TY - JOUR ID - 61494 TI - Droughts analysis in the Northeast of Iran using Joint Deficit Index (JDI) JO - Iranian journal of Ecohydrology JA - IJE LA - en SN - 2423-6098 AU - Mirabbasi Najaf Abadi, Rasoul AU - Ahmadi, Farshad AU - Ashuri, Meisam AU - Nazeri Tahroudi, Mohammad AD - Assistant Professor, Water Engineering Department, Shahrekord University, Shahrekord, Iran AD - PhD Candidate of Water Resources Engineering, Shahid Chamran University, Ahvaz, Iran AD - MSc. Graduate, West Azarbaijan Regional Water Authority, Urmia, Iran AD - PhD Candidate of Water Resources Engineering, Birjand University, Birjand, Iran Y1 - 2017 PY - 2017 VL - 4 IS - 2 SP - 573 EP - 585 KW - Copula Functions KW - Drought KW - Joint Deficit Index KW - empirical copula DO - 10.22059/ije.2017.61494 N2 - Monitoring and prediction of droughts, especially accurate determination of its start time and duration, is very important in water resources management and planning drought mitigation strategies. In this study, drought conditions in the Northeast of Iran was evaluated by means of Joint Deficit Index (JDI). Monthly precipitation data from 6 synoptic stations including Torbat Heydariyeh, Sabzevar, Semnan, Shahroud, Gorgan and Mashhad during the period of 1971 to 2011 were used for calculating the JDI index. Results showed that in recent years the number of dry months across study area (especially at wet regions) increased, significantly. As in all of considered stations (except Semnan station), the percentage of dry months increased to over (more than) 50% over the past 10 years (2002-2011). Results showed that the JDI provides a comprehensive assessment of droughts and it is capable of reflecting both emerging and prolonged droughts in an accurate manner and allows for a month-by-month drought assessment. UR - https://ije.ut.ac.ir/article_61494.html L1 - https://ije.ut.ac.ir/article_61494_d38ca8eef59cafb36df3c1bffd85a0df.pdf ER -