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

7.8 Key uncertainties and research priorities

Because research on vulnerabilities and adaptation potentials of human systems has lagged behind research on physical environmental systems, ecological impacts and mitigation, uncertainties dominate the subject matter of this chapter. Key issues include (a) uncertainties about climate-change impacts at a relatively fine-grained geographic and sectoral scale, both harmful and beneficial, which undermine efforts to assess potential benefits from investments in adaptation; (b) improved understanding of indirect second and third order impacts: i.e., the trickle down of primary effects, such as temperature or precipitation change, storm behaviour change and sea-level rise, through interrelationships among human systems; (c) relationships between specific effects in one location and the well-being of other locations, through linkages in inflows/outflows and inter-regional trade and migration flows; (d) uncertainties about potentials, costs and limits of adaptation in keeping stressful impacts within acceptable limits, especially in developing countries and regions (see Parson et al., 2003); and (e) uncertainties about possible trends in societal, economic and technological change with or without climate change. A particular challenge is improving the capacity to provide more quantitative estimates of impacts and adaptation potentials under the sets of assumptions included in SRES and other climate-change scenarios and scenarios of greenhouse gas emissions stabilisation, especially for time horizons of interest to decision makers, such as 2020, 2050 and 2080.

All of these issues are very high priorities for research in both developed and developing countries, with certain differences in emphasis related to the different development contexts. As a broad generalisation, the primary impact issue for developed countries is the possibility of abrupt climate change, which could cause changes too rapid and disruptive even for a relatively developed country to absorb, at least over a period of several decades. High priorities include reducing uncertainty about the potential for adaptation to cope with climate-change impacts in the absence of abrupt climate change, considering possible responses to threats from low-probability/high consequence contingencies, and considering interactions between climate change and other stresses. The primary impact issue for developing countries is the possibility that climate change, combined with other stresses affecting sustainable development, could jeopardise livelihoods and societies in many regions. High priorities include improving the understanding of multiple-stress contexts for sustainable development and improving the understanding of climate-sensitive thresholds for components of sustainable development paths.

Some of these uncertainties call for careful location- and sector-specific research, including better information about the geographic distribution of vulnerabilities of settlements and societies at a relatively localised scale, emphasising especially vulnerable areas, such as coastal areas in lower-income developing countries, and especially vulnerable sectors, such as tourism, and possible financial thresholds regarding the insurability of climate-change impact risks. Others call for attention to cross-sectoral and multi-locational relationships between climate change, adaptation and mitigation (Chapter 18), including both complementarities and trade-offs in policy and investment strategies. Underlying all of these issues for industry, settlement and society are relationships between possible climate-change impact vulnerabilities and adaptation responses and broader processes of sustainable economic and social development, which suggest a need for a much greater emphasis on research that investigates such linkages. In some cases, because of the necessarily speculative nature of research about future contingencies, it is likely to be useful to consider past experiences with climate variability and analogues drawn from other experiences with managing risks and adapting to environmental changes and stresses (e.g., Abler, 2003). In many others, an important step will be to establish mechanisms for monitoring interactions between emerging climate changes and other processes and stresses in order both to learn from the observations and to provide early alerts regarding potential problems or opportunities.

Underlying all of these research needs are often very serious limitations on available data to support valid analysis, especially data on nature-society linkages and data on relatively detailed-scale contexts in both developed and developing countries (e.g., Wilbanks et al., 2003). If information about possible impacts, vulnerabilities and adaptation potentials for industry, settlement and society is to be substantially improved, serious attention is needed towards establishing improved data sources on human-environmental relationships in both developing and developed countries, improving the integration of physical and earth science data from space-based and in situ observation systems with socioeconomic data, and improving the ability to associate data systems with high-priority questions.