Analysis of Hydrologic and Agricultural Droughts in Central Part of Iran

In this paper, a comprehensive statistical analysis of climatic and hydrologic data such as precipitation, temperature, and streamflow data is performed. Then an algorithm is developed to study the drought characteristics, such as duration and severity for a region. A large sequence of synthetic data is generated in order to develop the probability density function of drought characteristics for planning and water allocation purposes. A water balance model is also developed to estimate the hydrologic and agricultural parameters in order to calculate the expected precipitation for normal conditions. This information is needed to determine the soil moisture anomaly index Z and the Palmer Drought Severity Index. The proposed algorithm is applied to the Isfahan region in the central part of Iran. The drought cycles are determined and compared using different techniques. A planning horizon of 30 years is selected and the probable water shortages are determined. The results of the study show the significant value of the proposed methodology for drought studies in arid and semiarid regions with limited data availability.