Jalal Behzadi, Z. Jafarpour and P. Kardovani
Abstract
Increase of population and consequently increase of requirement for water and food has increased the damage of drought. Drought is a repeated continental disaster that is dependant on precipitation and deferment of precipitation season. In this study, severity, abundance and extent of drought in Guilan in north of Iran during 30 years statistical period from 1967 to 2005 has been studied using 3 drought indices: Standardized Precipitation Index (SPI), Deciles Index (DI), and Difference of precipitation percentage method. Results showed that although Guilan is in a pluvial area with annual precipitation of 1070 mm, but drought is not only rare, but also a repeatable phenomenon. All 3 methods used in this study showed severe drought in 1979, 1991, and 1995; furthermore risk of drought is higher in middle parts of province, therefore it requires more attention in water sources management.