In recent years, assessment of adaptive capacity has emerged as a critical focus of attention, for two reasons: the realization that the Kyoto Protocol is inadequate to prevent substantial changes in climate, and the rising expectation that social and natural systems can cope with climate change, at least within limits, and that adaptation is a viable option to reduce GHG emissions.

Although there are numerous examples of model calculations for adaptive shifts in flora, far less attention has been paid to assessing the adaptability of the system as a whole (e.g., White et al., 1999). In contrast with other phenomena, such as changes in the water cycle, changes in natural ecosystems are related to a long-term process of adaptation and extinction. As noted above, transient climate change scenarios have become a mainstream research procedure.

The recent literature concerned with the impacts of climate change on the managed environment [e.g., on agriculture (see Section 5.3) and coastal zones (see Section 6.7)] generally considers adaptive strategies (e.g., Rosenzweig and Parry, 1994). Water management, for example, has a long history of evaluation of strategies for adapting to climate change and variation (Frederick et al., 1997). However, adaptation often is approached narrowly in terms of technological options. Adaptation processes—including the environmental, behavioral, economic, institutional, and cultural factors that serve as barriers or incentives to adaptation over time—often are not considered.

Five methodological directions could enhance future work on adaptation (see Chapter 18). First, methods for increasing understanding of the relationship between adaptation, individual decisionmaking, and local conditions are required. For example, adaptation by farmers could avoid more than half of the potential impacts of climate change on agriculture (e.g., Darwin et al., 1995; El-Shaer et al., 1997). The mix of appropriate measures depends, however, on the local context of soils, climates, economic infrastructure, and other resources (Rosenzweig and Tubiello, 1997) and how they are perceived by farmers. Assessments of adaptation could address these issues of site-scale characteristics and local knowledge, perhaps through participatory methods (e.g., Cohen, 1997, 1998) or interviews and expert opinion (as in the UK Climate Impacts Programme—Mackenzie-Hedger et al., 2000; see <http://www.ukcip.org>).

Second, interactions across scale are likely to be significant for adaptation. In the agricultural sector, for example, adaptive strategies are influenced by multi-scale factors—at the farm, national, and global levels—and their integration into decisionmaking. Methods and tools for examining these multi-scale interactions and their implications for adaptation are required, such as multi-level modeling (Easterling et al., 1998), integrated assessment (see Section 2.4), and agent-based simulation (Downing et al., 2000).

Third, specific measures (such as changing planting dates and cultivars) and longer term adaptation strategies and processes (such as monitoring and research) need to be addressed. Many studies focus on the former; assessing the latter is a major methodological challenge.

Fourth, comparative frameworks are required for assessing the priority of adaptation strategies across populations, regions, and sectors, in addition to evaluating specific measures. Fankhauser (1998) devised a list of adaptation policy options, discussed conceptual issues of economic evaluation, and illustrated typical cost/benefit calculation methods. Section 2.5 considers the use of economic evaluation methods, but nonmonetary frameworks are alternatives (see Huq et al., 1999, for a case example). Issues of equity and valuation on indirect benefits and costs are salient.

Fifth, adaptation to extremes and variability already are important areas of assessment (see above) but need to be more explicitly tied to longer term climate change.

Sixth, stakeholder evaluation of adaptation strategies and measures is required—for example, using decision analytical tools, as noted in Section 2.7. Indicators of vulnerability could be used to monitor the effectiveness of adaptative strategies and measures (see Downing et al., 2001)

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