Evaluation of geostatistical methods in hydrological drought severity zoning in the Malayer plain

Due to the undeniable impact of drought on human life, careful study of this phenomenon seems essential. The purpose of this study is to evaluate the accuracy of Geostatistical methods in preparing the drought severity map in the Malayer plain using the Standardized Water-Level Index (SWI) and analyze the trend of the Piezometric well. The results based on RMSE and MAE criteria showed that among the interpolation methods, simple Kriging method (SK) with the spherical model due to having lower RMSE and MAE (for 1999 with RMSE = 0.05 and MAE = 0.001 and For 2012, with RMSE = 1.04 and MAE = - 0.0004) was the most accurate method and was selected as the most appropriate approach to prepare the drought severity map. The results also showed that in most Piezometric wells in the region, the trend of water table level drop is significant.