Assessing Drought Risk and the Influence of Climate Projections in Sri Lanka for Sustainable Drought Mitigation via Geospatial Techniques

Abstract

Sri Lanka is highly vulnerable to climatic change, making drought risk assessment an essential tool for the development of effective mitigation strategies. This study addresses existing gaps by employing geospatial techniques to evaluate drought risk in Sri Lanka and focusing on future trends in temperature and precipitation. The observed meteorological data, projected climate variables, and environmental factors were analyzed using the standardized precipitation evapotranspiration index (SPEI). Key findings show that the northwestern and southern regions of Sri Lanka are particularly susceptible to increased drought hazards, while the southwestern region, characterized by the highest density of built-up areas, is also more vulnerable. A combination of hazard and vulnerability data reveals that the northwestern, upper–central, and southern regions exhibit relatively high drought risk. The spatial distributions of the predicted meteorological variables align closely with current patterns, and significant increasing trends were observed under the SSP 2.6 and SSP 8.5 scenarios. Precipitation and temperature correlate with drought, indicating an elevated risk of future drought events. This study provides a comprehensive understanding of the interplay between climate change and drought risk in Sri Lanka, offering valuable insights for policymakers and resource managers to develop sustainable drought mitigation plans.