عنوان مقاله [English]
In this study, in order to determine the drought trend and calculate the reliable precipitation in Khuzestan, the data of annual precipitation of 11 stations in the province during the period of 25 years (2017-1993) was selected. In the next step, SPSS software was used to determine the statistical characteristics of precipitation stations (mean, geometric mean, standard deviation, coefficient of drought and drought variation of triple indices (DRI, PNPI, ZSIAP) for all stations. Then, based on the rainfall thresholds, the yearly, dry, normal, and wetting periods of the stations were calculated for each of the indices. The results showed that, comparing the corresponding computational values of the mentioned indices, the standardized precipitation index (ZSIAP) was more appropriately identified with greater reliability and reliability. Studies have revealed that, since 2007 and the entry into the final decade of the statistical period, not only the severity and frequency of droughts has increased, but also the multiplicity and diversity of drought stations have increased, so that most stations, especially the southwest, have more droughts have experienced. Drought regression using the Man-Kendall test showed that during the study period, Bostan, Behbahan, Shooshtar and Dezful stations have not been trendy. Omidieh, Izeh, Masjed Soleiman, Mahshahr, Abadan, Ramhormoz, Ahwaz have had a negative trend - the severity of droughts in these areas has increased.