GIS-based multi-criteria approach for drought hazard modeling in the Ba river basin, Vietnam

Drought is a dangerous and expensive natural occurrence that slowly affects a country or region's ecology, economic, and social life. This paper aimed to delineate drought hazard zones in the Ba river basin, Vietnam, using the analytical hierarchy process (AHP) and geographical information system (GIS) technique. In this study, six thematic layers including rainfall, slope, land use, temperature, humidity, and drainage density were considered as prime criteria affecting drought occurrence. Weights were assigned to these six thematic maps depending on their significance. The acquired outcomes showed that the areas of the basin were facing various drought hazard levels including very low, low, moderate, high, and very high, each of which represents 1.36, 13.36, 39.2, 33.14, and 12.94% of the study area. The obtained findings were validated by comparing them to the results of the existing study and severe droughts that occurred in the past. The validation in this research confirmed the reliability and effectiveness of results achieved by AHP methods. The findings of the study contribute to enhancing drought preparation and resilience for communities at risk.