POTENTIAL IMPACTS OF CLIMATIC CHANGE ON THE PRODUCTIVE CAPACITY OF COSTA RICAN FORESTS:

Abstract

In the context of present-day scientific concern with predicted climatic changes resulting from the current untoward generation and release of CO2 and other "greenhouse" gases, the Department of Environmental Sciences of the University of Virginia (UV) is undertaking a study of the possible effects of global warming on the Earth's forests (for the U.S. Environmental Protection Agency Global Change Program: Forest). Much of the study involves computer (GIS) modelling of climatic/vegetation change scenarios on a global geographic scale. This study has the active collaboration of the International Institute for Environment and Development (IIED) and The Climatic Research Unit of the University of East Anglia (England) under a grant from the Swedish International Development Agency (SIDA). As an adjunct to the main UV study, larger-scale, regional and country level case studies have been included for corroboration and to facilitate analysis of the economic, social, and policy consequences of eventual global warming, should it occur. Costa Rica and Nicaragua have been selected for detailed analyses in the Tropical, Central American-Caribbean region. The Tropical Science Center, a not-for-profit Costa Rican research association was subcontracted by the University of Virginia to undertake detailed modelling and preliminary analyses of the implications of two potential climatic change scenarios on the forests of Costa Rica. Specifically, the Tropical Science Center was to: Develop manually-altered Life Zone maps of Costa Rica at a working scale of 1:200,000 for climatic change scenarios of 2.5 (Scenario 1) and 3.5 degrees Celsius (Scenario 2) increased mean annual air temperature. Both scenarios also assume a 10 percent increase over the present average annual precipitation. Both changes are assumed to occur progressively from the present with impact dates between the years 2060 and 2070. Undertake a hypothetical analysis of the possible gross implications of these changes to forest sector land use, with emphasis on production forests, firewood, and protected area vegetation cover; and, under a letter of agreement with IIED, the findings of (1) and (2) would be used to: Estimate the hypothetical economic effects of these climatic changes on forest productive capacity in the principal production forest areas of Costa Rica and evaluate these effects in relation to present and future forest management and public policy. The procedures, findings, and major implications of the Costa Rican component of the study follow in this report.