18. Assessment of Drought Using Multi-parameter Indices

A drought is a condition of a drier period that prevails over an area when normal rainfall decreases for weeks, months or even years. Its consequences mainly include water-related issues which seem to come then we can understand about this climate-induced hazard. The present study has shown that the Shilabati river catchment is located in one of the driest regions of West Bengal. Here the drought risk zone has been assessed using Landsat 8 OLI images by calculating Standardized Precipitation Index, Normalized Difference Moisture Index, Land Surface Temperature and Normalized Difference Vegetation Index, Normalized Difference Water Index and groundwater level. These indices are useful for recognition and monitoring drought in a larger area at different time series. In this study mainly NDVI and NDMI indicate agricultural drought, the metrological drought is specified by SPI and the hydrological drought is designated by NDVI and well depth. Correlation and regression studies have been performed between NDVI, NDWI and NDMI and as a result these are accepted for understanding drought scenario. The results of SPI, LST and different groundwater level scenario also helped to identify the risk-prone zone.