Untersuchung der Dürre und Nässe der Wetterstation Isfahan anhand des SPI-Index

Drought is one of the climatic phenomena that occurs in all climatic conditions and in all regions of the planet. Various indicators are used to quantify this phenomenon and evaluate it. The index used in this study to study drought and wet season is the standardized SPI precipitation index. For this purpose, monthly rainfall data for a statistical period of 29 years (1989- (1961) were studied with the aim of statistical analysis of rainfall and determination of dry and wet years. The results of this study show that the severity of drought in Isfahan province Mild droughts, that is, normal drought conditions, account for a larger share than other droughts, and in general, among all SPI conditional transmission modes, the transition from normal to drought is more likely than other modes .According to the SPI index, Isfahan province has experienced more drought events compared to wet season and its climate has a greater tendency to transition from normal to dry.