Assessment of future drought under climate change status, case study: Eskandari Basin, Isfahan Province

Studies of climate change and its impacts on the frequency and intensity of future droughts can help programming for the management of water resource and adaptation of the destructive effects of this phenomenon. The aim of this research is trying to assess the climate change in 2011-2030 period and its impact on drought in Eskandari Basin. To achieve this purpose, after validating Lars-WG to generate weather parameters, HadCM3 output downscaled under A2 and B1 scenarios. Next, minimum and maximum temperature and precipitation was predicted. Also, SPI index was calculated. Underlying these scenarios minimum temperature growth dramatically in March, June, July and September 0.3 to 1.6 °C. Additionally, highest and lowest increment in maximum temperature will occur about 0.02 and 1.6 in May and April, respectively. However, the results indicated an increase of 7.2 to 10.9 percent in the average of annual precipitation, but due to the fact that there is no any increase in the number of wet days, extreme rainfall intensity will soar remarkably. Substantial reduction in precipitation belongs to May and April. Regarding this issue, this shortage will affect with several months lag and the most severe agricultural drought will occur in August and hydrological drought will fall out in December based on six and 12 months SPI, respectively. Annual analysis showed that 75 percent of the years are in normal condition. Therefore, in Eskandari Basin, increasing drought frequency will not be expected in 2020s. But, precipitation oriented towards warm seasons.