Spatiotemporal variation of projected drought characteristics in Iran under climate change scenarios using CMIP5-CORDEX product

Abstract

This study aims to assess the change of drought characteristics (intensity, duration, and frequency) under the effect of climate change in Iran using the modified standardized precipitation index (MSPI) and theory of runs on annual and seasonal scales for three near-future, mid-future (MF), and far-future climates. Hence, regional climate models extracted from South Asia-Coordinated Regional Climate Downscaling Experiments (CORDEX-SA) are applied. Regarding the result, MSPI could assign the standardized precipitation index (SPI) values better than the conventional form of SPI during the historical period (HP). The outcomes revealed that the northeast stations will experience a decrease in intensity (up to 24.57% in MF compared to HP) until 2100 at seasonal timescale. While the duration and frequency of drought will be increased. Although the greatest increase in intensity changes of droughts (up to 91%) until the end of the century will happen in the eastern and southwestern regions of Iran, these regions will face the maximum decrease in the duration (−30.54%) and frequency (−25%) of droughts compared to HP at seasonal timescale. In addition, regarding the outcomes of this study, strategies can be adopted to better manage water resources for various regions of Iran.