Spatiotemporal Extent of Agricultural Drought Over Western Part of West Bengal

Climate variability has severe consequences on agricultural productivity. Studies related to drought monitoring using point data has not been widely successful. Remote sensing and GIS has proved to be a better alternative toward fast, accurate, and repetitive appraisal. This study focuses on the application of remote sensing and GIS for monitoring the spatiotemporal extent of agricultural drought over West Bengal, especially its western districts. Over the years, a large number of band rationing techniques and indices have evolved for assessment of crop condition, of which VCI (vegetation condition index) derived from NOAA-STAR has been used for this particular study. This vegetation index values were then compared with CHIRPS rainfall data based RAI (rainfall anomaly index) to identify impact of deficit rainfall on vegetation condition. This provided a better understanding for identifying the drought. Yield anomaly index (YAI) were also computed with the help of crop production data collected from district statistical handbooks in order to estimate the reduction in crop production as a result of drought. Using these indices, it was evident that during the study period of 1997–2017, the years 2000–2001 and 2010–2011 had experienced severe drought.