Assessing the drought extent using multiple indices of LANDSAT data -Case study of Coimbatore District

Coimbatore, a significant industrial and agricultural centre in Tamil Nadu, has experienced drought-related problems over the last 15 years, which have been made worse by climate change. Using Landsat satellite data, this study performs a spatial-temporal analysis of the drought in Coimbatore from 2010 to 2024 to evaluate changes in the frequency, length and intensity of drought occurrences. The vegetation health index (VHI) was developed to track drought conditions by evaluating data on land surface temperature (LST) and normalized difference vegetation index (NDVI). The results underscore the worsening drought conditions by showing a significant loss in vegetation health and an increase in land surface temperatures across the research period. The VHI demonstrated efficacy in monitoring the onset and intensity of drought, providing insightful information for regional water management, agricultural planning and climate adaptation strategies. This research underscores the importance of remote sensing in understanding and mitigating the impacts of drought in vulnerable regions like Coimbatore.