Spatiotemporal Analysis of Drought Severity in the Future under Climate Change Scenarios of CGCM3 in the Province of Isfahan

According to the Hadley center for climate prediction and research, it has been predicted that the severe and extensive droughts threaten the lives of millions of people on the earth due to the global warming in 21st century. Since the drought affects different activities like water resources, agriculture, economy, industry, and health, so investigation and evaluation of this disaster in the future is necessary for planning to cope with its impacts in different parts of the society. The purpose of this research is to compare the intensity of droughts under future climate conditions with current climate in the selected stations of the Isfahan province. For fulfilling this aim, at first, precipitation data for future periods in the selected stations of the Isfahan province were downscaled using change factor technique under scenario A2 of CGCM3. In the next step, the Standardized Precipitation Index (SPI) in two time scales of 3and6 months were estimated for four periods including 1971 2000(base period), 2011-2040, 2041-2070, 2071-2100 (for future periods). Severity of droughts in the base period and the future periods were extracted. The ratio of droughts severity in the future periods to the base period for different return periods were calculated in all stations. Finally, these ratios were interpolated by using the squared inverse distance method on the Isfahan province. Results showed that the ratio of drought severity in the future periods in comparison to the current climate will decrease at different return periods.