Evaluation of Drought in Gandaki River Basin of Nepal

Drought is often considered a silent disaster, leading to food and water shortages, displacement, and even conflict. Although evidence of ongoing climate change has been observed, limited research is carried out on drought conditions in Gandaki River Basin of Nepal. This study analyzed four indices i.e., Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Land Surface Temperature (LST) and Normalized Difference Drought Index (NDDI) for January and November between ۱۹۹۱ and ۲۰۲۱ by using Geographic Information System (GIS) and remote sensed data. NDVI showed that dense vegetation decreased by ۹۳.۲۶% and built-up area increased by ۹۶.۸۸% in January compared between ۱۹۹۱ and ۲۰۲۱. Compared between ۱۹۹۱ and ۲۰۲۱, NDWI showed that the high water stressed area increased by ۴۹.۵% in January. NDDI showed increased in abnormally drought area in January (۱۶۴.۰۳%) compared between ۱۹۹۱ and ۲۰۲۱.Both climate change and human activities significantly contributes increasing trend of drought over the ۳۰-year period in Gandaki River Basin. The study suggests exploring the potential of modern tools such as GIS and Remote Sensing for prediction of drought and monitoring its impact on ecosystems and human. This will be beneficial for policy makers for developing the strategy for combating drought and climate change.

Evaluation of Drought in Gandaki River Basin of Nepal Keywords:

Climate change , NDVI , NDWI , NDDI , LST