Climate Change 2001: Working Group II: Impacts, Adaptation and Vulnerability

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18.8. Conclusions

Adaptation can significantly reduce adverse impacts of climate change. Adaptation is an important part of societal response to global climate change. Planned, anticipatory adaptation has the potential to reduce vulnerability and realize opportunities associated with climate change effects and hazards. There are numerous examples of successful adaptations that would apply to climate change risks and opportunities. Substantial reductions in climate change damages can be achieved, especially in the most vulnerable regions, through timely deployment of adaptation measures.

In the absence of planned adaptation, communities will adapt autonomously to changing climatic conditions, but not without costs and residual damages. Societies and economies have been making adaptations to climate for centuries. However, losses from climate-related extreme events are substantial and, in some sectors, increasing—indicating patterns of development that remain vulnerable to temporal variations in climatic conditions and to climate change. The ecological, social, and economic costs of relying on reactive, autonomous adaptation to the cumulative effects of climate change are substantial and largely avoidable through planned, anticipatory adaptation.

The key features of climate change for vulnerability and adaptation are those that relate to variability and extremes, not simply changed average conditions. In addition, the speed of changes in event frequency is important. Most communities, sectors, and regions are reasonably adaptable to changes in average conditions, unless those changes are particularly sudden or not smooth. However, these communities are more vulnerable and less adaptable to changes in the frequency and/or magnitude of conditions other than average, especially extremes. Changes in the frequency and magnitude of extremes underlie changes in mean conditions and thus are inherent in climate change; adaptation initiatives to these hazards are of particular need.

Implementation of adaptation policies, programs, and measures usually will have immediate as well as future benefits. Adaptations to current climate and climate-related risks (recurring droughts, storms, floods, and other extremes) generally are consistent with adaptation to changing and changed climatic conditions.

Adaptations to changing climatic conditions are more likely to be implemented if they are consistent with or integrated with decisions or programs that address nonclimatic stresses. Vulnerabilities associated with climate change rarely are experienced independent of nonclimatic conditions. Impacts of climatic stimuli are felt via economic or social stresses, and adaptations to climate (by individuals, communities, and governments) are evaluated and undertaken in light of these conditions. The costs of adaptation often are marginal to other management or development costs. To be effective, climate change adaptation must consider nonclimatic stresses and be consistent with existing policy criteria, development objectives, and management structures.

Adaptive capacity varies considerably among regions, countries, and socioeconomic groups. The ability to adapt and cope with climate change impacts is a function of wealth, technology, information, skills, infrastructure, institutions, and equity. Groups and regions with limited adaptive capacity are more vulnerable to climate change damages.

Development decisions, activities, and programs play important roles in modifying the adaptive capacity of communities and regions, yet they tend not to take into account risks associated with climate variability and change. This omission in the design and implementation of many recent and current development initiatives results in unnecessary additional losses to life, well-being, and investments in the short and longer terms.

Enhancement of adaptive capacity is necessary to reduce vulnerability, particularly for the most vulnerable regions, nations, and socioeconomic groups. Activities required for the enhancement of adaptive capacity are essentially equivalent to those that promote sustainable development and equity.

Current knowledge about adaptation and adaptive capacity is insufficient for reliable prediction of adaptations and for rigorous evaluation of planned adaptation options, measures, and policies of governments:

• Although climate change vulnerability studies now usually consider adaptation, they rarely go beyond identifying adaptation options that might be possible. There is little research on the dynamics of adaptation in human systems, the processes of adaptation decisionmaking, the conditions that stimulate or constrain adaptation, and the role of nonclimatic factors.
• There are serious limitations in existing evaluations of adaptation options. Economic benefits and costs are key criteria, but they are not sufficient to adequately determine the appropriateness of adaptation measures. There also has been little research to date on the roles and responsibilities of individuals, communities, corporations, private and public institutions, governments, and international organizations in adaptation.
• Given the scope and variety of specific adaptation options across sectors, individuals, communities, and locations and the variety of participants—private and public—involved in most adaptation initiatives, it is probably infeasible to systematically evaluate lists of particular adaptation measures. Improving and applying knowledge on the constraints and opportunities for enhancing adaptive capacity is necessary to reduce vulnerabilities.