2    The three Special Reports are: ‘Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission
     pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty (SR1.5)’; ‘Climate Change and Land. An IPCC
     Special Report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems (SRCCL)’; ‘IPCC Special Report
     on the Ocean and Cryosphere in a Changing Climate (SROCC)’.
3    Biodiversity: Biodiversity or biological diversity means the variability among living organisms from all sources including, among other things, terrestrial, marine and other aquatic ecosystems, and the
     ecological complexes of which they are part; this includes diversity within species, between species, and of ecosystems.
4    Each finding is grounded in an evaluation of underlying evidence and agreement. 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. 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%,
     as likely as not 33–66%, unlikely 0–33%, very unlikely 0–10%, exceptionally unlikely 0–1%. Assessed likelihood is typeset in italics, e.g., very likely. This is consistent with AR5 and the other AR6 Reports.
5    Risk is defined as the potential for adverse consequences for human or ecological systems, recognising the diversity of values and objectives associated with such systems.
6    Hazard is defined as the potential occurrence of a natural or human-induced physical event or trend that may cause loss of life, injury, or other health impacts, as well as damage and loss to property,
     infrastructure, livelihoods, service provision, ecosystems and environmental resources. Physical climate conditions that may be associated with hazards are assessed in Working Group I as climatic
7    Exposure is defined as the presence of people; livelihoods; species or ecosystems; environmental functions, services and resources; infrastructure; or economic, social or cultural assets in places and
     settings that could be adversely affected.
8    Vulnerability in this report is defined as the propensity or predisposition to be adversely affected and encompasses a variety of concepts and elements, including sensitivity or susceptibility to harm and
     lack of capacity to cope and adapt.
9    Key risks have potentially severe adverse consequences for humans and social-ecological systems resulting from the interaction of climate related hazards with vulnerabilities of societies and systems
10   Adaptation is defined, in human systems, as the process of adjustment to actual or expected climate and its effects in order to moderate harm or take advantage of beneficial opportunities. In natural
     systems, adaptation is the process of adjustment to actual climate and its effects; human intervention may facilitate this.


    From climate risk to climate resilient development: climate, ecosystems (including biodiversity) and human society as coupled systems
    (a) Main interactions and trends                                                                                                          (b) Options to reduce climate risks and establish resilience

                                          Climate Change                                                                                                                       Future Climate Change
                                                 causes                                                                                                                          Limiting Global Warming
                                            Impacts and Risks
                                                                                                                                                                                                                                                       Summary for Policymakers

                                                                                                                From urgent to
                                                                                                                 timely action
                                                                                                                                                                                Human health & well-being
                                                                                                                                                                                     equity, justice
                                                                                                               Governance                             Human Systemss                 Ecosystem health                Ecosystems
            Human Society                                                Ecosystems                               Finance                               Transitions                  Planetary health                Transitions
           Limits to adaptationn                                    including biodiversity
                                                                    includ                                Knowledge and capacity                       Societal | Energy                                           Land | Freshwater
           Losses and damagess                                          Lim to adaptation
                                                                        Limits                                                                      Industry | Urban, Rural
                                                                                                                                                                         ral                                        Coastal | Ocean
                                                                                                           Catalysing conditions
                                                                        Losses and damages                                                             & Infrastructure                                             Ecosystems and
                                                                                                               Technologies                                                                                        their biodiversity

    The risk propeller shows that risk emerges from the overlap of:
        Climate hazard(s)                          Vulnerability                        Exposure

                                             ...of human systems, ecosystems and their biodiversity

    Figure SPM.1 | This report has a strong focus on the interactions among the coupled systems climate, ecosystems (including their biodiversity) and human society. These interactions are the basis of emerging risks
    from climate change, ecosystem degradation and biodiversity loss and, at the same time, offer opportunities for the future.
    (a) Human society causes climate change. Climate change, through hazards, exposure and vulnerability generates impacts and risks that can surpass limits to adaptation and result in losses and damages. Human society can adapt to,
    maladapt and mitigate climate change, ecosystems can adapt and mitigate within limits. Ecosystems and their biodiversity provision livelihoods and ecosystem services. Human society impacts ecosystems and can restore and conserve them.
    (b) Meeting the objectives of climate resilient development thereby supporting human, ecosystem and planetary health, as well as human well-being, requires society and ecosystems to move over (transition) to a more resilient state.
    The recognition of climate risks can strengthen adaptation and mitigation actions and transitions that reduce risks. Taking action is enabled by governance, finance, knowledge and capacity building, technology and catalysing conditions.
    Transformation entails system transitions strengthening the resilience of ecosystems and society (Section D). In a) arrow colours represent principle human society interactions (blue), ecosystem (including biodiversity) interactions (green)
    and the impacts of climate change and human activities, including losses and damages, under continued climate change (red). In b) arrow colours represent human system interactions (blue), ecosystem (including biodiversity) interactions
    (green) and reduced impacts from climate change and human activities (grey). {1.2, Figure 1.2, Figure TS. 2}
                                                                                                                                                                         Summary for Policymakers

and/ or transformational. The latter changes the fundamental attributes of a social-ecological system in anticipation of climate change and its
impacts. Adaptation is subject to hard and soft limits11.

Resilience12 in the literature has a wide range of meanings. Adaptation is often organized around resilience as bouncing back and returning to
a previous state after a disturbance. More broadly the term describes not just the ability to maintain essential function, identity and structure,
but also the capacity for transformation.
This report recognises the value of diverse forms of knowledge such as scientific, as well as Indigenous knowledge and local knowledge in
understanding and evaluating climate adaptation processes and actions to reduce risks from human-induced climate change. AR6 highlights
adaptation solutions which are effective, feasible13, and conform to principles of justice14. The term climate justice, while used in different ways in
different contexts by different communities, generally includes three principles: distributive justice which refers to the allocation of burdens and
benefits among individuals, nations and generations; procedural justice which refers to who decides and participates in decision-making; and
recognition which entails basic respect and robust engagement with and fair consideration of diverse cultures and perspectives.

Effectiveness refers to the extent to which an action reduces vulnerability and climate-related risk, increases resilience, and avoids maladaptation15.

This report has a particular focus on transformation16 and system transitions in energy; land, ocean, coastal and freshwater ecosystems; urban,
rural and infrastructure; and industry and society. These transitions make possible the adaptation required for high levels of human health and
well-being, economic and social resilience, ecosystem health17, and planetary health18 (Figure SPM.1). These system transitions are also important
for achieving the low global warming levels (Working Group III) that would avoid many limits to adaptation11. The report also assesses economic
and non-economic losses and damages19. This report labels the process of implementing mitigation and adaptation together in support of
sustainable development for all as climate resilient development20.

     Box SPM.1 | AR6 Common Climate Dimensions, Global Warming Levels and Reference Periods

     Assessments of climate risks consider possible future climate change, societal development and responses. This report assesses literature
     including that based on climate model simulations that are part of the fifth and sixth Coupled Model Intercomparison Project Phase
     (CMIP5, CMIP6) of the World Climate Research Programme. Future projections are driven by emissions and/or concentrations from
     illustrative Representative Concentration Pathways (RCPs)21 and Shared Socioeconomic Pathways (SSPs)22 scenarios, respectively23.
     Climate impacts literature is based primarily on climate projections assessed in AR5 or earlier, or assumed global warming levels, though
     some recent impacts literature uses newer projections based on the CMIP6 exercise. Given differences in the impacts literature regarding

11	Adaptation limits: The point at which an actor’s objectives (or system needs) cannot be secured from intolerable risks through adaptive actions.
    Hard adaptation limit—No adaptive actions are possible to avoid intolerable risks.
    Soft adaptation limit—Options may exist but are currently not available to avoid intolerable risks through adaptive action.
12   Resilience in this report is defined as the capacity of social, economic and ecosystems to cope with a hazardous event or trend or disturbance, responding or reorganising in ways that maintain their
     essential function, identity and structure as well as biodiversity in case of ecosystems while also maintaining the capacity for adaptation, learning and transformation. Resilience is a positive attribute
     when it maintains such a capacity for adaptation, learning, and/or transformation.
13   Feasibility refers to the potential for an adaptation option to be implemented.
14   Justice is concerned with setting out the moral or legal principles of fairness and equity in the way people are treated, often based on the ethics and values of society. Social justice comprises just or
     fair relations within society that seek to address the distribution of wealth, access to resources, opportunity and support according to principles of justice and fairness. Climate justice comprises justice
     that links development and human rights to achieve a rights-based approach to addressing climate change.
15   Maladaptation refers to actions that may lead to increased risk of adverse climate-related outcomes, including via increased greenhouse gas emissions, increased or shifted vulnerability to climate
     change, more inequitable outcomes, or diminished welfare, now or in the future. Most often, maladaptation is an unintended consequence.
16   Transformation refers to a change in the fundamental attributes of natural and human systems.
17   Ecosystem health: a metaphor used to describe the condition of an ecosystem, by analogy with human health. Note that there is no universally accepted benchmark for a healthy ecosystem. Rather,
     the apparent health status of an ecosystem is judged on the ecosystem’s resilience to change, with details depending upon which metrics (such as species richness and abundance) are employed in
     judging it and which societal aspirations are driving the assessment.
18   Planetary health: a concept based on the understanding that human health and human civilisation depend on ecosystem health and the wise stewardship of ecosystems.
19   In this report, the term ‘losses and damages’ refers to adverse observed impacts and/or projected risks and can be economic and/or non-economic.
20   In the WGII report, climate resilient development refers to the process of implementing greenhouse gas mitigation and adaptation measures to support sustainable development for all.
21   RCP-based scenarios are referred to as RCPy, where ‘y’ refers to the level of radiative forcing (in watts per square meter, or W m-2) resulting from the scenario in the year 2100.
22   SSP-based scenarios are referred to as SSPx-y, where ‘SSPx’ refers to the Shared Socioeconomic Pathway describing the socioeconomic trends underlying the scenarios, and ‘y’ refers to the level of
     radiative forcing (in watts per square meter, or W m-2) resulting from the scenario in the year 2100.
23   IPCC is neutral with regard to the assumptions underlying the SSPs, which do not cover all possible scenarios. Alternative scenarios may be considered or developed.

      Summary for Policymakers

           Box SPM.1 (continued)

           socioeconomic details and assumptions, WGII chapters contextualize impacts with respect to exposure, vulnerability and adaptation as
           appropriate for their literature, this includes assessments regarding sustainable development and climate resilient development. There are
           many emissions and socioeconomic pathways that are consistent with a given global warming outcome. These represent a broad range
SPM        of possibilities as available in the literature assessed that affect future climate change exposure and vulnerability. Where available, WGII
           also assesses literature that is based on an integrative SSP-RCP framework where climate projections obtained under the RCP scenarios
           are analysed against the backdrop of various illustrative SSPs22. The WGII assessment combines multiple lines of evidence including
           impacts modelling driven by climate projections, observations, and process understanding. {1.2, 16.5, 18.2, CCB CLIMATE, WGI AR6
           SPM.C, WGI AR6 Box SPM.1, WGI AR6 1.6, WGI AR6 12, AR5 WGI}

           A common set of reference years and time periods are adopted for assessing climate change and its impacts and risks: the reference
           period 1850–1900 approximates pre-industrial global surface temperature, and three future reference periods cover the near-term
           (2021–2040), mid-term (2041–2060) and long-term (2081–2100). {CCB CLIMATE}

           Common levels of global warming relative to 1850–1900 are used to contextualize and facilitate analysis, synthesis and communication
           of assessed past, present and future climate change impacts and risks considering multiple lines of evidence. Robust geographical
           patterns of many variables can be identified at a given level of global warming, common to all scenarios considered and independent of
           timing when the global warming level is reached. {16.5, CCB CLIMATE, WGI AR6 Box SPM.1, WGI AR6 4.2, WGI AR6 CCB11.1}

           WGI assessed the increase in global surface temperature is 1.09 [0.95 to 1.20]24 °C in 2011–2020 above 1850–1900. The estimated
           increase in global surface temperature since AR5 is principally due to further warming since 2003–2012 (+0.19 [0.16 to 0.22] °C).25
           Considering all five illustrative scenarios assessed by WGI, there is at least a greater than 50% likelihood that global warming will reach
           or exceed 1.5°C in the near‐term, even for the very low greenhouse gas emissions scenario26. { WGI AR6 SPM A1.2, WGI AR6 SPM B1.3,
           WGI AR6 Table SPM.1, WGI AR6 CCB 2.3}

      B: Observed and Projected Impacts and Risks

      Since AR5, the knowledge base on observed and projected impacts and risks generated by climate hazards, exposure and vulnerability has
      increased with impacts attributed to climate change and key risks identified across the report. Impacts and risks are expressed in terms of their
      damages, harms, economic, and non-economic losses. Risks from observed vulnerabilities and responses to climate change are highlighted.
      Risks are projected for the near-term (2021–2040), the mid (2041–2060) and long term (2081–2100), at different global warming levels and
      for pathways that overshoot 1.5°C global warming level for multiple decades27. Complex risks result from multiple climate hazards occurring
      concurrently, and from multiple risks interacting, compounding overall risk and resulting in risks transmitting through interconnected systems
      and across regions.

      24   In the WGI report, square brackets [x to y] are used to provide the assessed very likely range, or 90% interval.
      25   Since AR5, methodological advances and new datasets have provided a more complete spatial representation of changes in surface temperature, including in the Arctic. These and other improvements
           have also increased the estimate of global surface temperature change by approximately 0.1°C, but this increase does not represent additional physical warming since AR5.
      26   Global warming of 1.5°C relative to 1850–1900 would be exceeded during the 21st century under the intermediate, high and very high greenhouse gas emissions scenarios considered in this report
           (SSP2-4.5, SSP3-7.0 and SSP5-8.5, respectively). Under the five illustrative scenarios, in the near term (2021–2040), the 1.5°C global warming level is very likely to be exceeded under the very high
           greenhouse gas emissions scenario (SSP5-8.5), likely to be exceeded under the intermediate and high greenhouse gas emissions scenarios (SSP2-4.5 and SSP3-7.0), more likely than not to be exceeded
           under the low greenhouse gas emissions scenario (SSP1-2.6) and more likely than not to be reached under the very low greenhouse gas emissions scenario (SSP1-1.9). Furthermore, for the very low
           greenhouse gas emissions scenario (SSP1-1.9), it is more likely than not that global surface temperature would decline back to below 1.5°C toward the end of the 21st century, with a temporary
           overshoot of no more than 0.1°C above 1.5°C global warming.
      27   Overshoot: In this report, pathways that first exceed a specified global warming level (usually 1.5°C, by more than 0.1°C), and then return to or below that level again before the end of a specified
           period of time (e.g., before 2100). Sometimes the magnitude and likelihood of the overshoot is also characterized. The overshoot duration can vary from at least one decade up to several decades.

                                                                                                                                                                       Summary for Policymakers

Observed Impacts from Climate Change

B.1           Human-induced climate change, including more frequent and intense extreme events, has caused widespread adverse
              impacts and related losses and damages to nature and people, beyond natural climate variability. Some development and
              adaptation efforts have reduced vulnerability. Across sectors and regions the most vulnerable people and systems are ob-
              served to be disproportionately affected. The rise in weather and climate extremes has led to some irreversible impacts as
              natural and human systems are pushed beyond their ability to adapt. (high confidence) (Figure SPM.2) {TS B.1, Figure TS.5,                                                                            SPM
              1.3, 2.3, 2.4, 2.6, 3.3, 3.4, 3.5, 4.2, 4.3, 5.2, 5.12, 6.2, 7.2, 8.2, 9.6, 9.8, 9.10, 9.11, 10.4, 11.3, 12.3, 12.4, 13.10, 14.4, 14.5,
              15.3, 16.2, CCP1.2, CCP3.2, CCP4.1, CCP5.2, CCP6.2, CCP7.2, CCP7.3, CCB DISASTER, CCB EXTREMES, CCB ILLNESS, CCB

B.1.1         Widespread, pervasive impacts to ecosystems, people, settlements, and infrastructure have resulted from observed increases in the
              frequency and intensity of climate and weather extremes, including hot extremes on land and in the ocean, heavy precipitation events,
              drought and fire weather (high confidence). Increasingly since AR5, these observed impacts have been attributed28 to human-induced
              climate change particularly through increased frequency and severity of extreme events. These include increased heat-related human
              mortality (medium confidence), warm-water coral bleaching and mortality (high confidence), and increased drought-related tree
              mortality (high confidence). Observed increases in areas burned by wildfires have been attributed to human-induced climate change
              in some regions (medium to high confidence). Adverse impacts from tropical cyclones, with related losses and damages19, have
              increased due to sea level rise and the increase in heavy precipitation (medium confidence). Impacts in natural and human systems
              from slow-onset processes29 such as ocean acidification, sea level rise or regional decreases in precipitation have also been attributed
              to human induced climate change (high confidence). {1.3, 2.3, 2.4, 2.5, 3.2, 3.4, 3.5, 3.6, 4.2, 5.2, 5.4, 5.6, 5.12, 7.2, 9.6, 9.7, 9.8, 9.11,
              11.3, Box 11.1, Box 11.2, Table 11.9, 12.3, 12.4, 13.3, 13.5, 13.10, 14.2, 14.5, 15.7, 15.8, 16.2, CCP1.2, CCP2.2, Box CCP5.1, CCP7.3,
              CCB DISASTER, CCB EXTREME, CCB ILLNESS, WGI AR6 SPM.3, WGI AR6 9, WGI AR6 11.3–11.8, SROCC Chapter 4}

B.1.2         Climate change has caused substantial damages, and increasingly irreversible losses, in terrestrial, freshwater and coastal and open
              ocean marine ecosystems (high confidence). The extent and magnitude of climate change impacts are larger than estimated in previous
              assessments (high confidence). Widespread deterioration of ecosystem structure and function, resilience and natural adaptive capacity,
              as well as shifts in seasonal timing have occurred due to climate change (high confidence), with adverse socioeconomic consequences
              (high confidence). Approximately half of the species assessed globally have shifted polewards or, on land, also to higher elevations
              (very high confidence). Hundreds of local losses of species have been driven by increases in the magnitude of heat extremes (high
              confidence), as well as mass mortality events on land and in the ocean (very high confidence) and loss of kelp forests (high confidence).
              Some losses are already irreversible, such as the first species extinctions driven by climate change (medium confidence). Other impacts
              are approaching irreversibility such as the impacts of hydrological changes resulting from the retreat of glaciers, or the changes in
              some mountain (medium confidence) and Arctic ecosystems driven by permafrost thaw (high confidence). (Figure SPM.2a). { TS B.1,
              Figure TS.5, 2.3, 2.4, 3.4, 3.5, 4.2, 4.3, 4.5, 9.6, 10.4, 11.3, 12.3, 12.8, 13.3, 13.4, 13.10, 14.4, 14.5, 14.6, 15.3, 16.2, CCP1.2, CCP3.2,
              CCP4.1, CCP5.2, Figure CCP5.4, CCP6.1, CCP6.2, CCP7.2, CCP7.3, CCB EXTREMES, CCB ILLNESS, CCB MOVING PLATE, CCB NATURAL,
              CCB PALEO, CCB SLR, SROCC 2.3}

B.1.3         Climate change including increases in frequency and intensity of extremes have reduced food and water security, hindering efforts
              to meet Sustainable Development Goals (high confidence). Although overall agricultural productivity has increased, climate change
              has slowed this growth over the past 50 years globally (medium confidence), related negative impacts were mainly in mid- and low
              latitude regions but positive impacts occurred in some high latitude regions (high confidence). Ocean warming and ocean acidification
              have adversely affected food production from shellfish aquaculture and fisheries in some oceanic regions (high confidence). Increasing
              weather and climate extreme events have exposed millions of people to acute food insecurity30 and reduced water security, with the
              largest impacts observed in many locations and/or communities in Africa, Asia, Central and South America, Small Islands and the Arctic
              (high confidence). Jointly, sudden losses of food production and access to food compounded by decreased diet diversity have increased
              malnutrition in many communities (high confidence), especially for Indigenous Peoples, small-scale food producers and low-income
              households (high confidence), with children, elderly people and pregnant women particularly impacted (high confidence). Roughly half
              of the world’s population currently experience severe water scarcity for at least some part of the year due to climatic and non-climatic
              drivers (medium confidence). (Figure SPM.2b) {3.5, 4.3, 4.4, Box 4.1, 5.2, 5.4, 5.8, 5.9, 5.12, 7.1, 7.2, 9.8, 10.4, 11.3, 12.3, 13.5, 14.4,
              14.5, 15.3, 16.2, CCP5.2, CCP6.2}

28    Attribution is defined as the process of evaluating the relative contributions of multiple causal factors to a change or event with an assessment of confidence. {Annex II Glossary, CWGB ATTRIB}
29    Impacts of climate change are caused by slow onset and extreme events. Slow onset events are described among the climatic-impact drivers of the WGI AR6 and refer to the risks and impacts
      associated with e.g., increasing temperature means, desertification, decreasing precipitation, loss of biodiversity, land and forest degradation, glacial retreat and related impacts, ocean acidification,
      sea level rise and salinization (
30    Acute food insecurity can occur at any time with a severity that threatens lives, livelihoods or both, regardless of the causes, context or duration, as a result of shocks risking determinants of food
      security and nutrition, and used to assess the need for humanitarian action.

      Summary for Policymakers

      Impacts of climate change are observed in many ecosystems and human systems worldwide
      (a) Observed impacts of climate change on ecosystems
                                            Changes in                                    Species                              Changes in timing
                                       ecosystem structure                              range shifts                                (phenology)
                Ecosystems       Terrestrial Freshwater Ocean                Terrestrial Freshwater      Ocean           Terrestrial Freshwater Ocean

SPM                                                                                                                                                             Confidence
                                                                                                                                                                in attribution
                      Global                                                                                                                                    to climate change
                                                                                                                                                                     High or very high
                Central and                                                                                                                                          Evidence limited,
              South America                                                                                                                                          insufficient
                     Europe                                                                                                                                      na Not applicable

              North America
                Small Islands
                        Arctic                                                              /
                    Antarctic                                                                                                                                   to human systems
                                                                                                                                                                in panel (b)
       Mediterranean region
              Tropical forests                                  na                                       na                                          na              adverse
           Mountain regions                                     na                                       na                                          na
                      Deserts                     na            na                         na            na                             na           na              adverse
                                                                                                                                                                     and positive
        Biodiversity hotspots                                                                                                                        not             impacts

      (b) Observed impacts of climate change on human systems
                                              Impacts on                                             Impacts on                                            Impacts on
                                  water scarcity and food production                            health and wellbeing                         cities, settlements and infrastructure
                                                         Animal and Fisheries                                                               Inland   Flood/storm                Damages
                                            Agriculture/ livestock   yields and                   Heat,                                  flooding and induced      Damages        to key
                     Human        Water        crop      health and aquaculture     Infectious malnutrition   Mental                      associated damages in        to       economic
                    systems      scarcity   production productivity production       diseases   and other     health     Displacement      damages coastal areas infrastructure sectors


                 Australasia                                                                                                  not
                Central and                                                                                      not
              South America                                                                                   assessed
              North America
                Small Islands
                        Arctic                                                                     ¹

             Cities by the sea                                                                                   not
       Mediterranean region                                                                                      not
           Mountain regions                                                                                                                               na

      Figure SPM.2 | Observed global and regional impacts on ecosystems and human systems attributed to climate change. Confidence levels reflect uncertainty
      in attribution of the observed impact to climate change. Global assessments focus on large studies, multi-species, meta-analyses and large reviews. For that reason they can be
      assessed with higher confidence than regional studies, which may often rely on smaller studies that have more limited data. Regional assessments consider evidence on impacts
      across an entire region and do not focus on any country in particular.
      (a) Climate change has already altered terrestrial, freshwater and ocean ecosystems at global scale, with multiple impacts evident at regional and local scales where there is
      sufficient literature to make an assessment. Impacts are evident on ecosystem structure, species geographic ranges and timing of seasonal life cycles (phenology) (for methodology
      and detailed references to chapters and cross-chapter papers see SMTS.1 and SMTS.1.1).

                                                                                                                                                     Summary for Policymakers

(b) Climate change has already had diverse adverse impacts on human systems, including on water security and food production, health and well-being, and cities, settlements and
infrastructure. The + and – symbols indicate the direction of observed impacts, with a – denoting an increasing adverse impact and a ± denoting that, within a region or globally, both
adverse and positive impacts have been observed (e.g., adverse impacts in one area or food item may occur with positive impacts in another area or food item). Globally, ‘–’ denotes an
overall adverse impact; ‘Water scarcity’ considers, e.g., water availability in general, groundwater, water quality, demand for water, drought in cities. Impacts on food production were
assessed by excluding non-climatic drivers of production increases; Global assessment for agricultural production is based on the impacts on global aggregated production; ‘Reduced
animal and livestock health and productivity’ considers, e.g., heat stress, diseases, productivity, mortality; ‘Reduced fisheries yields and aquaculture production’ includes marine and
freshwater fisheries/production; ‘Infectious diseases’ include, e.g., water-borne and vector-borne diseases; ‘Heat, malnutrition and other’ considers, e.g., human heat-related morbidity
and mortality, labour productivity, harm from wildfire, nutritional deficiencies; ‘Mental health’ includes impacts from extreme weather events, cumulative events, and vicarious or
anticipatory events; ‘Displacement’ assessments refer to evidence of displacement attributable to climate and weather extremes; ‘Inland flooding and associated damages’ considers,
e.g., river overflows, heavy rain, glacier outbursts, urban flooding; ‘Flood/storm induced damages in coastal areas’ include damages due to, e.g., cyclones, sea level rise, storm surges.
Damages by key economic sectors are observed impacts related to an attributable mean or extreme climate hazard or directly attributed. Key economic sectors include standard
classifications and sectors of importance to regions (for methodology and detailed references to chapters and cross-chapter papers see SMTS.1 and SMTS.1.2).

B.1.4       Climate change has adversely affected physical health of people globally (very high confidence) and mental health of people in the
            assessed regions (very high confidence). Climate change impacts on health are mediated through natural and human systems, including
            economic and social conditions and disruptions (high confidence). In all regions extreme heat events have resulted in human mortality
            and morbidity (very high confidence). The occurrence of climate-related food-borne and water-borne diseases has increased (very high
            confidence). The incidence of vector-borne diseases has increased from range expansion and/or increased reproduction of disease vectors
            (high confidence). Animal and human diseases, including zoonoses, are emerging in new areas (high confidence). Water and food-borne
            disease risks have increased regionally from climate-sensitive aquatic pathogens, including Vibrio spp. (high confidence), and from toxic
            substances from harmful freshwater cyanobacteria (medium confidence). Although diarrheal diseases have decreased globally, higher
            temperatures, increased rain and flooding have increased the occurrence of diarrheal diseases, including cholera (very high confidence)
            and other gastrointestinal infections (high confidence). In assessed regions, some mental health challenges are associated with increasing
            temperatures (high confidence), trauma from weather and climate extreme events (very high confidence), and loss of livelihoods and culture
            (high confidence). Increased exposure to wildfire smoke, atmospheric dust, and aeroallergens have been associated with climate-sensitive
            cardiovascular and respiratory distress (high confidence). Health services have been disrupted by extreme events such as floods (high
            confidence). {4.3, 5.12, 7.2, Box 7.3, 8.2, 8.3, Box 8.6, Figure 8.10, 9.10, Figure 9.33, Figure 9.34, 10.4, 11.3, 12.3, 13.7, 14.4, 14.5,
            Figure 14.8, 15.3, 16.2, CCP5.2, Table CCP5.1, CCP6.2, Figure CCP6.3, Table CCB ILLNESS.1}

B.1.5       In urban settings, observed climate change has caused impacts on human health, livelihoods and key infrastructure (high confidence).
            Multiple climate and non-climate hazards impact cities, settlements and infrastructure and sometimes coincide, magnifying damage
            (high confidence). Hot extremes including heatwaves have intensified in cities (high confidence), where they have also aggravated
            air pollution events (medium confidence) and limited functioning of key infrastructure (high confidence). Observed impacts are
            concentrated amongst the economically and socially marginalized urban residents, e.g., in informal settlements (high confidence).
            Infrastructure, including transportation, water, sanitation and energy systems have been compromised by extreme and slow-onset
            events, with resulting economic losses, disruptions of services and impacts to well-being (high confidence). {4.3, 6.2, 7.1, 7.2, 9.9, 10.4,
            11.3, 12.3, 13.6, 14.5, 15.3, CCP2.2, CCP4.2, CCP5.2}

B.1.6       Overall adverse economic impacts attributable to climate change, including slow-onset and extreme weather events, have been
            increasingly identified (medium confidence). Some positive economic effects have been identified in regions that have benefited from
            lower energy demand as well as comparative advantages in agricultural markets and tourism (high confidence). Economic damages
            from climate change have been detected in climate-exposed sectors, with regional effects to agriculture, forestry, fishery, energy,
            and tourism (high confidence), and through outdoor labour productivity (high confidence). Some extreme weather events, such as
            tropical cyclones, have reduced economic growth in the short-term (high confidence). Non-climatic factors including some patterns
            of settlement, and siting of infrastructure have contributed to the exposure of more assets to extreme climate hazards increasing the
            magnitude of the losses (high confidence). Individual livelihoods have been affected through changes in agricultural productivity,
            impacts on human health and food security, destruction of homes and infrastructure, and loss of property and income, with adverse
            effects on gender and social equity (high confidence). {3.5, 4.2, 5.12, 6.2, 7.2, 8.2, 9.6, 10.4, 13.10, 14.5, Box 14.6, 16.2, Table 16.5,
            18.3, CCP6.2, CCB GENDER, CWGB ECONOMICS}

B.1.7       Climate change is contributing to humanitarian crises where climate hazards interact with high vulnerability (high confidence). Climate
            and weather extremes are increasingly driving displacement in all regions (high confidence), with Small Island States disproportionately
            affected (high confidence). Flood and drought-related acute food insecurity and malnutrition have increased in Africa (high confidence)
            and Central and South America (high confidence). While non-climatic factors are the dominant drivers of existing intrastate violent
            conflicts, in some assessed regions extreme weather and climate events have had a small, adverse impact on their length, severity or
            frequency, but the statistical association is weak (medium confidence). Through displacement and involuntary migration from extreme
            weather and climate events, climate change has generated and perpetuated vulnerability (medium confidence). {4.2, 4.3, 5.4, 7.2, 9.8,
            Box 9.9, Box 10.4, 12.3, 12.5, 16.2, CCB DISASTER, CCB MIGRATE}

      Summary for Policymakers

      Vulnerability and Exposure of Ecosystems and People

      B.2           Vulnerability of ecosystems and people to climate change differs substantially among and within regions (very high
                    confidence), driven by patterns of intersecting socioeconomic development, unsustainable ocean and land use, inequity,
                    marginalization, historical and ongoing patterns of inequity such as colonialism, and governance31 (high confidence).
                    Approximately 3.3 to 3.6 billion people live in contexts that are highly vulnerable to climate change (high confidence).
SPM                 A high proportion of species is vulnerable to climate change (high confidence). Human and ecosystem vulnerability are
                    interdependent (high confidence). Current unsustainable development patterns are increasing exposure of ecosystems
                    and people to climate hazards (high confidence). {2.3, 2.4, 3.5, 4.3, 6.2, 8.2, 8.3, 9.4, 9.7, 10.4, 12.3, 14.5, 15.3, CCP5.2,
                    CCP6.2, CCP7.3, CCP7.4, CCB GENDER}

      B.2.1         Since AR5 there is increasing evidence that degradation and destruction of ecosystems by humans increases the vulnerability of
                    people (high confidence). Unsustainable land-use and land cover change, unsustainable use of natural resources, deforestation, loss
                    of biodiversity, pollution, and their interactions, adversely affect the capacities of ecosystems, societies, communities and individuals
                    to adapt to climate change (high confidence). Loss of ecosystems and their services has cascading and long-term impacts on people
                    globally, especially for Indigenous Peoples and local communities who are directly dependent on ecosystems, to meet basic needs (high
                    confidence). {2.3, 2.5, 2.6, 3.5, 3.6, 4.2, 4.3, 4.6, 5.1, 5.4, 5.5, 5.7, 5.8, 7.2, 8.1, 8.2, 8.3, 8.4, 8.5, 9.6, 10.4, 11.3, 12.2, 12.5, 13.8, 14.4,
                    14.5, 15.3, CCP1.2, CCP1.3, CCP2.2, CCP3, CCP4.3, CCP5.2, CCP6.2, CCP7.2, CCP7.3, CCP7.4, CCB ILLNESS, CCB MOVING PLATE, CCB

      B.2.2         Non-climatic human-induced factors exacerbate current ecosystem vulnerability to climate change (very high confidence). Globally,
                    and even within protected areas, unsustainable use of natural resources, habitat fragmentation, and ecosystem damage by pollutants
                    increase ecosystem vulnerability to climate change (high confidence). Globally, less than 15% of the land, 21% of the freshwater and
                    8% of the ocean are protected areas. In most protected areas, there is insufficient stewardship to contribute to reducing damage from,
                    or increasing resilience to, climate change (high confidence). {2.4, 2.5, 2.6, 3.4, 3.6, 4.2, 4.3, 5.8, 9.6, 11.3, 12.3, 13.3, 13.4, 14.5, 15.3,
                    CCP1.2, Figure CCP1.15, CCP2.1, CCP2.2, CCP4.2, CCP5.2, CCP6.2, CCP7.2, CCP7.3, CCB NATURAL}

      B.2.3         Future vulnerability of ecosystems to climate change will be strongly influenced by the past, present and future development of human
                    society, including from overall unsustainable consumption and production, and increasing demographic pressures, as well as persistent
                    unsustainable use and management of land, ocean, and water (high confidence). Projected climate change, combined with non-climatic
                    drivers, will cause loss and degradation of much of the world’s forests (high confidence), coral reefs and low-lying coastal wetlands
                    (very high confidence). While agricultural development contributes to food security, unsustainable agricultural expansion, driven in part
                    by unbalanced diets32, increases ecosystem and human vulnerability and leads to competition for land and/or water resources (high
                    confidence). {2.2, 2.3, 2.4, 2.6, 3.4, 3.5, 3.6, 4.3, 4.5, 5.6, 5.12, 5.13, 7.2, 12.3, 13.3, 13.4, 13.10, 14.5, CCP1.2, CCP2.2, CCP5.2, CCP6.2,
                    CCP7.2, CCP7.3, CCB HEALTH, CCB NATURAL}

      B.2.4         Regions and people with considerable development constraints have high vulnerability to climatic hazards (high confidence). Global
                    hotspots of high human vulnerability are found particularly in West-, Central- and East Africa, South Asia, Central and South America,
                    Small Island Developing States and the Arctic (high confidence). Vulnerability is higher in locations with poverty, governance challenges
                    and limited access to basic services and resources, violent conflict and high levels of climate-sensitive livelihoods (e.g., smallholder
                    farmers, pastoralists, fishing communities) (high confidence). Between 2010–2020, human mortality from floods, droughts and storms
                    was 15 times higher in highly vulnerable regions, compared to regions with very low vulnerability (high confidence). Vulnerability
                    at different spatial levels is exacerbated by inequity and marginalization linked to gender, ethnicity, low income or combinations
                    thereof (high confidence), especially for many Indigenous Peoples and local communities (high confidence). Present development
                    challenges causing high vulnerability are influenced by historical and ongoing patterns of inequity such as colonialism, especially for
                    many Indigenous Peoples and local communities (high confidence). {4.2, 5.12, 6.2, 6.4, 7.1, 7.2, Box 7.1, 8.2, 8.3, Box 8.4, Figure 8.6,
                    Box 9.1, 9.4, 9.7, 9.9, 10.3, 10.4, 10.6, 12.3, 12.5, Box 13.2, 14.4, 15.3, 15.6, 16.2, CCP6.2, CCP7.4}

      B.2.5         Future human vulnerability will continue to concentrate where the capacities of local, municipal and national governments,
                    communities and the private sector are least able to provide infrastructures and basic services (high confidence). Under the global
                    trend of urbanization, human vulnerability will also concentrate in informal settlements and rapidly growing smaller settlements (high

      31    Governance: The structures, processes and actions through which private and public actors interact to address societal goals. This includes formal and informal institutions and the associated norms,
            rules, laws and procedures for deciding, managing, implementing and monitoring policies and measures at any geographic or political scale, from global to local.
      32    Balanced diets feature plant-based foods, such as those based on coarse grains, legumes fruits and vegetables, nuts and seeds, and animal-source foods produced in resilient, sustainable and
            low-greenhouse gas emissions systems, as described in SRCCL.

                                                                                                                       Summary for Policymakers

        confidence). In rural areas vulnerability will be heightened by compounding processes including high emigration, reduced habitability and
        high reliance on climate-sensitive livelihoods (high confidence). Key infrastructure systems including sanitation, water, health, transport,
        communications and energy will be increasingly vulnerable if design standards do not account for changing climate conditions (high
        confidence). Vulnerability will also rapidly rise in low-lying Small Island Developing States and atolls in the context of sea level rise and
        in some mountain regions, already characterised by high vulnerability due to high dependence on climate-sensitive livelihoods, rising
        population displacement, the accelerating loss of ecosystem services and limited adaptive capacities (high confidence). Future exposure
        to climatic hazards is also increasing globally due to socioeconomic development trends including migration, growing inequality and             SPM
        urbanization (high confidence). {4.5, 5.5, 6.2, 7.2, 8.3, 9.9, 9.11, 10.3, 10.4, 12.3, 12.5, 13.6, 14.5, 15.3, 15.4, 16.5, CCP2.3, CCP4.3,
        CCP5.2, CCP5.3, CCP5.4, CCP6.2, CCB MIGRATE}

Risks in the near term (2021–2040)

B.3     Global warming, reaching 1.5°C in the near-term, would cause unavoidable increases in multiple climate hazards and
        present multiple risks to ecosystems and humans (very high confidence). The level of risk will depend on concurrent near-
        term trends in vulnerability, exposure, level of socioeconomic development and adaptation (high confidence). Near-term
        actions that limit global warming to close to 1.5°C would substantially reduce projected losses and damages related to
        climate change in human systems and ecosystems, compared to higher warming levels, but cannot eliminate them all
        (very high confidence). (Figure SPM.3, Box SPM.1) {16.4, 16.5, 16.6, CCP1.2, CCP5.3, CCB SLR, WGI AR6 SPM B1.3, WGI AR6
        Table SPM.1}

B.3.1   Near-term warming and increased frequency, severity and duration of extreme events will place many terrestrial, freshwater, coastal
        and marine ecosystems at high or very high risks of biodiversity loss (medium to very high confidence, depending on ecosystem).
        Near-term risks for biodiversity loss are moderate to high in forest ecosystems (medium confidence), kelp and seagrass ecosystems
        (high to very high confidence), and high to very high in Arctic sea-ice and terrestrial ecosystems (high confidence) and warm-water
        coral reefs (very high confidence). Continued and accelerating sea level rise will encroach on coastal settlements and infrastructure
        (high confidence) and commit low-lying coastal ecosystems to submergence and loss (medium confidence). If trends in urbanisation in
        exposed areas continue, this will exacerbate the impacts, with more challenges where energy, water and other services are constrained
        (medium confidence). The number of people at risk from climate change and associated loss of biodiversity will progressively increase
        (medium confidence). Violent conflict and, separately, migration patterns, in the near-term will be driven by socioeconomic conditions
        and governance more than by climate change (medium confidence). (Figure SPM.3) {2.5, 3.4, 4.6, 6.2, 7.3, 8.7, 9.2, 9.9, 11.6, 12.5, 13.6,
        13.10, 14.6, 15.3, 16.5, 16.6, CCP1.2, CCP2.1, CCP2.2, CCP5.3, CCP6.2, CCP6.3, CCB MIGRATE, CCB SLR}

B.3.2   In the near term, climate-associated risks to natural and human systems depend more strongly on changes in their vulnerability and
        exposure than on differences in climate hazards between emissions scenarios (high confidence). Regional differences exist, and risks
        are highest where species and people exist close to their upper thermal limits, along coastlines, in close association with ice or seasonal
        rivers (high confidence). Risks are also high where multiple non-climate drivers persist or where vulnerability is otherwise elevated
        (high confidence). Many of these risks are unavoidable in the near-term, irrespective of emissions scenario (high confidence). Several
        risks can be moderated with adaptation (high confidence). (Figure SPM.3, Section C) {2.5, 3.3, 3.4, 4.5, 6.2, 7.1, 7.3, 8.2, 11.6, 12.4,
        13.6, 13.7, 13.10, 14.5, 16.4, 16.5, CCP2.2, CCP4.3, CCP5.3, CCB SLR, WGI AR6 Table SPM.1}

B.3.3   Levels of risk for all Reasons for Concern (RFC) are assessed to become high to very high at lower global warming levels than in
        AR5 (high confidence). Between 1.2°C and 4.5°C global warming level very high risks emerge in all five RFCs compared to just two
        RFCs in AR5 (high confidence). Two of these transitions from high to very high risk are associated with near-term warming: risks to
        unique and threatened systems at a median value of 1.5 [1.2 to 2.0] °C (high confidence) and risks associated with extreme weather
        events at a median value of 2.0 [1.8 to 2.5] °C (medium confidence). Some key risks contributing to the RFCs are projected to lead to
        widespread, pervasive, and potentially irreversible impacts at global warming levels of 1.5–2°C if exposure and vulnerability are high
        and adaptation is low (medium confidence). Near-term actions that limit global warming to close to 1.5°C would substantially reduce
        projected losses and damages related to climate change in human systems and ecosystems, compared to higher warming levels, but
        cannot eliminate them all (very high confidence). (Figure SPM.3b) {16.5, 16.6, CCB SLR}

      Summary for Policymakers

      Mid to Long-term Risks (2041–2100)

      B.4           Beyond 2040 and depending on the level of global warming, climate change will lead to numerous risks to natural and
                    human systems (high confidence). For 127 identified key risks, assessed mid- and long-term impacts are up to multiple
                    times higher than currently observed (high confidence). The magnitude and rate of climate change and associated risks
                    depend strongly on near-term mitigation and adaptation actions, and projected adverse impacts and related losses and
SPM                 damages escalate with every increment of global warming (very high confidence). (Figure SPM.3) {2.5, 3.4, 4.4, 5.2, 6.2,
                    7.3, 8.4, 9.2, 10.2, 11.6, 12.4, 13.2, 13.3, 13.4, 13.5, 13.6, 13.7, 13.8, 14.6, 15.3, 16.5, 16.6, CCP1.2, CCP2.2, CCP3.3, CCP4.3,
                    CCP5.3, CCP6.3, CCP7.3}

      B.4.1         Biodiversity loss and degradation, damages to and transformation of ecosystems are already key risks for every region due to past
                    global warming and will continue to escalate with every increment of global warming (very high confidence). In terrestrial ecosystems,
                    3 to 14% of species assessed33 will likely face very high risk of extinction34 at global warming levels of 1.5°C, increasing up to 3 to
                    18% at 2°C, 3 to 29% at 3°C, 3 to 39% at 4°C, and 3 to 48% at 5°C. In ocean and coastal ecosystems, risk of biodiversity loss ranges
                    between moderate and very high by 1.5°C global warming level and is moderate to very high by 2°C but with more ecosystems at high
                    and very high risk (high confidence), and increases to high to very high across most ocean and coastal ecosystems by 3°C (medium
                    to high confidence, depending on ecosystem). Very high extinction risk for endemic species in biodiversity hotspots is projected to at
                    least double from 2% between 1.5°C and 2°C global warming levels and to increase at least tenfold if warming rises from 1.5°C to
                    3°C (medium confidence). (Figure SPM.3c, d, f) {2.4, 2.5, 3.4, 3.5,12.3, 12.5, Table 12.6, 13.4, 13.10, 16.4, 16.6, CCP1.2, Figure CCP1.6,
                    Figure CCP1.7, CCP5.3, CCP6.3, CCB PALEO}

      B.4.2         Risks in physical water availability and water-related hazards will continue to increase by the mid- to long-term in all assessed regions,
                    with greater risk at higher global warming levels (high confidence). At approximately 2°C global warming, snowmelt water availability
                    for irrigation is projected to decline in some snowmelt dependent river basins by up to 20%, and global glacier mass loss of 18 ± 13%
                    is projected to diminish water availability for agriculture, hydropower, and human settlements in the mid- to long-term, with these
                    changes projected to double with 4°C global warming (medium confidence). In Small Islands, groundwater availability is threatened by
                    climate change (high confidence). Changes to streamflow magnitude, timing and associated extremes are projected to adversely impact
                    freshwater ecosystems in many watersheds by the mid- to long-term across all assessed scenarios (medium confidence). Projected
                    increases in direct flood damages are higher by 1.4 to 2 times at 2°C and 2.5 to 3.9 times at 3°C compared to 1.5°C global warming
                    without adaptation (medium confidence). At global warming of 4°C, approximately 10% of the global land area is projected to face
                    increases in both extreme high and low river flows in the same location, with implications for planning for all water use sectors (medium
                    confidence). Challenges for water management will be exacerbated in the near, mid and long term, depending on the magnitude, rate
                    and regional details of future climate change and will be particularly challenging for regions with constrained resources for water
                    management (high confidence). {2.3, 4.4, 4.5, Box 4.2, Figure 4.20, 15.3, CCP5.3, CCB DISASTER, SROCC 2.3}

      B.4.3         Climate change will increasingly put pressure on food production and access, especially in vulnerable regions, undermining food security
                    and nutrition (high confidence). Increases in frequency, intensity and severity of droughts, floods and heatwaves, and continued sea
                    level rise will increase risks to food security (high confidence) in vulnerable regions from moderate to high between 1.5°C and 2°C
                    global warming level, with no or low levels of adaptation (medium confidence). At 2°C or higher global warming level in the mid-term,
                    food security risks due to climate change will be more severe, leading to malnutrition and micro-nutrient deficiencies, concentrated
                    in Sub-Saharan Africa, South Asia, Central and South America and Small Islands (high confidence). Global warming will progressively
                    weaken soil health and ecosystem services such as pollination, increase pressure from pests and diseases, and reduce marine animal
                    biomass, undermining food productivity in many regions on land and in the ocean (medium confidence). At 3°C or higher global warming
                    level in the long term, areas exposed to climate-related hazards will expand substantially compared with 2°C or lower global warming
                    level (high confidence), exacerbating regional disparity in food security risks (high confidence). (Figure SPM.3) {1.1, 3.3, 4.5, 5.2, 5.4, 5.5,
                    5.8, 5.9, 5.12, 7.3, 8.3, 9.11, 13.5, 15.3, 16.5, 16.6, CCB MOVING PLATE, CCB SLR}

      33    Numbers of species assessed are in the tens of thousands globally.
      34    The term ‘very high risks of extinction’ is used here consistently with the IUCN categories and criteria and equates with ‘critically endangered’.

                                                                                                                                                               Summary for Policymakers

B.4.4        Climate change and related extreme events will significantly increase ill health and premature deaths from the near- to long-term (high
             confidence). Globally, population exposure to heatwaves will continue to increase with additional warming, with strong geographical
             differences in heat-related mortality without additional adaptation (very high confidence). Climate-sensitive food-borne, water-borne,
             and vector-borne disease risks are projected to increase under all levels of warming without additional adaptation (high confidence). In
             particular, dengue risk will increase with longer seasons and a wider geographic distribution in Asia, Europe, Central and South America
             and sub-Saharan Africa, potentially putting additional billions of people at risk by the end of the century (high confidence). Mental health
             challenges, including anxiety and stress, are expected to increase under further global warming in all assessed regions, particularly for                                                    SPM
             children, adolescents, elderly, and those with underlying health conditions (very high confidence). {4.5, 5.12, Box 5.10, 7.3, Figure 7.9,
             8.4, 9.10, Figure 9.32, Figure 9.35, 10.4, Figure 10.11, 11.3, 12.3, Figure 12.5, Figure 12.6, 13.7, Figure 13.23, Figure 13.24, 14.5, 15.3,

B.4.5        Climate change risks to cities, settlements and key infrastructure will rise rapidly in the mid- and long-term with further global
             warming, especially in places already exposed to high temperatures, along coastlines, or with high vulnerabilities (high confidence).
             Globally, population change in low-lying cities and settlements will lead to approximately a billion people projected to be at risk
             from coastal-specific climate hazards in the mid-term under all scenarios, including in Small Islands (high confidence). The population
             potentially exposed to a 100-year coastal flood is projected to increase by about 20% if global mean sea level rises by 0.15 m relative
             to 2020 levels; this exposed population doubles at a 0.75 m rise in mean sea level and triples at 1.4 m without population change
             and additional adaptation (medium confidence). Sea level rise poses an existential threat for some Small Islands and some low-lying
             coasts (medium confidence). By 2100 the value of global assets within the future 1-in-100 year coastal floodplains is projected to
             be between US$7.9 and US$12.7 trillion (2011 value) under RCP4.5, rising to between US$8.8 and US$14.2 trillion under RCP8.5
             (medium confidence). Costs for maintenance and reconstruction of urban infrastructure, including building, transportation, and energy
             will increase with global warming level (medium confidence), the associated functional disruptions are projected to be substantial
             particularly for cities, settlements and infrastructure located on permafrost in cold regions and on coasts (high confidence). {6.2, 9.9,
             10.4, 13.6, 13.10, 15.3, 16.5, CCP2.1, CCP2.2, CCP5.3, CCP6.2, CCB SLR, SROCC 2.3, SROCC CCB9}

B.4.6        Projected estimates of global aggregate net economic damages generally increase non-linearly with global warming levels (high
             confidence).35 The wide range of global estimates, and the lack of comparability between methodologies, does not allow for identification
             of a robust range of estimates (high confidence). The existence of higher estimates than assessed in AR5 indicates that global aggregate
             economic impacts could be higher than previous estimates (low confidence).36 Significant regional variation in aggregate economic
             damages from climate change is projected (high confidence) with estimated economic damages per capita for developing countries
             often higher as a fraction of income (high confidence). Economic damages, including both those represented and those not represented
             in economic markets, are projected to be lower at 1.5°C than at 3°C or higher global warming levels (high confidence). {4.4, 9.11, 11.5,
             13.10, Box 14.6, 16.5, CWGB ECONOMIC}

B.4.7        In the mid- to long-term, displacement will increase with intensification of heavy precipitation and associated flooding, tropical cyclones,
             drought and, increasingly, sea level rise (high confidence). At progressive levels of warming, involuntary migration from regions with
             high exposure and low adaptive capacity would occur (medium confidence). Compared to other socioeconomic factors the influence of
             climate on conflict is assessed as relatively weak (high confidence). Along long-term socioeconomic pathways that reduce non-climatic
             drivers, risk of violent conflict would decline (medium confidence). At higher global warming levels, impacts of weather and climate
             extremes, particularly drought, by increasing vulnerability will increasingly affect violent intrastate conflict (medium confidence). {TS
             B.7.4, 7.3, 16.5, CCB MIGRATE }

35   The assessment found estimated rates of increase in projected global economic damages that were both greater than linear and less than linear as global warming level increases. There is evidence
     that some regions could benefit from low levels of warming (high confidence). {CWGB ECONOMIC}
36   Low confidence assigned due to the assessed lack of comparability and robustness of global aggregate economic damage estimates. {CWGB ECONOMIC}

        Summary for Policymakers

        Global and regional risks for increasing levels of global warming

        (a) Global surface temperature change                                                                                                          (b) Reasons for Concern (RFC)
            Increase relative to the period 1850–1900                                                                                                      Impact and risk assessments assuming low to no adaptation
                                          5                                                                                                                                                                                                       Risk/impact
SPM                                                      Projections for different scenarios
                                                                                                                                                                                                                                                         Very high
                                                         SSP1-2.6 (shade representing very likely range)
                                               4                                                                                                                                                                                                         Moderate
                                                         SSP3-7.0 (shade representing very likely range)


                                                                                                                                                                                                                                                   Transition range

                                                                                                                                                                                                                                                  Confidence level
                                                                                                                                                                                                                                                  assigned to

                                               2                                                                                                                                                                                                  range




                                                                                                                                                                                                                                                   Low          Very high


                                                                                                                                                                                                                                                  Historical average

                                                                                                                                                                   •••• ••••
                                                                                                                                                                                                                                                  temperature increase


                                                                                                                                                                                                                                                  in 2011–2020 was
                                                                                                                                                                                                                                                  1.09°C (dashed line)
                                                                                                                                                                                                                                                  range 0.95–1.20°C
                                                1950                         2000                           2050                          2100                 RFC1     RFC2      RFC3       RFC4     RFC5
                                                                                                                                                            Unique and Extreme Distribution Global Large scale
                                                                                                                                                            threatened weather of impacts aggregate singular
                                                                                                                                                              systems   events              impacts  events

        (c) Impacts and risks to terrestrial                                                        5°C                                          (d) Impacts and risks 5°C
               and freshwater ecosystems                                                                                                             to ocean ecosystems

      Global surface temperature change (°C)











                                                               •• •••

                                                                                                                                                                 •••• •••






                                                       Biodiversity     Structure      Tree                 Wildfire          Carbon                    Warm water              Kelp            Seagrass             Epipelagic          Rocky            Salt
                                                           loss          change       mortality             increase           loss                       corals               forests          meadows                                  shores          marshes

        (e) Climate sensitive health outcomes under three adaptation scenarios
                                                             Heat-related morbidity                                                                                                        Dengue and other diseases carried
                                                                 and mortality                    Ozone-related mortality *                                  Malaria                        by species of Aedes mosquitoes
      Global surface temperature change (°C)

                                                4                                                                                                                                                                            Scenario narratives
                                                                                                                                                                                                                                          Limited adaptation:
                                                                                                                                                                                                                                          Failure to proactively adapt;
                                                3                                                                                                                                                                                         low investment in health



                                                2                                                                                                                                                                                         Incomplete adaptation:


                                                                                                                                                                                                                                          Incomplete adaptation

                                                                                                                                                  •• ••••



                                                                                                                                                                                                                                          planning; moderate

                                                                                                                                                                                                  ••• ••••

                                                                                                                                                                                                                                          investment in health systems







                                                                                                                                                                                                                                          Proactive adaptation:
                                                                                                                                                                                                                                          Proactive adaptive
                                                0                                                                                                                                                                                         management; higher
                                                        Limited Incomplete Proactive     Limited Incomplete Proactive     Limited Incomplete Proactive     Limited Incomplete Proactive                                                   investment in health systems
                                                       adaptation adaptation adaptation adaptation adaptation adaptation adaptation adaptation adaptation adaptation adaptation adaptation

           * Mortality projections include demographic trends but do not include future efforts to improve air quality that reduce ozone concentrations.

                                                                                                                                                                                       Summary for Policymakers

(f) Examples of regional key risks

                                                                                                   Global surface temperature change (°C)
   Absence of risk diagrams does not imply absence of risks within a
   region. The development of synthetic diagrams for Small Islands, Asia and Central and
   South America was limited due to the paucity of adequately downscaled climate projections,                                               3

   with uncertainty in the direction of change, the diversity of climatologies and socioeconomic
   contexts across countries within a region, and the resulting few numbers of impact and risk

   projections for different warming levels.                                                                                                2

                                                                                                                                                                                                             ••• •• •


                                                                                                                                                                                            ••• ••

                                                                                                                                                                         ••• •••
   The risks listed are of at least medium confidence level:
   Small - Loss of terrestrial, marine and coastal biodiversity and ecosystem services

 Islands - Loss of lives and assets, risk to food security and economic disruption due to
           destruction of settlements and infrastructure
         - Economic decline and livelihood failure of fisheries, agriculture, tourism and from                                              0
                                                                                                                                                        Food    Biodiversity       Mortality and   Delayed
           biodiversity loss from traditional agroecosystems                                                                                       production       and               morbidity   impacts of
         - Reduced habitability of reef and non-reef islands leading to increased displacement                                                     from crops, ecosystems          from heat and sea level
         - Risk to water security in almost every small island                                                                                    fisheries and  in Africa                        rise in the
                                                                                                                                                                                      infectious Mediterranean
                                                                                                                                                     livestock                          disease
          - Climate-sensitive mental health outcomes, human mortality and morbidity due                                                              in Africa                         in Africa
 North                                                                                                                                      4

                                                                                                   Global surface temperature change (°C)
            to increasing average temperature, weather and climate extremes, and
America     compound climate hazards
          - Risk of degradation of marine, coastal and terrestrial ecosystems, including loss

            of biodiversity, function, and protective services                                                                              3


          - Risk to freshwater resources with consequences for ecosystems, reduced surface


            water availability for irrigated agriculture, other human uses, and degraded
            water quality                                                                                                                   2


                                                                                                                                                                                                             •• ••
          - Risk to food and nutritional security through changes in agriculture, livestock,

                                                                                                                                                                                            ••• •••
            hunting, fisheries, and aquaculture productivity and access                                                                     1.5
          - Risks to well-being, livelihoods and economic activities from cascading and                                                     1


            compounding climate hazards, including risks to coastal cities, settlements and
            infrastructure from sea level rise
 Europe - Risks to people, economies and infrastructures due to coastal and inland flooding                                                     Water quality Health and Water scarcity       Coastal     Heat stress,
        - Stress and mortality to people due to increasing temperatures and heat extremes                                                            and       wellbeing     to people in flooding to      mortality
                                                                                                                                                 availability    in the     southeastern       people         and
        - Marine and terrestrial ecosystems disruptions                                                                                            in the     Mediterranean
        - Water scarcity to multiple interconnected sectors                                                                                     Mediterranean                   Europe          and        morbidity
                                                                                                                                                                                          infrastructures to people
        - Losses in crop production, due to compound heat and dry conditions, and extreme                                                                                                    in Europe     in Europe
                                                                                                   Global surface temperature change (°C)

 Central - Risk to water security
    and - Severe health effects due to increasing epidemics, in particular vector-borne


  South diseases
America - Coral reef ecosystems degradation due to coral bleaching
         - Risk to food security due to frequent/extreme droughts


         - Damages to life and infrastructure due to floods, landslides, sea level rise, storm

           surges and coastal erosion                                                                                                       1.5                          ••••••


    Aus- - Degradation of tropical shallow coral reefs and associated biodiversity and

            ecosystem service values
          - Loss of human and natural systems in low-lying coastal areas due to sea level rise
          - Impact on livelihoods and incomes due to decline in agricultural production                                                     0
          - Increase in heat-related mortality and morbidity for people and wildlife                                                               Loss and       Cascading          Reduced         Costs and       Lyme
                                                                                                                                                degradation of impacts on           viability of      damages      disease in
          - Loss of alpine biodiversity in Australia due to less snow                                                                            coral reefs in   cities and         tourism-         related to     North
                                                                                                                                                   Australia     settlements          related maintenance and America
                                                                                                                                                                                    activities in reconstruction of under
    Asia - Urban infrastructure damage and impacts on human well-being and health due                                                                           in Australasia         North       transportation incomplete
           to flooding, especially in coastal cities and settlements                                                                                                                 America infrastructure in adaptation
                                                                                                                                                                                                   North America scenario
         - Biodiversity loss and habitat shifts as well as associated disruptions in
           dependent human systems across freshwater, land, and ocean ecosystems
                                                                                                   Global surface temperature change (°C)

         - More frequent, extensive coral bleaching and subsequent coral mortality

           induced by ocean warming and acidification, sea level rise, marine heat waves                                                                                                                                       ••
           and resource extraction
         - Decline in coastal fishery resources due to sea level rise, decrease in                                                          3
           precipitation in some parts and increase in temperature

         - Risk to food and water security due to increased temperature extremes, rainfall
           variability and drought                                                                                                          2



  Africa - Species extinction and reduction or irreversible loss of ecosystems and their


           services, including freshwater, land and ocean ecosystems

         - Risk to food security, risk of malnutrition (micronutrient deficiency), and loss of
           livelihood due to reduced food production from crops, livestock and fisheries
         - Risks to marine ecosystem health and to livelihoods in coastal communities                                                       0
         - Increased human mortality and morbidity due to increased heat and infectious                                                              Sea-ice     Changes in        Costs                Sea-ice         Changes
                                                                                                                                                   ecosystems fisheries catch and losses              dependent           in krill
           diseases (including vector-borne and diarrhoeal diseases)                                                                              from sea-ice for Pollock        for key             ecosystems        fisheries
         - Reduced economic output and growth, and increased inequality and poverty rates                                                           change in        and      infrastructure             in the           in the
                                                                                                                                                    the Arctic   Pacific Cod   in the Arctic           Antarctic        Antarctic
         - Increased risk to water and energy security due to drought and heat                                                                                  in the Arctic

Figure SPM.3 | Synthetic diagrams of global and sectoral assessments and examples of regional key risks. Diagrams show the change in the levels of impacts and
risks assessed for global warming of 0–5°C global surface temperature change relative to pre-industrial period (1850–1900) over the range.

      Summary for Policymakers

      (a) Global surface temperature changes in °C relative to 1850–1900. These changes were obtained by combining CMIP6 model simulations with observational constraints based
      on past simulated warming, as well as an updated assessment of equilibrium climate sensitivity (Box SPM.1). Changes relative to 1850–1900 based on 20-year averaging periods
      are calculated by adding 0.85°C (the observed global surface temperature increase from 1850–1900 to 1995–2014) to simulated changes relative to 1995–2014. Very likely ranges
      are shown for SSP1-2.6 and SSP3-7.0 (WGI AR6 Figure SPM.8). Assessments were carried out at the global scale for (b), (c), (d) and (e).
      (b) The Reasons for Concern (RFC) framework communicates scientific understanding about accrual of risk for five broad categories. Diagrams are shown for each RFC, assuming
      low to no adaptation (i.e., adaptation is fragmented, localized and comprises incremental adjustments to existing practices). However, the transition to a very high risk level has an
      emphasis on irreversibility and adaptation limits. Undetectable risk level (white) indicates no associated impacts are detectable and attributable to climate change; moderate risk
SPM   (yellow) indicates associated impacts are both detectable and attributable to climate change with at least medium confidence, also accounting for the other specific criteria for key
      risks; high risk (red) indicates severe and widespread impacts that are judged to be high on one or more criteria for assessing key risks; and very high risk level (purple) indicates
      very high risk of severe impacts and the presence of significant irreversibility or the persistence of climate-related hazards, combined with limited ability to adapt due to the nature
      of the hazard or impacts/risks. The horizontal line denotes the present global warming of 1.09°C which is used to separate the observed, past impacts below the line from the future
      projected risks above it. RFC1: Unique and threatened systems: ecological and human systems that have restricted geographic ranges constrained by climate-related conditions and
      have high endemism or other distinctive properties. Examples include coral reefs, the Arctic and its Indigenous Peoples, mountain glaciers and biodiversity hotspots. RFC2: Extreme
      weather events: risks/impacts to human health, livelihoods, assets and ecosystems from extreme weather events such as heatwaves, heavy rain, drought and associated wildfires,
      and coastal flooding. RFC3: Distribution of impacts: risks/impacts that disproportionately affect particular groups due to uneven distribution of physical climate change hazards,
      exposure or vulnerability. RFC4: Global aggregate impacts: impacts to socio-ecological systems that can be aggregated globally into a single metric, such as monetary damages, lives
      affected, species lost or ecosystem degradation at a global scale. RFC5: Large-scale singular events: relatively large, abrupt and sometimes irreversible changes in systems caused
      by global warming, such as ice sheet disintegration or thermohaline circulation slowing. Assessment methods are described in SM16.6 and are identical to AR5, but are enhanced
      by a structured approach to improve robustness and facilitate comparison between AR5 and AR6.
      Risks for (c) terrestrial and freshwater ecosystems and (d) ocean ecosystems. For c) and d), diagrams shown for each risk assume low to no adaptation. The transition to a very high
      risk level has an emphasis on irreversibility and adaptation limits.
      (e) Climate-sensitive human health outcomes under three scenarios of adaptation effectiveness. The assessed projections were based on a range of scenarios, including SRES,
      CMIP5, and ISIMIP, and, in some cases, demographic trends. The diagrams are truncated at the nearest whole ºC within the range of temperature change in 2100 under three SSP
      scenarios in panel (a).
      (f) Examples of regional key risks. Risks identified are of at least medium confidence level. Key risks are identified based on the magnitude of adverse consequences (pervasiveness
      of the consequences, degree of change, irreversibility of consequences, potential for impact thresholds or tipping points, potential for cascading effects beyond system boundaries);
      likelihood of adverse consequences; temporal characteristics of the risk; and ability to respond to the risk, e.g., by adaptation. The full set of 127 assessed global and regional key
      risks is given in SM16.7. Diagrams are provided for some risks. The development of synthetic diagrams for Small Islands, Asia and Central and South America were limited by the
      availability of adequately downscaled climate projections, with uncertainty in the direction of change, the diversity of climatologies and socioeconomic contexts across countries
      within a region, and the resulting low number of impact and risk projections for different warming levels. Absence of risks diagrams does not imply absence of risks within a region.
      (Box SPM.1) {Figure TS.4, Figure 2.11, Figure SM3.1, Figure 7.9, Figure 9.6, Figure 11.6, Figure 13.28, 16.5, 16.6, Figure 16.15, SM16.3, SM16.4, SM16.5, SM16.6 (methodologies),
      SM16.7, Figure CCP4.8, Figure CCP4.10, Figure CCP6.5, WGI AR6 2, WGI AR6 SPM A.1.2, WGI AR6 Figure SPM.8}

      Complex, Compound and Cascading Risks

      B.5         Climate change impacts and risks are becoming increasingly complex and more difficult to manage. Multiple climate
                  hazards will occur simultaneously, and multiple climatic and non-climatic risks will interact, resulting in compounding
                  overall risk and risks cascading across sectors and regions. Some responses to climate change result in new impacts and
                  risks. (high confidence) {1.3, 2.4, Box 2.2, Box 9.5, 11.5, 13.5, 14.6, Box 15.1, CCP1.2, CCP2.2, CCB COVID, CCB DISASTER,
                  CCB INTEREG, CCB SRM, }

      B.5.1       Concurrent and repeated climate hazards occur in all regions, increasing impacts and risks to health, ecosystems, infrastructure, livelihoods
                  and food (high confidence). Multiple risks interact, generating new sources of vulnerability to climate hazards, and compounding overall
                  risk (high confidence). Increasing concurrence of heat and drought events are causing crop production losses and tree mortality (high
                  confidence). Above 1.5°C global warming increasing concurrent climate extremes will increase risk of simultaneous crop losses of maize
                  in major food-producing regions, with this risk increasing further with higher global warming levels (medium confidence). Future sea
                  level rise combined with storm surge and heavy rainfall will increase compound flood risks (high confidence). Risks to health and food
                  production will be made more severe from the interaction of sudden food production losses from heat and drought, exacerbated by
                  heat-induced labour productivity losses (high confidence). These interacting impacts will increase food prices, reduce household incomes,
                  and lead to health risks of malnutrition and climate-related mortality with no or low levels of adaptation, especially in tropical regions
                  (high confidence). Risks to food safety from climate change will further compound the risks to health by increasing food contamination
                  of crops from mycotoxins and contamination of seafood from harmful algal blooms, mycotoxins, and chemical contaminants (high
                  confidence). {Figure TS.10c, 5.2, 5.4, 5.8, 5.9, 5.11, 5.12, 7.2, 7.3, 9.8, 9.11, 10.4, 11.3, 11.5, 12.3, 13.5, 14.5, 15.3, Box 15.1, 16.6, CCP1.2,
                  CCP6.2, , WGI AR6 SPM A.3.1, WGI AR6 SPM A.3.2, WGI AR6 SPM C.2.7}

      B.5.2       Adverse impacts from climate hazards and resulting risks are cascading across sectors and regions (high confidence), propagating
                  impacts along coasts and urban centres (medium confidence) and in mountain regions (high confidence). These hazards and cascading
                  risks also trigger tipping points in sensitive ecosystems and in significantly and rapidly changing social-ecological systems impacted
                  by ice melt, permafrost thaw and changing hydrology in polar regions (high confidence). Wildfires, in many regions, have affected
                  ecosystems and species, people and their built assets, economic activity, and health (medium to high confidence). In cities and

                                                                                                                                                              Summary for Policymakers

              settlements, climate impacts to key infrastructure are leading to losses and damages across water and food systems, and affect
              economic activity, with impacts extending beyond the area directly impacted by the climate hazard (high confidence). In Amazonia,
              and in some mountain regions, cascading impacts from climatic (e.g., heat) and non-climatic stressors (e.g., land use change) will result
              in irreversible and severe losses of ecosystem services and biodiversity at 2°C global warming level and beyond (medium confidence).
              Unavoidable sea level rise will bring cascading and compounding impacts resulting in losses of coastal ecosystems and ecosystem
              services, groundwater salinisation, flooding and damages to coastal infrastructure that cascade into risks to livelihoods, settlements,
              health, well-being, food and water security, and cultural values in the near to long-term (high confidence). (Figure SPM.3) {Figure TS.10,                                                SPM
              2.5, 3.4, 3.5, Box 7.3, Box 8.7, Box 9.4, 11.5, Box 11.1, 12.3, 13.9, 14.6, 15.3, 16.5, 16.6, CCP1.2, CCP2.2, CCP5.2, CCP5.3, CCP6.2,
              CCP6.3, Box CCP6.1, Box CCP6.2, CCB EXTREMES, WGI AR6 Figure SPM.8d}

B.5.3         Weather and climate extremes are causing economic and societal impacts across national boundaries through supply-chains, markets,
              and natural resource flows, with increasing transboundary risks projected across the water, energy and food sectors (high confidence).
              Supply chains that rely on specialized commodities and key infrastructure can be disrupted by weather and climate extreme events.
              Climate change causes the redistribution of marine fish stocks, increasing risk of transboundary management conflicts among fisheries
              users, and negatively affecting equitable distribution of food provisioning services as fish stocks shift from lower to higher latitude regions,
              thereby increasing the need for climate-informed transboundary management and cooperation (high confidence). Precipitation and water
              availability changes increases the risk of planned infrastructure projects, such as hydropower in some regions, having reduced productivity
              for food and energy sectors including across countries that share river basins (medium confidence). {Figure TS.10e-f, 3.4, 3.5, 4.5, 5.8, 5.13,
              6.2, 9.4, Box 9.5,14.5, Box 14.5, Box 14.6, CCP5.3, CCB DISASTER, CCB EXTREMES, CCB INTEREG, CCB MOVING PLATE}

B.5.4         Risks arise from some responses that are intended to reduce the risks of climate change, including risks from maladaptation and adverse
              side effects of some emissions reduction and carbon dioxide removal measures (high confidence). Deployment of afforestation of
              naturally unforested land, or poorly implemented bioenergy, with or without carbon capture and storage, can compound climate-related
              risks to biodiversity, water and food security, and livelihoods, especially if implemented at large scales, especially in regions with insecure
              land tenure (high confidence). {Box 2.2, 4.1, 4.7, 5.13, Table 5.18, Box 9.3, Box 13.2, CCB NATURAL, CWGB BIOECONOMY}

B.5.5         Solar radiation modification approaches, if they were to be implemented, introduce a widespread range of new risks to people and
              ecosystems, which are not well understood (high confidence). Solar radiation modification approaches have potential to offset warming
              and ameliorate some climate hazards, but substantial residual climate change or overcompensating change would occur at regional
              scales and seasonal timescales (high confidence). Large uncertainties and knowledge gaps are associated with the potential of solar
              radiation modification approaches to reduce climate change risks. Solar radiation modification would not stop atmospheric CO2
              concentrations from increasing or reduce resulting ocean acidification under continued anthropogenic emissions (high confidence).
              {CWGB SRM}

Impacts of Temporary Overshoot

B.6           If global warming transiently exceeds 1.5°C in the coming decades or later (overshoot)37, then many human and natural
              systems will face additional severe risks, compared to remaining below 1.5°C (high confidence). Depending on the mag-
              nitude and duration of overshoot, some impacts will cause release of additional greenhouse gases (medium confidence)
              and some will be irreversible, even if global warming is reduced (high confidence). (Box SPM.1, Figure SPM.3) {2.5, 3.4,
              12.3, 16.6, CCB DEEP, CCB SLR}

B.6.1         While model-based assessments of the impacts of overshoot pathways are limited, observations and current understanding of processes
              permit assessment of impacts from overshoot. Additional warming, e.g., above 1.5°C during an overshoot period this century, will
              result in irreversible impacts on certain ecosystems with low resilience, such as polar, mountain, and coastal ecosystems, impacted
              by ice-sheet, glacier melt, or by accelerating and higher committed sea level rise (high confidence).38 Risks to human systems will
              increase, including those to infrastructure, low-lying coastal settlements, some ecosystem-based adaptation measures, and associated
              livelihoods (high confidence), cultural and spiritual values (medium confidence). Projected impacts are less severe with shorter duration
              and lower levels of overshoot (medium confidence). {2.5, 3.4, 12.3, 13.2, 16.5, 16.6, CCP1.2, CCP2.2, CCP5.3, CCP6.1, CCP6.2, CCB SLR,
              WGI AR6 SPM B.5, WGI AR6 SPM C.3, SROCC 2.3, SROCC 5.4}

37    In this report, overshoot pathways exceed 1.5°C global warming and then return to that level, or below, after several decades.
38    Despite limited evidence specifically on the impacts of a temporary overshoot of 1.5°C, a much broader evidence base from process understanding and the impacts of higher global warming levels
      allows a high confidence statement on the irreversibility of some impacts that would be incurred following such an overshoot.

      Summary for Policymakers

      B.6.2         Risk of severe impacts increase with every additional increment of global warming during overshoot (high confidence). In high-carbon
                    ecosystems (currently storing 3,000 to 4,000 GtC)39 such impacts are already observed and are projected to increase with every
                    additional increment of global warming, such as increased wildfires, mass mortality of trees, drying of peatlands, and thawing of
                    permafrost, weakening natural land carbon sinks and increasing releases of greenhouse gases (medium confidence). The resulting
                    contribution to a potential amplification of global warming indicates that a return to a given global warming level or below would be
                    more challenging (medium confidence). {2.4, 2.5, CCP4.2, WGI AR6 SPM B.4.3, SROCC 5.4}

      C: Adaptation Measures and Enabling Conditions

      Adaptation, in response to current climate change, is reducing climate risks and vulnerability mostly via adjustment of existing systems. Many
      adaptation options exist and are used to help manage projected climate change impacts, but their implementation depends upon the capacity and
      effectiveness of governance and decision-making processes. These and other enabling conditions can also support climate resilient development
      (Section D).

      Current Adaptation and its Benefits

      C.1           Progress in adaptation planning and implementation has been observed across all sectors and regions, generating multiple
                    benefits (very high confidence). However, adaptation progress is unevenly distributed with observed adaptation gaps40 (high
                    confidence). Many initiatives prioritize immediate and near-term climate risk reduction which reduces the opportunity for
                    transformational adaptation (high confidence). {2.6, 5.14, 7.4, 10.4, 12.5, 13.11, 14.7, 16.3, 17.3, CCP5.2, CCP5.4}

      C.1.1         Adaptation planning and implementation have continued to increase across all regions (very high confidence). Growing public and
                    political awareness of climate impacts and risks has resulted in at least 170 countries and many cities including adaptation in their
                    climate policies and planning processes (high confidence). Decision support tools and climate services are increasingly being used
                    (very high confidence). Pilot projects and local experiments are being implemented in different sectors (high confidence). Adaptation
                    can generate multiple additional benefits such as improving agricultural productivity, innovation, health and well-being, food security,
                    livelihood, and biodiversity conservation as well as reduction of risks and damages (very high confidence). {1.4, 2.6, 3.5, 3.6, 4.7, 4.8,
                    5.4, 5.6, 5.10, 6.4, 7.4, 8.5, 9.3, 9.6, 10.4, 12.5, 13.11, 15.5, 16.3, 17.2, 17.3, 17.5, CCP5.4, CCB ADAPT, CCB NATURAL}

      C.1.2         Despite progress, adaptation gaps exist between current levels of adaptation and levels needed to respond to impacts and reduce
                    climate risks (high confidence). Most observed adaptation is fragmented, small in scale, incremental, sector-specific, designed to
                    respond to current impacts or near-term risks, and focused more on planning rather than implementation (high confidence). Observed
                    adaptation is unequally distributed across regions (high confidence), and gaps are partially driven by widening disparities between the
                    estimated costs of adaptation and documented finance allocated to adaptation (high confidence). The largest adaptation gaps exist
                    among lower income population groups (high confidence). At current rates of adaptation planning and implementation the adaptation
                    gap will continue to grow (high confidence). As adaptation options often have long implementation times, long-term planning and
                    accelerated implementation, particularly in the next decade, is important to close adaptation gaps, recognising that constraints remain
                    for some regions (high confidence). {1.1, 1.4, 5.6, 6.3, Figure 6.4, 7.4, 8.3, 10.4, 11.3, 11.7, 13.11, Box 13.1, 15.2, 15.5, 16.3, 16.5,
                    Box 16.1, Figure 16.4, Figure 16.5, 17.4, 18.2, CCP2.4, CCP5.4, CCB FINANCE, CCB SLR}

      39    At the global scale, terrestrial ecosystems currently remove more carbon from the atmosphere (-3.4 ± 0.9 Gt yr-1) than they emit (+1.6 ± 0.7 Gt yr-1), a net sink of -1.9 ± 1.1 Gt yr-1. However, recent
            climate change has shifted some systems in some regions from being net carbon sinks to net carbon sources.
      40    Adaptation gaps are defined as the difference between actually implemented adaptation and a societally set goal, determined largely by preferences related to tolerated climate change impacts and
            reflecting resource limitations and competing priorities.

                                                                                                                                                                        Summary for Policymakers

Future Adaptation Options and their Feasibility

C.2           There are feasible41 and effective42 adaptation options which can reduce risks to people and nature. The feasibility of
              implementing adaptation options in the near-term differs across sectors and regions (very high confidence). The effec-
              tiveness of adaptation to reduce climate risk is documented for specific contexts, sectors and regions (high confidence)
              and will decrease with increasing warming (high confidence). Integrated, multi-sectoral solutions that address social in-
              equities, differentiate responses based on climate risk and cut across systems, increase the feasibility and effectiveness of                                                                          SPM
              adaptation in multiple sectors (high confidence). (Figure SPM.4) {Figure TS.6e, 1.4, 3.6, 4.7, 5.12, 6.3, 7.4, 11.3, 11.7, 13.2,
              15.5, 17.6, CCP2.3, CCB FEASIB}

Land, Ocean and Ecosystems Transition

C.2.1         Adaptation to water-related risks and impacts make up the majority of all documented adaptation (high confidence). For inland
              flooding, combinations of non-structural measures like early warning systems and structural measures like levees have reduced loss
              of lives (medium confidence). Enhancing natural water retention such as by restoring wetlands and rivers, land use planning such
              as no build zones or upstream forest management, can further reduce flood risk (medium confidence). On-farm water management,
              water storage, soil moisture conservation and irrigation are some of the most common adaptation responses and provide economic,
              institutional or ecological benefits and reduce vulnerability (high confidence). Irrigation is effective in reducing drought risk and climate
              impacts in many regions and has several livelihood benefits, but needs appropriate management to avoid potential adverse outcomes,
              which can include accelerated depletion of groundwater and other water sources and increased soil salinization (medium confidence).
              Large scale irrigation can also alter local to regional temperature and precipitation patterns (high confidence), including both alleviating
              and exacerbating temperature extremes (medium confidence). The effectiveness of most water-related adaptation options to reduce
              projected risks declines with increasing warming (high confidence). {4.1, 4.6, 4.7, Box 4.3, Box 4.6, Box 4.7, Figure 4.22, Figure 4.28,
              Figure 4.29, Table 4.9, 9.3, 9.7, 11.3, 12.5, 13.1, 13.2, 16.3, CCP5.4}

C.2.2         Effective adaptation options, together with supportive public policies enhance food availability and stability and reduce climate risk for
              food systems while increasing their sustainability (medium confidence). Effective options include cultivar improvements, agroforestry,
              community-based adaptation, farm and landscape diversification, and urban agriculture (high confidence). Institutional feasibility,
              adaptation limits of crops and cost effectiveness also influence the effectiveness of the adaptation options (limited evidence, medium
              agreement). Agroecological principles and practices, ecosystem-based management in fisheries and aquaculture, and other approaches
              that work with natural processes support food security, nutrition, health and well-being, livelihoods and biodiversity, sustainability and
              ecosystem services (high confidence). These services include pest control, pollination, buffering of temperature extremes, and carbon
              sequestration and storage (high confidence). Trade-offs and barriers associated with such approaches include costs of establishment,
              access to inputs and viable markets, new knowledge and management (high confidence) and their potential effectiveness varies by
              socioeconomic context, ecosystem zone, species combinations and institutional support (medium confidence). Integrated, multi-sectoral
              solutions that address social inequities and differentiate responses based on climate risk and local situation will enhance food security
              and nutrition (high confidence). Adaptation strategies which reduce food loss and waste or support balanced diets33 (as described in the
              IPCC Special Report on Climate Change and Land) contribute to nutrition, health, biodiversity and other environmental benefits (high
              confidence). {3.2, 4.7, 4.6, Box 4.3, 5.4, 5.5, 5.6, 5.8, 5.9, 5.10, 5.11, 5.12, 5.13, 5.14, Box 5.10, Box 5.13, 6.3, 7.4, 10.4, 12.5, 13.5, 13.10,

C.2.3         Adaptation for natural forests43 includes conservation, protection and restoration measures. In managed forests43, adaptation options
              include sustainable forest management, diversifying and adjusting tree species compositions to build resilience, and managing
              increased risks from pests and diseases and wildfires. Restoring natural forests and drained peatlands and improving sustainability
              of managed forests, generally enhances the resilience of carbon stocks and sinks. Cooperation, and inclusive decision making, with
              local communities and Indigenous Peoples, as well as recognition of inherent rights of Indigenous Peoples, is integral to successful
              forest adaptation in many areas. (high confidence) {2.6, Box 2.2, 5.6, 5.13, Table 5.23, 11.4, 12.5, 13.5, Box 14.1, Box 14.2, CCP7.5,

41    In this report, feasibility refers to the potential for a mitigation or adaptation option to be implemented. Factors influencing feasibility are context-dependent, temporally dynamic, and may vary between
      different groups and actors. Feasibility depends on geophysical, environmental-ecological, technological, economic, socio-cultural and institutional factors that enable or constrain the implementation
      of an option. The feasibility of options may change when different options are combined and increase when enabling conditions are strengthened.
42    Effectiveness refers to the extent to which an adaptation option is anticipated or observed to reduce climate-related risk.
43    In this report, the term natural forests describes those which are subject to little or no direct human intervention, whereas the term managed forests describes those where planting or other
      management activities take place, including those managed for commodity production.


     (a) Diverse feasible climate responses and adaptation options exist to respond to Representative Key Risks of climate change, with varying synergies with mitigation
     Multidimensional feasibility and synergies with mitigation of climate responses and adaptation options relevant in the near-term, at global scale and up to 1.5°C of global warming
                                                                                                                                                Dimensions of potential feasibility

            System       Representative                                 Climate responses1              Potential        with             Techno- Insti-                         Environ- Geo-                   Feasibility level and
        transitions      key risks                                  and adaptation options             feasibility    mitigation Economic logical tutional             Social     mental physical                synergies with mitigation
                                                                                                                                                                                                                                                              Summary for Policymakers

                                                                Coastal defence and hardening                         not assessed
                         Coastal socio-
                         ecological systems               Integrated coastal zone management                                                                                                                          Medium
                                                                      Forest-based adaptation2
                                                                                                                                                                                                                 /    Insufficient evidence
        Land and         Terrestrial and                  Sustainable aquaculture and fisheries
            ocean        ocean ecosystem
       ecosystems        services                                           Agroforestry
                                                                                                                                                                                                                      Dimensions of
                                       Biodiversity management and ecosystem connectivity
                                                                                                                                                                                                                      potential feasibility
                         security       Water use efficiency and water resource management
                                                                                                                                                                                                                 Confidence level
                         Food                                  Improved cropland management                                                                                                                      in potential feasibility and
                         security                                     Efficient livestock systems                                                                                                                in synergies with mitigation
         Urban and       Critical                   Green infrastructure and ecosystem services
     infrastructure      infrastructure,                                                                                                                                                                              Medium
           systems                                    Sustainable land use and urban planning
                         networks                                                                                                                                                                                     Low
                         and services                    Sustainable urban water management

                         Water security                            Improve water use efficiency                                                                           /
            Energy                                                                                                                                                                                               Footnotes:
                         Critical infrastructure,                       Resilient power systems                                                                                           not applicable
           systems                                                                                                                                                                                           1
                         networks and services                                                                                                                                            not applicable
                                                                                                                                                                                                                 The term response is used
                                                                                Energy reliability
                                                                                                                                                                                                                 here instead of adaptation
                         Human health                                                                                                                                                                            because some responses,
                                                         Health and health systems adaptation                                                                                                   /                such as retreat, may or may
                                                                                                                                                                                                                 not be considered to be
                         Living standards and equity                   Livelihood diversification                                                                                                                adaptation.
                         Peace and                                                                                                                                                                               Including sustainable forest
             Cross-                                        Planned relocation and resettlement
           sectoral      human mobility                                                                                                                                                                          management, forest
                                                                            Human migration3                                                                                                                     conservation and restoration,
                                                                                                                                                                                                                 reforestation and
                         Other                                        Disaster risk management                                                                                                                   afforestation.
                         cross-cutting      Climate services, including Early Warning Systems                               /                                                                                3
                         risks                                                                                                                                                                                   Migration, when voluntary,
                                                                                Social safety nets                                                                                                               safe and orderly, allows
                                                                                                                                                                                                                 reduction of risks to climatic
                                                                     Risk spreading and sharing                                                                                                                  and non-climatic stressors.

     Figure SPM.4 | (a) Climate responses and adaptation options, organized by System Transitions and Representative Key Risks (RKRs), are assessed for their multidimensional feasibility at global scale, in the
     near term and up to 1.5°C global warming. As literature above 1.5°C is limited, feasibility at higher levels of warming may change, which is currently not possible to assess robustly. Climate responses and adaptation options at global
     scale are drawn from a set of options assessed in AR6 that have robust evidence across the feasibility dimensions. This figure shows the six feasibility dimensions (economic, technological, institutional, social, environmental and geophysical)
     that are used to calculate the potential feasibility of climate responses and adaptation options, along with their synergies with mitigation. For potential feasibility and feasibility dimensions, the figure shows high, medium, or low feasibility.
     Synergies with mitigation are identified as high, medium, and low. Insufficient evidence is denoted by a dash. {CCB FEASIB, Table SMCCB FEASIB.1.1, SR1.5 4.SM.4.3}
     (b) Climate responses and adaptation options have benefits for ecosystems, ethnic groups, gender equity, low-income groups and the Sustainable Development Goals
     Relations of sectors and groups at risk (as observed) and the SDGs (relevant in the near-term, at global scale and up to 1.5°C of global warming) with climate responses and adaptation options
                                                                                             Observed relation with                                 Relation with
                                                                                            sectors and groups at risk                    Sustainable Development Goals4, 5

            System                                     Climate responses¹           Ecosystems    Ethnic    Gender    Low-
        transitions                                and adaptation options            and their    groups    equity   income       1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17                      Types of relation
                                                                                      services                       groups
                                                                                                    /                                     +                + – •             • •                 +    With benefits
                                                Coastal defence and hardening           –                      –         –
                                          Integrated coastal zone management            •           /          •         /        +       + + +          +     +             + + + +             –    With dis-benefits
                                                                                                                                                                                                 •    Not clear or mixed
                                                      Forest-based adaptation2                      not assessed                  + • +        + + + + + + +          +        +
                                                                                                                                                                                                 /    Insufficient evidence
        Land and                          Sustainable aquaculture and fisheries         +           +          +         +        + + +        + +   + + + +          +      + +
       ecosystems                                                   Agroforestry                    not assessed                  + + +        + + + +   + +          +        +        +
                       Biodiversity management and ecosystem connectivity               +           /          /         –            +          +         +          +        +                 Confidence level
                                                                                                                                                                                                 in type of relation with
                                                                                                                                                                                                 sectors and groups at risk
                       Water use efficiency and water resource management               +           •          •         •                +    • + •            • + +           + •
                                               Improved cropland management             +           +          +         +        + + +        + + + + + •            +         + + +                 Medium
                                                     Efficient livestock systems                    not assessed                  + + +        •     + +              +         +                     Low

         Urban and                   Green infrastructure and ecosystem services        +           /          +         +                +       +      + + + + +
     infrastructure                                                                                                                                                                                   Related
           systems                     Sustainable land use and urban planning          +           •          •         •                +       +      + + + +                                      Sustainable Development Goals
                                         Sustainable urban water management                         not assessed                          +       +      + + + +                                1: No Poverty
                                                                                                                                                                                                2: Zero Hunger
                                                   Improve water use efficiency         +           /          •         •        + + + + + + +                +                +
                                                                                                                                                                                                3: Good Health and Well-being
           Energy                                      Resilient power systems                      not assessed                                                                                4: Quality Education
          systems                                                                                                                 + + + + + + +                +
                                                               Energy reliability                   not assessed                  + + + + + + +                +                                5: Gender Equality
                                                                                                                                                                                                6: Clean Water and Sanitation
                                         Health and health systems adaptation           •           •          +         +        + + + + + + + +              + + +         + + + +            7: Affordable and Clean Energy
                                                                                                                                                                                                8: Decent Work and Economic Growth
                                                       Livelihood diversification       +           /          •         •        + + + + • • • • • – – •                       •               9: Industry, Innovation and Infrastructure
                                                                                                    •          •         •                                                          •          10: Reducing Inequality
            Cross-                         Planned relocation and resettlement          +
          sectoral                                                                                                                                                                             11: Sustainable Cities and Communities
                                                            Human migration3            +           •          •         •        • • • + •              +      • •                 •
                                                                                                                                                                                               12: Responsible Consumption and Production
                                                     Disaster risk management                       not assessed                  +   +   + + • +            • + +                +            13: Climate Action
                                                                                                                                                                                               14: Life Below Water
                           Climate services, including Early Warning Systems            +           /          –         +        +   +   +   •              • • +              + + +
                                                                                                                                                                                               15: Life On Land
                                                              Social safety nets        •           +          +         +        +   +   + +            +     + +
                                                                                                                                                                                               16: Peace, Justice, and Strong Institutions
                                                    Risk spreading and sharing          –           –          •         •        +   +   +              • +          •         •              17: Partnerships for the Goals
                      Footnotes: The term response is used here instead of adaptation because some responses, such as retreat, may or may not be considered to be adaptation. 2 Including sustainable forest management, forest
                      conservation and restoration, reforestation and afforestation. 3 Migration, when voluntary, safe and orderly, allows reduction of risks to climatic and non-climatic stressors. 4 The Sustainable Development Goals
                      (SDGs) are integrated and indivisible, and efforts to achieve any goal in isolation may trigger synergies or trade-offs with other SDGs. 5 Relevant in the near-term, at global scale and up to 1.5°C of global warming.

                                                                                                                                                                                                                                                 Summary for Policymakers

      Summary for Policymakers

      Figure SPM.4 | (b) Climate responses and adaptation options, organized by System Transitions and Representative Key Risks, are assessed at global scale
      for their likely ability to reduce risks for ecosystems and social groups at risk, as well as their relation with the 17 Sustainable Development Goals (SDGs).
      Climate responses and adaptation options are assessed for observed benefits (+) to ecosystems and their services, ethnic groups, gender equity, and low-income groups, or observed
      dis-benefits (-) for these systems and groups. Where there is highly diverging evidence of benefits/ dis-benefits across the scientific literature, e.g., based on differences between
      regions, it is shown as not clear or mixed (•). Insufficient evidence is shown by a dash. The relation with the SDGs is assessed as having benefits (+), dis-benefits (-) or not clear or
      mixed (•) based on the impacts of the climate response and adaptation option on each SDG. Areas not coloured indicate there is no evidence of a relation or no interaction with the
      respective SDG. The climate responses and adaptation options are drawn from two assessments. For comparability of climate responses and adaptation options see Table SM17.5.
      {17.2, 17.5, CCB FEASIB}

      C.2.4        Conservation, protection and restoration of terrestrial, freshwater, coastal and ocean ecosystems, together with targeted management
                   to adapt to unavoidable impacts of climate change, reduces the vulnerability of biodiversity to climate change (high confidence). The
                   resilience of species, biological communities and ecosystem processes increases with size of natural area, by restoration of degraded
                   areas and by reducing non-climatic stressors (high confidence). To be effective, conservation and restoration actions will increasingly
                   need to be responsive, as appropriate, to ongoing changes at various scales, and plan for future changes in ecosystem structure,
                   community composition and species’ distributions, especially as 1.5°C global warming is approached and even more so if it is exceeded
                   (high confidence). Adaptation options, where circumstances allow, include facilitating the movement of species to new ecologically
                   appropriate locations, particularly through increasing connectivity between conserved or protected areas, targeted intensive
                   management for vulnerable species and protecting refugial areas where species can survive locally (medium confidence). {2.3, 2,6,
                   Figure 2.1, Table 2.6, 3.3, 3.6, Box 3.4, 4.6, Box 4.6, Box 11.2, 12.3, 12.5, 13.4, 14.7, CCP5.4, CCB FEASIB}

      C.2.5        Effective Ecosystem-based Adaptation44 reduces a range of climate change risks to people, biodiversity and ecosystem services with
                   multiple co-benefits (high confidence). Ecosystem-based Adaptation is vulnerable to climate change impacts, with effectiveness
                   declining with increasing global warming (high confidence). Urban greening using trees and other vegetation can provide local cooling
                   (very high confidence). Natural river systems, wetlands and upstream forest ecosystems reduce flood risk by storing water and slowing
                   water flow, in most circumstances (high confidence). Coastal wetlands protect against coastal erosion and flooding associated with
                   storms and sea level rise where sufficient space and adequate habitats are available until rates of sea level rise exceeds natural
                   adaptive capacity to build sediment (very high confidence). {2.4, 2.5, 2.6, Table 2.7, 3.4, 3.5, 3.6, Figure 3.26, 4.6, Box 4.6, Box 4.7, 5.5,
                   5.14, Box 5.11, 6.3, 6.4, Figure 6.6, 7.4, 8.5, 8.6, 9.6, 9.8, 9.9, 10.2, 11.3, 12.5, 13.3, 13.4, 13.5, 14.5, Box 14.7, 16.3, 18.3, CCP5.4, CCB

      Urban, Rural and Infrastructure Transition

      C.2.6        Considering climate change impacts and risks in the design and planning of urban and rural settlements and infrastructure is critical
                   for resilience and enhancing human well-being (high confidence). The urgent provision of basic services, infrastructure, livelihood
                   diversification and employment, strengthening of local and regional food systems and community-based adaptation enhance lives and
                   livelihoods, particularly of low-income and marginalised groups (high confidence). Inclusive, integrated and long-term planning at local,
                   municipal, sub-national and national scales, together with effective regulation and monitoring systems and financial and technological
                   resources and capabilities foster urban and rural system transition (high confidence). Effective partnerships between governments, civil
                   society, and private sector organizations, across scales provide infrastructure and services in ways that enhance the adaptive capacity
                   of vulnerable people (medium to high confidence). {5.12, 5.13, 5.14, 6.3, 6.4, Box 6.3, Box 6.6, Table 6.6, 7.4, 12.5, 13.6, 14.5, Box 14.4,
                   Box 17.4, CCP2.3, CCP2.4, CCP5.4, CCB FEASIB}

      C.2.7        An increasing number of adaptation responses exist for urban systems, but their feasibility and effectiveness is constrained by
                   institutional, financial, and technological access and capacity, and depends on coordinated and contextually appropriate responses
                   across physical, natural and social infrastructure (high confidence). Globally, more financing is directed at physical infrastructure than
                   natural and social infrastructure (medium confidence) and there is limited evidence of investment in the informal settlements hosting
                   the most vulnerable urban residents (medium to high confidence). Ecosystem-based adaptation (e.g., urban agriculture and forestry,
                   river restoration) has increasingly been applied in urban areas (high confidence). Combined ecosystem-based and structural adaptation
                   responses are being developed, and there is growing evidence of their potential to reduce adaptation costs and contribute to flood
                   control, sanitation, water resources management, landslide prevention and coastal protection (medium confidence). {3.6, Box 4.6, 5.12,
                   6.3, 6.4, Table 6.8, 7.4, 9.7, 9.9, 10.4, Table 10.3, 11.3, 11.7, Box 11.6, 12.5, 13.2, 13.3, 13.6, 14.5, 15.5, 17.2, Box 17.4, CCP2.3, CCP
                   3.2, CCP5.4, CCB FEASIB, CCB SLR, SROCC SPM}

      44   Ecosystem based Adaptation (EbA) is recognised internationally under the Convention on Biological Diversity (CBD14/5). A related concept is Nature-based Solutions (NbS), which includes a broader
           range of approaches with safeguards, including those that contribute to adaptation and mitigation. The term ‘Nature-based Solutions’ is widely but not universally used in the scientific literature. The
           term is the subject of ongoing debate, with concerns that it may lead to the misunderstanding that NbS on its own can provide a global solution to climate change.

                                                                                                                                                      Summary for Policymakers

C.2.8        Sea level rise poses a distinctive and severe adaptation challenge as it implies dealing with slow onset changes and increased frequency
             and magnitude of extreme sea level events which will escalate in the coming decades (high confidence). Such adaptation challenges
             would occur much earlier under high rates of sea level rise, in particular if low-likelihood, high impact outcomes associated with
             collapsing ice sheets occur (high confidence). Responses to ongoing sea level rise and land subsidence in low-lying coastal cities and
             settlements and small islands include protection, accommodation, advance and planned relocation (high confidence)45. These responses
             are more effective if combined and/or sequenced, planned well ahead, aligned with sociocultural values and development priorities,
             and underpinned by inclusive community engagement processes (high confidence). { 6.2, 10.4, 11.7, Box 11.6, 13.2, 14.5, 15.5, CCP2.3,                               SPM
             CCB SLR, WGI AR6 SPM B.5, WGI AR6 SPM C.3, SROCC SPM C3.2}

C.2.9        Approximately 3.4 billion people globally live in rural areas around the world, and many are highly vulnerable to climate change.
             Integrating climate adaptation into social protection programs, including cash transfers and public works programmes, is highly feasible
             and increases resilience to climate change, especially when supported by basic services and infrastructure. Social safety nets are
             increasingly being reconfigured to build adaptive capacities of the most vulnerable in rural and also urban communities. Social safety
             nets that support climate change adaptation have strong co-benefits with development goals such as education, poverty alleviation,
             gender inclusion and food security. (high confidence) {5.14, 9.4, 9.10, 9.11, 12.5, 14.5, CCP5.4, CCB FEASIB, CCB GENDER}

Energy System Transition

C.2.10       Within energy system transitions, the most feasible adaptation options support infrastructure resilience, reliable power systems
             and efficient water use for existing and new energy generation systems (very high confidence). Energy generation diversification,
             including with renewable energy resources and generation that can be decentralised depending on context (e.g., wind, solar, small
             scale hydroelectric) and demand side management (e.g., storage, and energy efficiency improvements) can reduce vulnerabilities to
             climate change, especially in rural populations (high confidence). Adaptations for hydropower and thermo-electric power generation
             are effective in most regions up to 1.5°C to 2°C, with decreasing effectiveness at higher levels of warming (medium confidence).
             Climate responsive energy markets, updated design standards on energy assets according to current and projected climate change,
             smart-grid technologies, robust transmission systems and improved capacity to respond to supply deficits have high feasibility in the
             medium- to long-term, with mitigation co-benefits (very high confidence). {4.6, 4.7, Figure 4.28, Figure 4.29, 10.4, Table 11.8, 13.6,
             Figure 13.16, Figure 13.19, 18.3,CCP5.2, CCP5.4, CCB FEASIB, CWGB BIOECONOMY}

Cross-cutting Options

C.2.11       Strengthening the climate resiliency of health systems will protect and promote human health and well-being (high confidence). There
             are multiple opportunities for targeted investments and finance to protect against exposure to climate hazards, particularly for those
             at highest risk. Heat Health Action Plans that include early warning and response systems are effective adaptation options for extreme
             heat (high confidence). Effective adaptation options for water-borne and food-borne diseases include improving access to potable
             water, reducing exposure of water and sanitation systems to flooding and extreme weather events, and improved early warning systems
             (very high confidence). For vector-borne diseases, effective adaptation options include surveillance, early warning systems, and vaccine
             development (very high confidence). Effective adaptation options for reducing mental health risks under climate change include improving
             surveillance, access to mental health care, and monitoring of psychosocial impacts from extreme weather events (high confidence). Health
             and well-being would benefit from integrated adaptation approaches that mainstream health into food, livelihoods, social protection,
             infrastructure, water and sanitation policies requiring collaboration and coordination at all scales of governance (very high confidence).
             {5.12, 6.3, 7.4, 9.10, Box 9.7, 11.3, 12.5, 13.7, 14.5, CCB COVID, CCB FEASIB, CCB ILLNESS }

C.2.12       Increasing adaptive capacities minimises the negative impacts of climate-related displacement and involuntary migration for migrants
             and sending and receiving areas (high confidence). This improves the degree of choice under which migration decisions are made,
             ensuring safe and orderly movements of people within and between countries (high confidence). Some development reduces underlying
             vulnerabilities associated with conflict, and adaptation contributes by reducing the impacts of climate change on climate sensitive
             drivers of conflict (high confidence). Risks to peace are reduced, for example, by supporting people in climate-sensitive economic
             activities (medium confidence) and advancing women’s empowerment (high confidence). {7.4, Box 9.8, Box 10.2, 12.5, CCB FEASIB,
             CCB MIGRATE}

45   The term ‘response’ is used here instead of adaptation because some responses, such as retreat, may or may not be considered to be adaptation.

      Summary for Policymakers

      C.2.13        There are a range of adaptation options, such as disaster risk management, early warning systems, climate services and risk spreading
                    and sharing that have broad applicability across sectors and provide greater benefits to other adaptation options when combined (high
                    confidence). For example, climate services that are inclusive of different users and providers can improve agricultural practices, inform
                    better water use and efficiency, and enable resilient infrastructure planning (high confidence). {2.6, 3.6, 4.7, 5.4, 5.5, 5.6, 5.8, 5.9, 5.12,
                    5.14, 9.4, 9.8, 10.4, 12.5, 13.11, CCP5.4, CCB FEASIB, CCB MOVING PLATE}

      Limits to Adaptation

      C.3           Soft limits to some human adaptation have been reached, but can be overcome by addressing a range of constraints,
                    primarily financial, governance, institutional and policy constraints (high confidence). Hard limits to adaptation have been
                    reached in some ecosystems (high confidence). With increasing global warming, losses and damages will increase and
                    additional human and natural systems will reach adaptation limits (high confidence). {Figure TS.7, 1.4, 2.4, 2.5, 2.6, 3.4, 3.6,
                    4.7, Figure 4.30, 5.5, Table 8.6, Box 10.7, 11.7, Table 11.16, 12.5, 13.2, 13.5, 13.6, 13.10, 13.11, Figure 13.21, 14.5, 15.6, 16.4,
                    Figure 16.8, Table 16.3, Table 16.4, CCP1.2, CCP1.3, CCP2.3, CCP3.3, CCP5.2, CCP5.4, CCP6.3, CCP7.3, CCB SLR}

      C.3.1         Soft limits to some human adaptation have been reached, but can be overcome by addressing a range of constraints, which primarily
                    consist of financial, governance, institutional and policy constraints (high confidence). For example, individuals and households in
                    low-lying coastal areas in Australasia and Small Islands and smallholder farmers in Central and South America, Africa, Europe and Asia
                    have reached soft limits (medium confidence). Inequity and poverty also constrain adaptation, leading to soft limits and resulting in
                    disproportionate exposure and impacts for most vulnerable groups (high confidence). Lack of climate literacy46 at all levels and limited
                    availability of information and data pose further constraints to adaptation planning and implementation (medium confidence). {1.4, 4.7,
                    5.4, 8.4, Table 8.6, 9.1, 9.4, 9.5, 9.8, 11.7, 12.5 13.5, 15.3, 15.5, 15.6, 16.4, Box 16.1, Figure 16.8, CCP5.2, CCP5.4, CCP6.3}

      C.3.2         Financial constraints are important determinants of soft limits to adaptation across sectors and all regions (high confidence). Although
                    global tracked climate finance has shown an upward trend since AR5, current global financial flows for adaptation, including from
                    public and private finance sources, are insufficient for and constrain implementation of adaptation options especially in developing
                    countries (high confidence). The overwhelming majority of global tracked climate finance was targeted to mitigation while a small
                    proportion was targeted to adaptation (very high confidence). Adaptation finance has come predominantly from public sources (very
                    high confidence). Adverse climate impacts can reduce the availability of financial resources by incurring losses and damages and
                    through impeding national economic growth, thereby further increasing financial constraints for adaptation, particularly for developing
                    and least developed countries (medium confidence). {Figure TS.7, 1.4, 2.6, 3.6, 4.7, Figure 4.30, 5.14, 7.4, 8.4, Table 8.6, 9.4, 9.9, 9.11,
                    10.5, 12.5, 13.3, 13.11, Box 14.4, 15.6, 16.2, 16.4, Figure 16.8, Table 16.4, 17.4, 18.1, CCP2.4, CCP5.4, CCP6.3, CCB FINANCE}

      C.3.3         Many natural systems are near the hard limits of their natural adaptation capacity and additional systems will reach limits with
                    increasing global warming (high confidence). Ecosystems already reaching or surpassing hard adaptation limits include some warm-­
                    water coral reefs, some coastal wetlands, some rainforests, and some polar and mountain ecosystems (high confidence). Above 1.5°C
                    global warming level, some Ecosystem-based Adaptation measures will lose their effectiveness in providing benefits to people as these
                    ecosystems will reach hard adaptation limits (high confidence). (Figure SPM.4) {1.4, 2.4, 2.6, 3.4, 3.6, 9.6, Box 11.2, 13.4, 14.5, 15.5,
                    16.4, 16.6, 17.2, CCP1.2, CCP5.2, CCP6.3, CCP7.3, CCB SLR}

      C.3.4         In human systems, some coastal settlements face soft adaptation limits due to technical and financial difficulties of implementing
                    coastal protection (high confidence). Above 1.5°C global warming level, limited freshwater resources pose potential hard limits for
                    Small Islands and for regions dependent on glacier and snow-melt (medium confidence). By 2°C global warming level, soft limits are
                    projected for multiple staple crops in many growing areas, particularly in tropical regions (high confidence). By 3°C global warming
                    level, soft limits are projected for some water management measures for many regions, with hard limits projected for parts of Europe
                    (medium confidence). Transitioning from incremental to transformational adaptation can help overcome soft adaptation limits (high
                    confidence). {1.4, 4.7, 5.4, 5.8, 7.2, 7.3, 8.4, Table 8.6, 9.8, 10.4, 12.5, 13.2, 13.6, 16.4, 17.2, CCP1.3. Box CCP1.1, CCP2.3, CCP3.3,
                    CCP4.4, CCP5.3, CCB SLR}

      C.3.5         Adaptation does not prevent all losses and damages, even with effective adaptation and before reaching soft and hard limits. Losses
                    and damages are unequally distributed across systems, regions and sectors and are not comprehensively addressed by current financial,
                    governance and institutional arrangements, particularly in vulnerable developing countries. With increasing global warming, losses and
                    damages increase and become increasingly difficult to avoid, while strongly concentrated among the poorest vulnerable populations.
                    (high confidence) {1.4, 2.6, 3.4, 3.6, 6.3, Figure 6.4, 8.4, 13.2, 13.7, 13.10, 17.2, CCP2.3, CCP4.4, CCB LOSS, CCB SLR, CWGB ECONOMIC}

      46    Climate literacy encompasses being aware of climate change, its anthropogenic causes and implications.

                                                                                                                                                           Summary for Policymakers

Avoiding Maladaptation
C.4          There is increased evidence of maladaptation15 across many sectors and regions since the AR5. Maladaptive responses
             to climate change can create lock-ins of vulnerability, exposure and risks that are difficult and expensive to change and
             exacerbate existing inequalities. Maladaptation can be avoided by flexible, multi-sectoral, inclusive and long-term plan-
             ning and implementation of adaptation actions with benefits to many sectors and systems. (high confidence) {1.3, 1.4,
             2.6, Box 2.2, 3.2, 3.6, 4.6, 4.7, Box 4.3, Box 4.5, Figure 4.29, 5.6, 5.13, 8.2, 8.3, 8.4, 8.6, 9.6, 9.7, 9.8, 9.9, 9.10, 9.11, Box 9.5,
             Box 9.8, Box 9.9, Box 11.6, 13.11, 13.3, 13.4, 13.5, 14.5, 15.5, 15.6, 16.3, 17.2, 17.3, 17.4, 17.5, 17.6, CCP2.3, CCP2.3,                                                              SPM

C.4.1        Actions that focus on sectors and risks in isolation and on short-term gains often lead to maladaptation if long-term impacts of
             the adaptation option and long-term adaptation commitment are not taken into account (high confidence). The implementation of
             these maladaptive actions can result in infrastructure and institutions that are inflexible and/or expensive to change (high confidence).
             For example, seawalls effectively reduce impacts to people and assets in the short-term but can also result in lock-ins and increase
             exposure to climate risks in the long-term unless they are integrated into a long-term adaptive plan (high confidence). Adaptation
             integrated with development reduces lock-ins and creates opportunities (e.g., infrastructure upgrading) (medium confidence). {1.4, 3.4,
             3.6, 10.4, 11.7, Box 11.6, 13.2, 17.2, 17.5, 17.6, CCP 2.3, CCB DEEP, CCB SLR}

C.4.2        Biodiversity and ecosystem resilience to climate change are decreased by maladaptive actions, which also constrain ecosystem
             services. Examples of these maladaptive actions for ecosystems include fire suppression in naturally fire-adapted ecosystems or hard
             defences against flooding. These actions reduce space for natural processes and represent a severe form of maladaptation for the
             ecosystems they degrade, replace or fragment, thereby reducing their resilience to climate change and the ability to provide ecosystem
             services for adaptation. Considering biodiversity and autonomous adaptation in long-term planning processes reduces the risk of
             maladaptation. (high confidence) {2.4, 2.6, Table 2.7, 3.4, 3.6, 4.7, 5.6, 5.13, Table 5.21, Table 5.23, Box 11.2, 13.2, Box 13.2, 17.2, 17.5,

C.4.3        Maladaptation especially affects marginalised and vulnerable groups adversely (e.g., Indigenous Peoples, ethnic minorities, low-income
             households, informal settlements), reinforcing and entrenching existing inequities. Adaptation planning and implementation that do not
             consider adverse outcomes for different groups can lead to maladaptation, increasing exposure to risks, marginalising people from certain
             socioeconomic or livelihood groups, and exacerbating inequity. Inclusive planning initiatives informed by cultural values, Indigenous
             knowledge, local knowledge, and scientific knowledge can help prevent maladaptation. (high confidence) (Figure SPM.4) {2.6, 3.6, 4.3,
             4.6, 4.8, 5.12, 5.13, 5.14, 6.1, Box 7.1, 8.4, 11.4, 12.5, Box 13.2, 14.4, Box 14.1, 17.2, 17.5, 18.2, 17.2, CCP2.4}

C.4.4        To minimize maladaptation, multi-sectoral, multi-actor and inclusive planning with flexible pathways encourages low-regret47 and
             timely actions that keep options open, ensure benefits in multiple sectors and systems and indicate the available solution space for
             adapting to long-term climate change (very high confidence). Maladaptation is also minimized by planning that accounts for the time it
             takes to adapt (high confidence), the uncertainty about the rate and magnitude of climate risk (medium confidence) and a wide range
             of potentially adverse consequences of adaptation actions (high confidence). {1.4, 3.6, 5.12, 5.13, 5.14, 11.6, 11.7, 17.3, 17.6, CCP2.3,
             CCP2.4, CCP5.4, CCB DEEP, CCB SLR}

Enabling Conditions
C.5          Enabling conditions are key for implementing, accelerating and sustaining adaptation in human systems and ecosystems.
             These include political commitment and follow-through, institutional frameworks, policies and instruments with clear
             goals and priorities, enhanced knowledge on impacts and solutions, mobilization of and access to adequate financial re-
             sources, monitoring and evaluation, and inclusive governance processes. (high confidence) {1.4, 2.6, 3.6, 4.8, 6.4, 7.4, 8.5,
             9.4, 10.5, 11.4, 11.7, 12.5, 13.11, 14.7, 15.6, 17.4, 18.4, CCP2.4, CCP5.4, CCB FINANCE, CCB INDIG}

C.5.1        Political commitment and follow-through across all levels of government accelerate the implementation of adaptation actions
             (high confidence). Implementing actions can require large upfront investments of human, financial and technological resources
             (high confidence), whilst some benefits could only become visible in the next decade or beyond (medium confidence). Accelerating
             commitment and follow-through is promoted by rising public awareness, building business cases for adaptation, accountability and
             transparency mechanisms, monitoring and evaluation of adaptation progress, social movements, and climate-related litigation in some
             regions (medium confidence). {3.6, 4.8, 5.8, 6.4, 8.5, 9.4, 11.7, 12.5, 13.11, 17.4, 17.5, 18.4, CCP2.4, CCB COVID}

47    From AR5, an option that would generate net social and/or economic benefits under current climate change and a range of future climate change scenarios, and represent one example of robust

      Summary for Policymakers

      C.5.2    Institutional frameworks, policies and instruments that set clear adaptation goals and define responsibilities and commitments and that
               are coordinated amongst actors and governance levels, strengthen and sustain adaptation actions (very high confidence). Sustained
               adaptation actions are strengthened by mainstreaming adaptation into institutional budget and policy planning cycles, statutory
               planning, monitoring and evaluation frameworks and into recovery efforts from disaster events (high confidence). Instruments that
               incorporate adaptation such as policy and legal frameworks, behavioural incentives, and economic instruments that address market
               failures, such as climate risk disclosure, inclusive and deliberative processes strengthen adaptation actions by public and private actors
SPM            (medium confidence). {1.4, 3.6, 4.8, 5.14, 6.3, 6.4, 7.4, 9.4, 10.4, 11.7, Box 11.6, Table 11.17, 13.10, 13.11, 14.7, 15.6, 17.3, 17.4, 17.5,
               17.6, 18.4, CCP2.4, CCP5.4, CCP6.3, CCB DEEP}

      C.5.3    Enhancing knowledge on risks, impacts, and their consequences, and available adaptation options promotes societal and policy
               responses (high confidence). A wide range of top-down, bottom-up and co-produced processes and sources can deepen climate
               knowledge and sharing, including capacity building at all scales, educational and information programmes, using the arts, participatory
               modelling and climate services, Indigenous knowledge and local knowledge and citizen science (high confidence). These measures can
               facilitate awareness, heighten risk perception and influence behaviours (high confidence). {1.3, 3.6, 4.8, 5.9, 5.14, 6.4, Table 6.8, 7.4,
               9.4, 10.5, 11.1, 11.7, 12.5, 13.9, 13.11, 14.3, 15.6, 15.6, 17.4, 18.4, CCP2.4.1, CCB INDIG}

      C.5.4    With adaptation finance needs estimated to be higher than those presented in AR5, enhanced mobilization of and access to financial
               resources are essential for implementation of adaptation and to reduce adaptation gaps (high confidence). Building capacity and
               removing some barriers to accessing finance is fundamental to accelerate adaptation, especially for vulnerable groups, regions and
               sectors (high confidence). Public and private finance instruments include inter alia grants, guarantee, equity, concessional debt,
               market debt, and internal budget allocation as well as savings in households and insurance. Public finance is an important enabler
               of adaptation (high confidence). Public mechanisms and finance can leverage private sector finance for adaptation by addressing
               real and perceived regulatory, cost and market barriers, for example via public-private partnerships (high confidence). Financial and
               technological resources enable effective and ongoing implementation of adaptation, especially when supported by institutions with a
               strong understanding of adaptation needs and capacity (high confidence). {4.8, 5.14, 6.4, Table 6.10, 7.4, 9.4, Table 11.17, 12.5, 13.11,
               15.6, 17.4, 18.4, Box 18.9, CCP5.4, CCB FINANCE}

      C.5.5    Monitoring and evaluation (M&E) of adaptation are critical for tracking progress and enabling effective adaptation (high confidence).
               M&E implementation is currently limited (high confidence) but has increased since AR5 at local and national levels. Although most of
               the monitoring of adaptation is focused towards planning and implementation, the monitoring of outcomes is critical for tracking the
               effectiveness and progress of adaptation (high confidence). M&E facilitates learning on successful and effective adaptation measures,
               and signals when and where additional action may be needed. M&E systems are most effective when supported by capacities and
               resources and embedded in enabling governance systems (high confidence). {1.4, 2.6, 6.4, 7.4, 11.7, 11.8, 13.2, 13.11, 17.5, 18.4,

      C.5.6    Inclusive governance that prioritises equity and justice in adaptation planning and implementation leads to more effective and
               sustainable adaptation outcomes (high confidence). Vulnerabilities and climate risks are often reduced through carefully designed and
               implemented laws, policies, processes, and interventions that address context specific inequities such as based on gender, ethnicity,
               disability, age, location and income (high confidence). These approaches, which include multi-stakeholder co-learning platforms,
               transboundary collaborations, community-based adaptation and participatory scenario planning, focus on capacity-building, and
               meaningful participation of the most vulnerable and marginalised groups, and their access to key resources to adapt (high confidence).
               {1.4, 2.6, 3.6, 4.8, 5.4, 5.8, 5.9, 5.13, 6.4, 7.4, 8.5, 11.8, 12.5, 13.11, 14.7, 15.5, 15.7, 17.3, 17.5, 18.4, CCP2.4, CCP5.4, CCP6.4, CCB

      D: Climate Resilient Development

      Climate resilient development integrates adaptation measures and their enabling conditions (Section C) with mitigation to advance sustainable
      development for all. Climate resilient development involves questions of equity and system transitions in land, ocean and ecosystems; urban
      and infrastructure; energy; industry; and society and includes adaptations for human, ecosystem and planetary health. Pursuing climate resilient
      development focuses on both where people and ecosystems are co-located as well as the protection and maintenance of ecosystem function at
      the planetary scale. Pathways for advancing climate resilient development are development trajectories that successfully integrate mitigation and
      adaptation actions to advance sustainable development. Climate resilient development pathways may be temporarily coincident with any RCP
      and SSP scenario used throughout AR6, but do not follow any particular scenario in all places and over all time.

                                                                                                                        Summary for Policymakers

Conditions for Climate Resilient Development

D.1     Evidence of observed impacts, projected risks, levels and trends in vulnerability, and adaptation limits, demonstrate that
        worldwide climate resilient development action is more urgent than previously assessed in AR5. Comprehensive, effective,
        and innovative responses can harness synergies and reduce trade-offs between adaptation and mitigation to advance
        sustainable development. (very high confidence) {2.6, 3.4, 3.6, 4.2, 4.6, 7.2, 7.4, 8.3, 8.4, 9.3, 10.6, 13.3, 13.8, 13.10, 14.7,
        17.2, 18.3, Box 18.1, Figure 18.1, Table 18.5}                                                                                                    SPM

D.1.1   There is a rapidly narrowing window of opportunity to enable climate resilient development. Multiple climate resilient development
        pathways are still possible by which communities, the private sector, governments, nations and the world can pursue climate resilient
        development – each involving and resulting from different societal choices influenced by different contexts and opportunities and
        constraints on system transitions. Climate resilient development pathways are progressively constrained by every increment of
        warming, in particular beyond 1.5°C, social and economic inequalities, the balance between adaptation and mitigation varying by
        national, regional and local circumstances and geographies, according to capabilities including resources, vulnerability, culture and
        values, past development choices leading to past emissions and future warming scenarios, bounding the climate resilient development
        pathways remaining, and the ways in which development trajectories are shaped by equity, and social and climate justice. (very high
        confidence) {Figure TS.14d, 2.6, 4.7, 4.8, 5.14, 6.4, 7.4, 8.3, 9.4, 9.3, 9.4, 9.5, 10.6, 11.8, 12.5, 13.10, 14.7, 15.3, 18.5, CCP2.3, CCP3.4,
        CCP4.4, CCP5.3, CCP5.4, Table CCP5.2, CCP6.3, CCP7.5}

D.1.2   Opportunities for climate resilient development are not equitably distributed around the world (very high confidence). Climate impacts
        and risks exacerbate vulnerability and social and economic inequities and consequently increase persistent and acute development
        challenges, especially in developing regions and sub-regions, and in particularly exposed sites, including coasts, small islands, deserts,
        mountains and polar regions. This in turn undermines efforts to achieve sustainable development, particularly for vulnerable and
        marginalized communities (very high confidence). {2.5, 4.4, 4.7, 6.3, Box 6.4, Figure 6.5, 9.4, Table 18.5, CCP2.2, CCP3.2, CCP3.3,

D.1.3   Embedding effective and equitable adaptation and mitigation in development planning can reduce vulnerability, conserve and restore
        ecosystems, and enable climate resilient development. This is especially challenging in localities with persistent development gaps
        and limited resources (high confidence). Dynamic trade-offs and competing priorities exist between mitigation, adaptation, and
        development. Integrated and inclusive system-oriented solutions based on equity and social and climate justice reduce risks and enable
        climate resilient development (high confidence). {1.4, 2.6, Box 2.2, 3.6, 4.7, 4.8, Box 4.5, Box 4.8, 5.13, 7.4, 8.5, 9.4, Box 9.3, 10.6, 12.5,
        12.6, 13.3, 13.4, 13.10, 13.11, 14.7, 18.4, CCB DEEP, CCP2, CCP5.4, CCB HEALTH, SRCCL}

Enabling Climate Resilient Development

D.2     Climate resilient development is enabled when governments, civil society and the private sector make inclusive de-
        velopment choices that prioritise risk reduction, equity and justice, and when decision-making processes, finance and
        actions are integrated across governance levels, sectors and timeframes (very high confidence). Climate resilient devel-
        opment is facilitated by international cooperation and by governments at all levels working with communities, civil
        society, educational bodies, scientific and other institutions, media, investors and businesses; and by developing partner-
        ships with traditionally marginalised groups, including women, youth, Indigenous Peoples, local communities and ethnic
        minorities (high confidence). These partnerships are most effective when supported by enabling political leadership,
        institutions, resources, including finance, as well as climate services, information and decision support tools (high confi-
        dence). (Figure SPM.5) {1.3, 1.4, 1.5, 2.7, 3.6, 4.8, 5.14, 6.4, 7.4, 8.5, 8.6, 9.4, 10.6, 11.8, 12.5, 13.11, 14.7, 15.6, 15.7, 17.4,
        17.6, 18.4, 18.5, CCP2.4, CCP3.4, CCP4.4, CCP5.4, CCP6.4, CCP7.6, CCB DEEP, CCB GENDER, CCB HEALTH, CCB INDIG, CCB

D.2.1   Climate resilient development is advanced when actors work in equitable, just and enabling ways to reconcile divergent interests, values
        and worldviews, toward equitable and just outcomes (high confidence). These practices build on diverse knowledges about climate
        risk and chosen development pathways account for local, regional and global climate impacts, risks, barriers and opportunities (high
        confidence). Structural vulnerabilities to climate change can be reduced through carefully designed and implemented legal, policy, and
        process interventions from the local to global that address inequities based on gender, ethnicity, disability, age, location and income
        (very high confidence). This includes rights-based approaches that focus on capacity-building, meaningful participation of the most
        vulnerable groups, and their access to key resources, including financing, to reduce risk and adapt (high confidence). Evidence shows that
        climate resilient development processes link scientific, Indigenous, local, practitioner and other forms of knowledge, and are more effective
        and sustainable because they are locally appropriate and lead to more legitimate, relevant and effective actions (high confidence).


     There is a rapidly narrowing window of opportunity to enable climate resilient development
      (a) Societal choices about adaptation,                                                 (b) Illustrative development pathways                                    (c) Actions and outcomes
      mitigation and sustainable development                                                                                                                          characterizing development pathways
      made in arenas of engagement

       Dimensions that enable actions towards
       higher climate resilient development                                                                                                                                            poverty

                                                                                                                                                                                                            Summary for Policymakers

                                                                                                                                                                                Ecosystem health
                                                                                                                                                                                Equity and justice
                                                                                                                                                                                   Low global
                          e                                                                                                                                                      warming levels
                                                                                                                                                                                    Low risk

                  Arenas of engagement:
                  Community                               Past conditions
                  Socio-cultural                             (emissions,       Present
                                                                                                                                              RESILIENT DEVELOPMENT

                  Political                               climate change,     situation
                  Ecological                               development)
                  Knowledge + technology
                  Economic + financial

                          e                                                                                                                                                        Vulnerability
                                                                                                                                                                                   High poverty
                                                                                                                                                                              Ecosystem degradation

                                                                                                                                                                               Inequity and injustice

                                                                                                                                                                                    High global
                                                                                                                                                                                  warming levels
                                                                                                                                                                                     High risk

                                                                                                                                     2100 &
       Dimensions that result in actions towards                            2022                               2030                  beyond
       lower climate resilient development
                                                                            IPCC                          Sustainable
                                                                            AR6                        Development Goals

                                                                                                                                              Narrowing window of
            Illustrative climatic or non-climatic shock, e.g. COVID-19, drought or floods, that disrupts the development pathway              opportunity for higher CRD
                                                                                                                                                                  Summary for Policymakers

Figure SPM.5 | Climate resilient development (CRD) is the process of implementing greenhouse gas mitigation and adaptation measures to support sustainable
development. This figure builds on Figure SPM.9 in AR5 WGII (depicting climate resilient pathways) by describing how CRD pathways are the result of cumulative societal choices
and actions within multiple arenas.
Panel (a) Societal choices towards higher CRD (green cog) or lower CRD (red cog) result from interacting decisions and actions by diverse government, private sector
and civil society actors, in the context of climate risks, adaptation limits and development gaps. These actors engage with adaptation, mitigation and development actions in
political, economic and financial, ecological, socio-cultural, knowledge and technology, and community arenas from local to international levels. Opportunities for climate resilient
development are not equitably distributed around the world.
Panel (b) Cumulatively, societal choices, which are made continuously, shift global development pathways towards higher (green) or lower (red) climate resilient development.                                SPM
Past conditions (past emissions, climate change and development) have already eliminated some development pathways towards higher CRD (dashed green line).
Panel (c) Higher CRD is characterised by outcomes that advance sustainable development for all. Climate resilient development is progressively harder to achieve with global
warming levels beyond 1.5°C. Inadequate progress towards the Sustainable Development Goals (SDGs) by 2030 reduces climate resilient development prospects. There is a
narrowing window of opportunity to shift pathways towards more climate resilient development futures as reflected by the adaptation limits and increasing climate risks, considering
the remaining carbon budgets. (Figure SPM.2, Figure SPM.3) {Figure TS.14b, 2.6, 3.6, 7.2, 7.3, 7.4, 8.3, 8.4, 8.5, 16.4, 16.5, 17.3, 17.4, 17.5, 18.1, 18.2, 18.3, 18.4, Box 18.1,
Figure 18.1, Figure 18.2, Figure 18.3, CCB COVID, CCB GENDER, CCB HEALTH, CCB INDIG, CCB SLR, WGI AR6 Table SPM.1, WGI AR6 Table SPM.2, SR1.5 Figure SPM.1}

              Pathways towards climate resilient development overcome jurisdictional and organizational barriers, and are founded on societal
              choices that accelerate and deepen key system transitions (very high confidence). Planning processes and decision analysis tools
              can help identify ‘low regrets’ options47 that enable mitigation and adaptation in the face of change, complexity, deep uncertainty
              and divergent views (medium confidence). {1.3, 1.4, 1.5, 2.7, 3.6, 4.8, 5.14, 6.4, 7.4, 8.5, 8.6, Box 8.7, 9.4, Box 9.2, 10.6, 11.8, 12.5,
              13.11, 14.7, 15.6, 15.7, 17.2–17.6, 18.2–18.4, CCP2.3–2.4, CCP3.4, CCP4.4, CCP5.4, CCP6.4, CCP7.6, CCB DEEP, CCB HEALTH, CCB
              INDIG, CCB NATURAL, CCB SLR}

D.2.2         Inclusive governance contributes to more effective and enduring adaptation outcomes and enables climate resilient development (high
              confidence). Inclusive processes strengthen the ability of governments and other stakeholders to jointly consider factors such as the rate
              and magnitude of change and uncertainties, associated impacts, and timescales of different climate resilient development pathways
              given past development choices leading to past emissions and scenarios of future global warming (high confidence). Associated
              societal choices are made continuously through interactions in arenas of engagement from local to international levels. The quality
              and outcome of these interactions helps determine whether development pathways shift towards or away from climate resilient
              development (medium confidence). (Figure SPM.5) {2.7, 3.6, 4.8, 5.14, 6.4, 7.4, 8.5, 8.6, 9.4, 10.6, 11.8, 12.5, 13.11, 14.7, 15.6, 15.7,
              17.2–17.6, 18.2, 18.4, CCP2.3–2.4, CCP3.4, CCP4.4, CCP5.4, CCP6.4, CCP7.6, CCB GENDER, CCB HEALTH, CCB INDIG}

D.2.3         Governance for climate resilient development is most effective when supported by formal and informal institutions and practices that
              are well-aligned across scales, sectors, policy domains and timeframes. Governance efforts that advance climate resilient development
              account for the dynamic, uncertain and context-specific nature of climate-related risk, and its interconnections with non-climate
              risks. Institutions48 that enable climate resilient development are flexible and responsive to emergent risks and facilitate sustained
              and timely action. Governance for climate resilient development is enabled by adequate and appropriate human and technological
              resources, information, capacities and finance. (high confidence) {2.7, 3.6, 4.8, 5.14, 6.3, 6.4, 7.4, 8.5, 8.6, 9.4, 10.6, 11.8, 12.5, 13.11,
              14.7, 15.6, 15.7, 17.2-17.6, 18.2, 18.4, CCP2.3–2.4, CCP3.4, CCP4.4, CCP5.4, CCP6.4, CCP7.6, CCB DEEP, CCB GENDER, CCB HEALTH,

Climate Resilient Development for Natural and Human Systems

D.3           Interactions between changing urban form, exposure and vulnerability can create climate change-induced risks and losses
              for cities and settlements. However, the global trend of urbanisation also offers a critical opportunity in the near-term,
              to advance climate resilient development (high confidence). Integrated, inclusive planning and investment in everyday
              decision-making about urban infrastructure, including social, ecological and grey/physical infrastructures, can significantly
              increase the adaptive capacity of urban and rural settlements. Equitable outcomes contributes to multiple benefits for
              health and well-being and ecosystem services, including for Indigenous Peoples, marginalised and vulnerable communi-
              ties (high confidence). Climate resilient development in urban areas also supports adaptive capacity in more rural places
              through maintaining peri-urban supply chains of goods and services and financial flows (medium confidence). Coastal
              cities and settlements play an especially important role in advancing climate resilient development (high confidence).
              {6.2, 6.3, Table 6.6, 7.4, 8.6, Box 9.8, 18.3, CCP2.1. CCP2.2, CCP6.2, CWGB URBAN}

48    Institutions: Rules, norms and conventions that guide, constrain or enable human behaviours and practices. Institutions can be formally established, for instance through laws and regulations, or
      informally established, for instance by traditions or customs. Institutions may spur, hinder, strengthen, weaken or distort the emergence, adoption and implementation of climate action and climate

      Summary for Policymakers

      D.3.1         Taking integrated action for climate resilience to avoid climate risk requires urgent decision making for the new built environment
                    and retrofitting existing urban design, infrastructure and land use. Based on socioeconomic circumstances, adaptation and
                    sustainable development actions will provide multiple benefits including for health and well-being, particularly when supported by
                    national governments, non-governmental organisations and international agencies that work across sectors in partnerships with
                    local communities. Equitable partnerships between local and municipal governments, the private sector, Indigenous Peoples, local
                    communities, and civil society can, including through international cooperation, advance climate resilient development by addressing
SPM                 structural inequalities, insufficient financial resources, cross-city risks and the integration of Indigenous knowledge and local
                    knowledge. (high confidence) {6.2, 6.3, 6.4, Table 6.6, 7.4, 8.5, 9.4, 10.5. 12.5, 17.4, Table 17.8, 18.2, Box 18.1, CCP2.4, CCB FINANCE,
                    CCB GENDER, CCB INDIG, CWGB URBAN}

      D.3.2         Rapid global urbanisation offers opportunities for climate resilient development in diverse contexts from rural and informal settlements
                    to large metropolitan areas (high confidence). Dominant models of energy intensive and market-led urbanisation, insufficient and
                    misaligned finance and a predominant focus on grey infrastructure in the absence of integration with ecological and social approaches,
                    risks missing opportunities for adaptation and locking in maladaptation (high confidence). Poor land use planning and siloed approaches
                    to health, ecological and social planning also exacerbates, vulnerability in already marginalised communities (medium confidence).
                    Urban climate resilient development is observed to be more effective if it is responsive to regional and local land use development
                    and adaptation gaps, and addresses the underlying drivers of vulnerability (high confidence). The greatest gains in well-being can be
                    achieved by prioritizing finance to reduce climate risk for low-income and marginalized residents including people living in informal
                    settlements (high confidence). {5.14, 6.1, 6.2, 6.3, 6.4, 6.5, Figure 6.5, Table 6.6, 7.4, 8.5, 8.6, 9.8, 9.9, 10.4, Table 17.8, 18.2, CCP2.2,
                    CCP5.4, CCB HEALTH, CWGB URBAN}

      D.3.3         Urban systems are critical, interconnected sites for enabling climate resilient development, especially at the coast. Coastal cities and
                    settlements play a key role in moving toward higher climate resilient development given firstly, almost 11% of the global population –
                    896 million people – lived within the Low Elevation Coastal Zone49 in 2020, potentially increasing to beyond 1 billion people by 2050,
                    and these people, and associated development and coastal ecosystems, face escalating climate compounded risks, including sea level
                    rise. Secondly, these coastal cities and settlements make key contributions to climate resilient development through their vital role in
                    national economies and inland communities, global trade supply chains, cultural exchange, and centres of innovation. (high confidence)
                    {6.1, 6.2, 6.4, Table 6.6, Box 15.2, SMCCP Table 2.1, CCP2.2, CCP2.4, CCB SLR, XWGB URBAN, SROCC Chapter 4}

      D.4           Safeguarding biodiversity and ecosystems is fundamental to climate resilient development, in light of the threats climate
                    change poses to them and their roles in adaptation and mitigation (very high confidence). Recent analyses, drawing on a
                    range of lines of evidence, suggest that maintaining the resilience of biodiversity and ecosystem services at a global scale
                    depends on effective and equitable conservation of approximately 30% to 50% of Earth’s land, freshwater and ocean
                    areas, including currently near-natural ecosystems (high confidence). {2.4, 2.5, 2.6, 3.4, 3.5, 3.6, Box 3.4, 12.5, 13.3, 13.4,
                    13.5, 13.10, CCB INDIG, CCB NATURAL}

      D.4.1         Building the resilience of biodiversity and supporting ecosystem integrity50 can maintain benefits for people, including livelihoods,
                    human health and well-being and the provision of food, fibre and water, as well as contributing to disaster risk reduction and climate
                    change adaptation and mitigation. {2.2, 2.5, 2.6, Table 2.6, Table 2.7, 3.5, 3.6, 5.8, 5.13, 5.14, Box 5.11, 12.5, CCP5.4, CCB COVID, CCB

      D.4.2         Protecting and restoring ecosystems is essential for maintaining and enhancing the resilience of the biosphere (very high
                    confidence). Degradation and loss of ecosystems is also a cause of greenhouse gas emissions and is at increasing risk of being
                    exacerbated by climate change impacts, including droughts and wildfire (high confidence). Climate resilient development
                    avoids adaptation and mitigation measures that damage ecosystems (high confidence). Documented examples of adverse impacts of
                    land-based measures intended as mitigation, when poorly implemented, include afforestation of grasslands, savannas and peatlands,
                    and risks from bioenergy crops at large scale to water supply, food security and biodiversity (high confidence). {2.4, 2.5, Box 2.2, 3.4,
                    3.5, Box 3.4, Box 9.3, CCP7.3, CCB NATURAL, CWGB BIOECONOMY}

      49    LECZ, coastal areas below 10 m of elevation above sea level that are hydrologically connected to the sea.
      50    Ecosystem integrity refers to the ability of ecosystems to maintain key ecological processes, recover from disturbance, and adapt to new conditions.

                                                                                                                       Summary for Policymakers

D.4.3   Biodiversity and ecosystem services have limited capacity to adapt to increasing global warming levels, which will make climate resil-
        ient development progressively harder to achieve beyond 1.5°C warming (very high confidence). Consequences of current and future
        global warming for climate resilient development include reduced effectiveness of Ecosystem-based Adaptation and approaches to
        climate change mitigation based on ecosystems and amplifying feedbacks to the climate system (high confidence). {Figure TS.14d, 2.4,
        2.5, 2.6, 3.4, Box 3.4, 3.5, 3.6, Table 5.2, 12.5, 13.2, 13.3, 13.10, 14.5, 14.5, Box 14.3, 15.3, 17.3, 17.6, CCP5.3, CCP5.4, CCB EXTREMES,

Achieving Climate Resilient Development

D.5     It is unequivocal that climate change has already disrupted human and natural systems. Past and current development
        trends (past emissions, development and climate change) have not advanced global climate resilient development (very
        high confidence). Societal choices and actions implemented in the next decade determine the extent to which medium-
        and long-term pathways will deliver higher or lower climate resilient development (high confidence). Importantly climate
        resilient development prospects are increasingly limited if current greenhouse gas emissions do not rapidly decline, es-
        pecially if 1.5°C global warming is exceeded in the near-term (high confidence). These prospects are constrained by past
        development, emissions and climate change, and enabled by inclusive governance, adequate and appropriate human and
        technological resources, information, capacities and finance (high confidence). {Figure TS.14d, 1.2, 1.4, 1.5, 2.6, 2.7, 3.6,
        4.7, 4.8, 5.14, 6.4, 7.4, 8.3, 8.5, 8.6, 9.3, 9.4, 9.5, 10.6, 11.8, 12.5, 13.10, 13.11, 14.7, 15.3, 15.6, 15.7, 16.2, 16.4, 16.5, 16.6,
        17.2–17.6, 18.2–18.5, CCP2.3–2.4, CCP3.4, CCP4.4, CCP5.3, CCP5.4, Table CCP5.2, CCP6.3, CCP6.4, CCP7.5, CCP7.6, CCB

D.5.1   Climate resilient development is already challenging at current global warming levels (high confidence). The prospects for climate
        resilient development will be further limited if global warming levels exceeds 1.5°C (high confidence) and not be possible in some
        regions and sub-regions if the global warming level exceeds 2°C (medium confidence). Climate resilient development is most
        constrained in regions/subregions in which climate impacts and risks are already advanced, including low-lying coastal cities and
        settlements, small islands, deserts, mountains and polar regions (high confidence). Regions and subregions with high levels of poverty,
        water, food and energy insecurity, vulnerable urban environments, degraded ecosystems and rural environments, and/or few enabling
        conditions, face many non-climate challenges that inhibit climate resilient development which are further exacerbated by climate
        change (high confidence). {Figure TS.14d, 1.2, Box 6.6, 9.3, 9.4, 9.5, 10.6, 11.8, 12.5, 13.10, 14.7, 15.3, CCP2.3, CCP3.4, CCP4.4, CCP5.3,
        Table CCP5.2, CCP6.3, CCP7.5}

D.5.2   Inclusive governance, investment aligned with climate resilient development, access to appropriate technology and rapidly
        scaled-up finance, and capacity building of governments at all levels, the private sector and civil society enable climate resilient
        development. Experience shows that climate resilient development processes are timely, anticipatory, integrative, flexible and action
        focused. Common goals and social learning build adaptive capacity for climate resilient development. When implementing adaptation
        and mitigation together, and taking trade-offs into account, multiple benefits and synergies for human well-being as well as ecosystem
        and planetary health can be realised. Prospects for climate resilient development are increased by inclusive processes involving local
        knowledge and Indigenous Knowledge as well as processes that coordinate across risks and institutions. Climate resilient development
        is enabled by increased international cooperation including mobilising and enhancing access to finance, particularly for vulnerable
        regions, sectors and groups. (high confidence) (Figure SPM.5) {2.7, 3.6, 4.8, 5.14, 6.4, 7.4, 8.5, 8.6, 9.4, 10.6, 11.8, 12.5, 13.11, 14.7,
        15.6, 15.7, 17.2–17.6, 18.2–18.5, CCP2.3–2.4, CCP3.4, CCP4.4, CCP5.4, CCP6.4, CCP7.6, CCB DEEP, CCB HEALTH, CCB INDIG, CCB

D.5.3   The cumulative scientific evidence is unequivocal: Climate change is a threat to human well-being and planetary health. Any further
        delay in concerted anticipatory global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity
        to secure a liveable and sustainable future for all. (very high confidence) {1.2, 1.4, 1.5, 16.2, Table SM16.24, 16.4, 16.5, 16.6, 17.4, 17.5,
        17.6, 18.3, 18.4, 18.5, CCB DEEP, CWGB URBAN, WGI AR6 SPM, SROCC SPM, SRCCL SPM}