Seasonal drought assessment using the Normalized Difference Drought Index (NDDI) in Satara District of Western Maharashtra (2014-2023)

Abstract

This study investigates the spatio-temporal variability of drought in Satara district of Western Maharashtra from 2014 to 2023 using the Normalized Difference Drought Index (NDDI), derived from Landsat-8 satellite data. Seasonal drought conditions were assessed for rabi, summer, and kharif seasons, along with drought-rainfall relationships. Results showed substantial seasonal variations, with summer consistently exhibiting the highest drought severity due to elevated temperatures and minimal precipitation. Kharif season showed the least drought impact as a consequence of monsoonal rainfall and improved vegetation cover. Rabi season displayed moderate drought stress influenced by limited residual soil moisture. The correlation analysis confirmed a strong negative relationship between rainfall and NDDI during kharif (r = −0.70), moderate during summer (r = −0.56), and weak during rabi (r = −0.21). Spatial analysis identified persistent drought hotspots in the eastern region of Satara, particularly Man, Khatav, Phaltan, and Khandala. The findings demonstrate the usefulness of NDDI as a remote-sensing-based agricultural drought monitoring tool and provide guidance for sustainable water resource planning and climate-smart agricultural management in drought-prone areas.