introduction: drought is a natural and recurrent feature of climate. the characterizations of it may change under the effect of climate change in future periods. during the last few decades a number of different indices have been developed to quantify drought probabilities. droughts are caused by disruptions to an expected precipitation pattern and can be intensified by unusually high temperatu...

climate is a multivariate system. every change in every climate variable could result in different changes in climate. recently, experts have paid extensive attention to frequency distribution sequence of climate elements. accordingly, many different indices have been defined. precipitation extremes can exhibit the phase space of climate system. a technique that can be used to analyze climate p...

Abstract In this research, SPEI (standardized precipitation and evaporation index) was used as an alternative index to SPI to study drought in warm southern coastal regions of Iran. Drought has a multi-scale nature that can be analyzed in time scales via analysis of precipitation and temperature data. Therefore, data were colected from 105 synoptic stations in Iran in 2015; Respective stati...

Existing drought indices have been widely used to monitor meteorological drought and agricultural drought; however, few of them are focus on drought monitoring for grassland regions. This study presented a new drought index, the Grassland Drought Index (GDI), for monitoring drought conditions in global grassland regions. These regions are vital for the environment and human society but suscepti...