Impacts of climate and land-cover changes in arid lands of Central Asia

摘要

Despite the growing understanding of the global climate change, great uncertainties exist in the prediction of responses of arid regions to global and regional, natural and human-induced climate change. Meteorological data series show a steady increase of annual and winter temperatures in Central Asia since the beginning of the 20th century that might have a strong potential impact on the region's natural ecosystems, agricultural crops, and human health. Analyses of the NOAA AVHRR temporal series since the 1980s showed a decrease in aridity from 1991-2000 compared to 1982-1990. While most climate models agree that the temperature in arid Central Asia will increase by 1-2℃ by 2030-2050, precipitation projections vary from one model to another and projected changes in the aridity index for different model runs show no consistent trend for this region. Local and regional human impacts in arid zones can significantly modify surface albedo, as well as water exchange and nutrient cycles that could have impacts on the climatic system both at the regional and global scales.