IPCC Fourth Assessment Report: Climate Change 2007
Climate Change 2007: Working Group II: Impacts, Adaptation and Vulnerability

7.6.7 Key adaptation issues

The central issues for adaptation to climate change by industry, settlements and society are (a) impact types and magnitudes and their associated adaptation requirements, (b) potential contributions by adaptation strategies to reducing stresses and impacts, (c) costs of adaptation strategies relative to benefits, and (d) limits of adaptation in reducing stresses and impacts under realistically conceivable sets of policy and investment conditions (Downing, 2003). Underlying all of these issues, of course, is the larger issue of the adaptive capacity of a population, a community, or an organisation: the degree to which it can (or is likely to) act, through individual agency or collective policies, to reduce stresses and increase coping capacities (Chapter 17). In many cases, this capacity differs significantly between developing and developed countries, and it may differ considerably among locations, economic sectors and populations even within the same region (Millennium Ecosystem Assessment, 2005).

Many of the possibly-impacted activities and groups addressed by this chapter are capable of being highly adaptable over time, given information to inform awareness of possible risks and opportunities and financial and human resources for responses (Chapter 17). In some cases, adaptations to possible climate changes can offer opportunities for positive impacts, especially where those actions also address other adaptive management issues (Chapter 20). The knowledge base on disaster response suggests that a number of approaches may be helpful in enhancing and facilitating adaptive behaviour: systems to provide advance warning of changes, especially extreme events; institutional structures that facilitate collective action and provide external linkages; economic systems that offer access to alternatives; increased attention to adaptive structures that are locally appropriate, geographically and/or sectorally; contingency planning and risk financing, which may include strategic stockpiles; incorporating climate-change vulnerability into land-use planning and environmental management for the long term; public awareness/capacity building regarding risks of climate-change impacts; and in some cases physical facility investment, such as flood walls, beach restoration or emergency shelters.

Although the research literatures on adaptation prospects for industry, settlement and society are as yet rather limited, it appears that:

1. Prospects for adaptation depend on the magnitude and rate of climate change: adaptation is more feasible when climate change is moderate and gradual than when it is massive and/or abrupt. However, actual adaptation strategies and measures are often triggered by relatively extreme weather events (high confidence).

2. Climate-change adaptation strategies are inseparable from increasingly strong and complex global linkages. Industrial planning, human settlements and social development are not isolated from changes in other systems or scales. The urban and rural are interconnected, as are developed and developing societies. This issue is becoming more salient as the globalised economy becomes more interdependent. Adaptation decisions for local activities owned or controlled by external systems involve different processes from adaptation decisions for local activities that are under local control (high confidence).

3. Climate change is one of many challenges to human institutions to manage risks. In any society, institutions have developed risk management mechanisms for such purposes, from family and community self-help to insurance and re-insurance. It is not clear whether, where and to what degree existing risk management structures are adequate for climate change; but these institutions have considerable potential to be foundations for a number of kinds of adaptations (high confidence).

4. Adaptation actions can be effective in achieving their specific goals, but they may have other effects as well. These might be unintended consequences (e.g., increased flood risk downstream), reducing support for mitigation (e.g., higher energy demand with air-conditioning), or reducing resources available to address vulnerabilities elsewhere (e.g., budget constraints affecting other development goals). The benefits of adaptation may be delayed or not realised at all, for example, when design standards are raised to protect against a storm of a certain magnitude that does not occur for another fifty years, if then (medium confidence).