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

5.2.3 Current vulnerability and adaptive capacity in perspective

Current vulnerability to climate variability, including extreme events, is both hazard- and context-dependent (Brooks et al., 2005). For agriculture, forestry and fisheries systems, vulnerability depends on exposure and sensitivity to climate conditions (as discussed above), and on the capacity to cope with changing conditions. A comparison of conditions on both sides of the USA–Mexico border reveals how social, political, economic and historical factors contribute to differential vulnerability among farmers and ranchers living within the same biophysical regime (Vasquez-Leon et al., 2003). Institutional and economic reforms linked to globalisation processes (e.g., removal of subsidies, increased import competition) reduce the capacity of some farmers to respond to climate variability (O’Brien et al., 2004). Efforts to reduce vulnerability and facilitate adaptation to climate change are influenced both positively and negatively by changes associated with globalisation (Eakin and Lemos, 2006).

Adaptive capacity with respect to current climate is dynamic, and influenced by changes in wealth, human capital, information and technology, material resources and infrastructure, and institutions and entitlements (see Chapter 17) (Yohe and Tol, 2001; Eakin and Lemos, 2006). The production and dissemination of seasonal climate forecasts has improved the ability of many resource managers to anticipate and plan for climate variability, particularly in relation to ENSO, but with some limitations (Harrison, 2005). However, problems related to infectious disease, conflicts and other societal factors may decrease the capacity to respond to variability and change at the local level, thereby increasing current vulnerability. Policies and responses made at national and international levels also influence local adaptations (Salinger et al., 2005). National agricultural policies are often developed on the basis of local risks, needs and capacities, as well as international markets, tariffs, subsidies and trade agreements (Burton and Lim, 2005).

Sub-Saharan Africa is one example of an area of the world that is currently highly vulnerable to food insecurity (Vogel, 2005). Drought conditions, flooding and pest outbreaks are some of the current stressors on food security that may be influenced by future climate change. Current response options and overall development initiatives related to agriculture, fisheries and forestry may be constrained by health status, lack of information and ineffective institutional structures, with potentially negative consequences for future adaptations to periods of heightened climate stress (see Chapter 9) (Reid and Vogel, 2006).