Temporal Monitoring of Hydrological Droughts in Ardebil Province

Nowadays, with a growing population and the increasing trend of recent droughts, scientific attention to the mentioned drought phenomenon is inevitable. In this study the Stream flow Drought Index (SDI) was used for analyzing the hydrological droughts over the last three decades in the northwest of Iran (Ardebil province). The periods of 3, 6, 9, and 12 months and also 5 and 10 years were selected for the spatiotemporal monitoring of the hydrological droughts. The temporal drought analysis showed that the most of drought events over the reference periods have occurred in the last 15 years. In other words, there was an approximately normal status in the most of stations in the first study period of 15 years. The most severe hydrological droughts occurred in the Poleh Almas and Poleh Soltani on the Balokhlo-Chai and Khiav-Chai gauging stations, respectively, at the 3- and 6-month scales in 2010. The results revealed that the most severe hydrological drought periods occurred in 2010.