Satellite - Based Drought Assessment Using Vegetation Indices: NDVI, NDWI, and NDDI

Drought is a recurring climatic hazard that significantly impacts agriculture, ecosystems, and water resources. Timely mitigation and sustainable resource management depend on accurate drought assessment. This study highlights the use of satellite - based remote sensing techniques for drought monitoring through vegetation indices such as the Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), and Normalized Difference Drought Index (NDDI). A more comprehensive understanding of the geographical and temporal subtleties of drought conditions can be gained by integrating vegetation - sensitive indices, such as NDVI, NDWI, and the more sophisticated NDDI, rather than depending just on conventional ground - based techniques, which may be constrained in scope and timeliness. Red and near - infrared reflectance are used by NDVI to quantify vegetation health, red and short - wave infrared reflectance is used by NDWI to evaluate plant water stress, and NDDI combines the two indices to produce a more sensitive predictor of drought severity. These indices make it possible to analyze drought conditions on a broad scale, economically, and promptly, particularly in areas with inadequate ground - based data. In the face of growing climate unpredictability, the accuracy of drought detection is improved by combining remote sensing data with meteorological parameters, providing important information for agricultural planning and water resource management.