Meteorological Drought Analysis for Helmand River Basin, Afghanistan

This study evaluates drought at Lashkargah, Farah, Adraskan, and Gardandiwal stations in Helmand River Basin (HRB) Afghanistan to determine appropriate indices for the basin. Thirty seven years of monthly recorded precipitation data from 1979 2015 are employed with different index (DI) methods which include Standardized Precipitation Index (Normal-SPI, Log-SPI, Gamma-SPI), Percent Normal (PN), Deciles. All applied annual long term data. The log-SPI gamma-SPI predict extreme conditions, whereas, normal-SPI determines wet less dry conditions. results emphasize that PN Deciles more comparison SPI methods. method shows longer period severe than other five indicate various intensities 1985, 1987, 1994, 1997, 1999, 2000, 2001, 2002, 2003, 2004 all stations. condition 2001 confirms reports same region. It is noted since capture historical periods successfully, these recommended as monitoring Basin.