Adaptation to climate change and risks takes place in a dynamic social, economic, technological, biophysical, and political context that varies over time, location, and sector. This complex mix of conditions determines the capacity of systems to adapt. Although scholarship on adaptive capacity is extremely limited in the climate change field, there is considerable understanding of the conditions that influence the adaptability of societies to climate stimuli in the fields of hazards, resource management, and sustainable development. From this literature, it is possible to identify the main features of communities or regions that seem to determine their adaptive capacity: economic wealth, technology, information and skills, infrastructure, institutions, and equity.
Whether it is expressed as the economic assets, capital resources, financial means, wealth, or poverty, the economic condition of nations and groups clearly is a determinant of adaptive capacity (Burton et al., 1998; Kates, 2000). It is widely accepted that wealthy nations are better prepared to bear the costs of adaptation to climate change impacts and risks than poorer nations (Goklany, 1995; Burton, 1996). It is also recognized that poverty is directly related to vulnerability (Chan and Parker, 1996; Fankhauser and Tol, 1997; Rayner and Malone, 1998). Although poverty should not be considered synonymous with vulnerability, it is "a rough indicator of the ability to cope" (Dow, 1992). Holmes (1996) recognizes that Hong Kong's financial strength has contributed in the past to its ability to better manage environmental hazards through conservation and pollution control. Bohle et al. (1994) state that, by definition, it usually is the poor who are among the most vulnerable to famine, malnutrition, and hunger. Deschingkar (1998) describes a situation in India in which pastoralist communities are "locked into" a vulnerable situation in part because of a lack of financial power that would allow them to diversify and engage in other sources of income. At a local level, Pelling (1998) concludes that the highest levels of household vulnerability in coastal Guyana also are characterized by low household incomes in conjunction with poor housing quality and little community organization. Neighborhoods with higher levels of household income are better able to manage vulnerability through the transfer of flood impacts from health to economic investment and loss. Kelly and Adger (1999) demonstrate the influence of poverty on a region's coping capacity; poor regions tend to have less diverse and more restricted entitlements and a lack of empowerment to adapt. There is ample evidence that poorer nations and disadvantaged groups within nations are especially vulnerable to disasters (Banuri, 1998; Munasinghe, 2000).
Lack of technology has the potential to seriously impede a nation's ability to implement adaptation options by limiting the range of possible responses (Scheraga and Grambsch, 1998). Adaptive capacity is likely to vary, depending on availability and access to technology at various levels (i.e., from local to national) and in all sectors (Burton, 1996). Many of the adaptive strategies identified as possible in the management of climate change directly or indirectly involve technology (e.g., warning systems, protective structures, crop breeding and irrigation, settlement and relocation or redesign, flood control measures). Hence, a community's current level of technology and its ability to develop technologies are important determinants of adaptive capacity. Moreover, openness to the development and utilization of new technologies for sustainable extraction, use, and development of natural resources is key to strengthening adaptive capacity (Goklany, 1995). For example, in the context of Asian agriculture and the impact of future climate change, Iglesias et al. (1996) note that the development of heat-resistant rice cultivars will be especially crucial. Regions with the ability to develop technology have enhanced adaptive capacity.
"Successful adaptation requires a recognition of the necessity to adapt, knowledge about available options, the capacity to assess them, and the ability to implement the most suitable ones" (Fankhauser and Tol, 1997). In the context of climate variability and change, this idea may be better understood through the example of the insurance industry: As information on weather hazards becomes more available and understood, it is possible to study, discuss, and implement adaptation measures (Downing, 1996). Building adaptive capacity requires a strong, unifying vision; scientific understanding of the problems; an openness to face challenges; pragmatism in developing solutions; community involvement; and commitment at the highest political level (Holmes, 1996). Lack of trained and skilled personnel can limit a nation's ability to implement adaptation options (Scheraga and Grambsch, 1998). In general, countries with higher levels of stores of human knowledge are considered to have greater adaptive capacity than developing nations and those in transition (Smith and Lenhart, 1996). Magalhães (1996) includes illiteracy along with poverty as a key determinant of low adaptive capacity in northeast Brazil. Such findings have prompted Gupta and Hisschemöller (1997) to conclude that it is important, therefore, to ensure that systems are in place for the dissemination of climate change and adaptation information nationally and regionally and that there are forums for discussion and innovation of adaptation strategies at various levels.
Adaptive capacity is likely to vary with social infrastructure (Toman and Bierbaum, 1996). Some researchers regard the adaptive capacity of a system as a function of availability of and access to resources by decisionmakers, as well as vulnerable subsectors of a population (Kelly and Adger, 1999). For example, the Philippine island of Mindanao uses hydroelectric power to generate more than 90% of its electricity, which in turn supports local development and industry. During El Niño, drought conditions resulted in suspension of production by the hydroelectric plant and severely increased the economic vulnerability of the region (Tiglao, 1992). In the coastal area of Hong Kong, the capacity to adapt to the risk of typhoons differs for existing urban areas and for new coastal land reclamation. For existing urban areas, there is no possibility of retreat or accommodation, although during urban renewal the formation level of the ground could be raised, thereby decreasing the vulnerability of settlements (Yim, 1996). At the community level, Pelling (1997) notes that the lack of flexibility "in formal housing areas where dwelling form and drainage infrastructure were more fixed" reduced the capacity to respond to contemporary environmental conditions.
O'Riordan and Jordan (1999) describe the role of institutions "as a means for holding society together, giving it sense and purpose and enabling it to adapt." In general, countries with well-developed social institutions are considered to have greater adaptive capacity than those with less effective institutional arrangementscommonly, developing nations and those in transition (Smith and Lenhart, 1996). The role of inadequate institutional support is frequently cited in the literature as a hindrance to adaptation. Kelly and Adger (1999) show how institutional constraints limit entitlements and access to resources for communities in coastal Vietnam and thereby increase vulnerability. Huq et al. (1999) demonstrate that Bangladesh is particularly vulnerable to climate changeespecially in the areas of food production, settlements, and human lifereflecting serious constraints on adaptive capacity in the "existing institutional arrangements (which) is not conducive to ease the hardship of the people. Due to inherent institutional deficiencies and weaknesses in managerial capacities to cope with the anticipated natural event, it would be extremely difficult for the country to reduce vulnerability to climate change" (Ahmed et al., 1999). Baethgen (1997) discusses an example in which the presence of inconsistent and unstable agricultural policies has increased the vulnerability of the food production sector in Latin America. Drastic changes in economic and policy conditions are expected to make agricultural systems more vulnerable to changes in climate. Parrish and Funnell (1999) note that although the local agro-ecosystem in the Moroccon High Atlas region may prove resilient to climate change initially, it is possible that the need to change tenure conditions and other arrangements may create conflicts that are beyond the capacity of local institutions to resolve. Magadza (2000) shows how adaptation options in southern Africa are precluded by political and institutional inefficiencies and resulting resource inequities.
It is generally held that established institutions in developed countries not only facilitate management of contemporary climate-related risks but also provide an institutional capacity to help deal with risks associated with future climate change. Stakhiv (1994) states that in the water resource sector, present-day strategies, demand management tools, and measures (i.e., institutions) have evolved over the past 25 years and are capable of serving as a basis for adaptive response strategies to climate change: "[T]he accumulation of numerous small changes in the present range of water resources management practices and procedures increases the flexibility for adaptation to current climate uncertainty and serves as a precursor to future possible responses with an ill-defined, changing climatic regime." However, some analyses are less sanguine about the ability of existing institutions to efficiently deal with climate change hazards. For example, Miller et al. (1997) note that "the time has come for innovative thinking on the question of how our water allocation institutions should function to improve our capacity to adapt to the uncertain but potentially large impacts of global climate change on regional water supplies. Given the climatic uncertainties and the very different institutional settings that have developed in this country, there is no simple prescription for adaptation."
It is frequently argued that adaptive capacity will be greater if social institutions and arrangements governing the allocation of power and access to resources within a community, nation, or the globe assure that access to resources is equitably distributed (Ribot et al., 1996; Mustafa, 1998; Adger, 1999; Handmer et al., 1999; Kelly and Adger, 1999; Rayner and Malone, 1999; Toth, 1999). The extent to which nations or communities are "entitled" to draw on resources greatly influences their adaptive capacity and their ability to cope (Adger and Kelly, 1999). Some people regard the adaptive capacity of a system as a function not only of the availability of resources but of access to those resources by decisionmakers and vulnerable subsectors of a population (Kelly and Adger, 1999). In the case of technological innovation, Cyert and Kumar (1996) show that differential distribution of information within an organization can impose constraints on adaptation strategies. Differentiation in demographic variables such as age, gender, ethnicity, educational attainment, and health often are cited in the literature as being related to the ability to cope with risk (Chan and Parker, 1996; Burton et al., 1998; Scheraga and Grambsch, 1998). Wisner's (1998) study of homeless people in Tokyo provides an example of a situation in which inequality in access to resources results in a diminished capacity to adapt to environmental risk. Homeless people generally occupy marginal areas that are more vulnerable to environmental hazards. An associated lack of financial resources and infrastructure restricts the availability of adaptation options. A study by Bolin and Stanford (1991) draws parallel conclusions about the marginalization of minority groups.
These determinants of adaptive capacity are not independent of each other,
nor are they mutually exclusive. Adaptive capacity is the outcome of a combination
of determinants and varies widely between countries and groups, as well as over
time. "Vulnerability varies spatially because national environments, housing
and social structure vary spatially. It varies temporally because people move
through different life stages with varying mixes of resources and liabilities"
(Uitto, 1998). Bohle et al. (1994) document variable vulnerability to climatic
variations of groups in Zimbabwe and its association with poverty, the macro-political
economy, and inequitable land distribution. Not only are conditions for adaptive
capacity diverse, they also behave differently in different countries and regions,
particularly depending on the level of development. These determinants represent
conditions that constrain or enhance the adaptive capacity and hence the vulnerability
of regions, nations, and communities.
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