Spatiotemporal Assessment of the Intensity, Duration, Frequency and Magnitude of Drought Using remote sensing data

Drought is one of the most important natural disasters in the country, with devastating environmental and economic effects. Most drought studies have focused on drought severity, and other drought characteristics such as magnitude, duration, frequency and extent have not been studied.In this research, the capability of meteorological indices and remote sensing data are combined and used to study all drought characteristics such as severity, duration, magnitude and extent of drought in inland and coastal areas. For this purpose, the SPI index was calculated using TRMM satellite precipitation products and the results were compared with synoptic stations. The results showed that the correlation coefficient between the SPI calculated from the image and the station data was 0.94. Also, the correlation coefficient was more than 0.83 in all of the stations in the study area and the total MAE was 0.24. Then, using these data, the characteristics of intensity, duration, magnitude and frequency of drought in the study area were calculated. The results showed that it is possible to obtain the drought extent characteristic using satellite imagery that cannot be calculated by other methods. This shows that satellite imagery has been able to eliminate the lack of spatial details of the station data and provide a comprehensive view of the drought situation at the area.