The Regional Impacts of Climate Change

	Other reports in this collection

1.3.3. Socioeconomic and Resource-Use Baseline Data

The vulnerability of ecosystems and socioeconomic sectors will be affected by their baseline or initial conditions and by the other stresses to which they may be subjected. For this reason, it is important to examine the vulnerability of these systems and sectors in the context of existing and projected developments. To provide a consistent set of socioeconomic and resource-use data, the Technical Support Unit collated data requested by the authors from, among other sources, World Resources 1996-97 (WRI/UNEP/UNDP/World Bank, 1996) (see Annex D for a complete list of sources). These data include information on:

• Population and related indicators (1995 population, current population density, projected population density for 2025, and urban and coastal populations)
• Economic indicators [gross domestic product (GDP) per capita; annual growth rate for GDP; and percentage of GDP from agriculture, industry, and services]
• Land cover and use (total land area and amount of land in several categories, including permanent cropland, permanent pasture, forest and woodland, and other land)
• Agricultural activities (amount of irrigated land, size of agricultural labor force, and livestock holdings)
• Water use (water resources per capita and annual water withdrawals for domestic uses, industry, and agriculture)
• Energy use (total commercial energy consumption and consumption of energy sources that are sensitive to changes in climate, including traditional fuels and hydroelectric production)
• Biodiversity (known and endemic mammal, bird, and plant species).

It is important to note that these data are intended simply to provide a consistent set of assumptions on important social and economic factors that will influence demands on environmental goods and services (and hence the stresses to which environmental systems may be subjected), as well as the human and financial capacity of societies to adapt to potential climate change. They are not intended to be a definitive source of data on social and economic trends in any particular country. Projections of socioeconomic conditions such as population, incomes, land uses, technological change, economic activity by sector, demands for water and other resources, and other variables are at least as uncertain as regional projections of climate change; as with regional climate information, they should be used as scenarios of future conditions, not treated as predictions.

1.3.4. Development of Integrated Socioeconomic and Climate Change Scenarios

It is important for policymakers to be able to put climate change impacts in the context of other social, economic, and technological conditions, such as:

• Demographic change
• Land-use change
• Land degradation
• Air and water pollution
• Economic and social change, "development" (including technological change), and poverty.

Thus, each chapter in this report has a section on "integrated assessment," which attempts to draw together the interactions among sectors, countries, and forces of change. Integrated assessment has been tackled at various levels:

• Integrating the chain of effects from changes in atmospheric composition and climate to changes in biophysical systems to socioeconomic consequences (the "vertical" dimension)
• Including the interactions among systems, sectors, and activities (the "horizontal" dimension)
• Considering climate change in the context of other trends and changes in society (the "time" or "global change" dimension).

Some case study examples have been highlighted in the following chapters, but integrated assessment is in its infancy, and the development of new integrated scenarios of socioeconomic changes, emissions of greenhouse gases, and potential changes in climate was not possible in the time available for preparation of this report. This type of analysis is a priority for the IPCC, however; it currently is the focus of two related activities: a special report on emissions scenarios and a task group on climate scenarios for impact analysis. We expect that the Third Assessment Report (TAR) will be based on such an integrated set of scenarios.

The gaps and deficiencies revealed in this special report suggest some priority areas for further work to help policymakers in their difficult task. These needs include:

• Better baseline data, climate and socioeconomic
• Better scenarios, especially of precipitation, extreme events, sulfate aerosol effects, and regional-scale changes
• Better understanding of the ecological and physiological effects of increasing CO₂ concentrations, taking account of species competition and migrations, soil and nutrients, acclimation, partitioning between crop yields, roots, stems, and leaves
• Dynamic models of climate, biospheric processes, and socioeconomic factors to take account of the developing, time-varying nature of global change
• Impact assessments across a range of scenarios and assumptions to enable the assessment of risk-particularly in regions composed primarily of developing countries, where resources for research and assessment have been inadequate to date
• More and better integrated assessments across sectors, from climate change to economic or other costs, across countries and regions, including adaptations and other socioeconomic changes.

Clearly, impact assessments have not been made across all potentially affected sectors and regions, so many potential costs and benefits remain to be examined and, where possible, quantified. Nevertheless, we believe the present report summarizes a substantial body of work that, if carefully interpreted, may provide useful guidance to policymakers.