drought detecting is a necessary aspect of drought risk management. it is generally performed usingdifferent drought indices that are effectively continuous functions of rainfall and other hydro- meteorologicalvariables. a number of drought indices have been introduced and used in various countries to date. in thecurrent research, four meteorological drought indices including the standardized p...

Accurate and reliable drought monitoring is essential to drought mitigation efforts and reduction of social vulnerability. A variety of indices, such as the standardized precipitation index (SPI), are used for drought monitoring based on different indicator variables. Because of the complexity of drought phenomena in their causation and impact, droughtmonitoring based on a single variable may b...

[Drought indicators are proliferating, but with little consideration of which are most meaningful for describing drought impacts. A number of recent reviews compare different drought indicators, but none assess which indicators are actually used in the many operational drought monitoring and early warning efforts, why they were selected, or whether they have been ‘ground-truthed’, i.e., compare...

the impact of meteorological and hydrological drought on groundwater resources in coastal deserts in the south of iran was investigated during 1991-2011, using standardized precipitation index (spi), standardized runoff index (sri), and groundwater resources index (gri). the results indicated that wet and drought spells governed the area in the first and second decades, respectively, which was ...

In recent decades, various kinds of remote sensing-based drought indexes have been proposed and widely used in the field of drought monitoring. However, the drought-related software and platform development lag behind the theoretical research. The current drought monitoring systems focus mainly on information management and publishing, and cannot implement professional drought monitoring or par...

Attributed to climatic change and uncertainty of weather conditions, drought has become a recurrent phenomenon. It is manifested by erratic and uncertain rainfall distribution in rainfall dependent farming areas. The hitherto methods of monitoring drought employed conventional methods that rely on availability of metrological data. The objectives of this research were to: 1) identify the critic...

Each year, droughts cause significant economic and agricultural losses across the world. The early warning and onset detection of drought is of particular importance for effective agriculture and water resource management. Previous studies show that the Standard Precipitation Index (SPI), a measure of precipitation deficit, detects drought onset earlier than other indicators. Here we show that ...

Drought is a normal part of climate and occurs in virtually all regions of the world. Recent droughts have illustrated the vulnerability of all parts of the United States to extended periods of precipitation deficiency. Drought preparedness planning has become a widely accepted tool for governments at all levels to apply to reduce the risks to future events. In the United States, planning has b...

drought is a major environmental disaster in many parts of the world. knowledge about the timing, severity and extentof drought can aid planning and decision-making. drought indices derived from in-situ meteorological data have coarsespatial and temporal resolutions, thus, obtaining a real-time drought condition over a large area is difficult. this studyused advanced very high resolution radiom...