Assessing agricultural drought vulnerability: exploring historical drought hotspots in Indonesia through high-resolution satellite imagery

Abstract

Climate change is intensifying drought conditions globally, posing significant threats to agricultural production, food security, and rural livelihoods, especially in developing countries like Indonesia. This study provides a high-resolution assessment of agricultural drought vulnerability across Indonesia by integrating drought hazard and crop-yield risk indicators at a 1-km spatial resolution. For hazard assessment, the Standardized Precipitation and Evapotranspiration Index (SPEI) was calculated using ERA5-Land precipitation and evapotranspiration data from 2001 to 2021. Agricultural risk was assessed by developing a spatially detailed crop yield dataset on dry cropping season derived from MODIS-based vegetation indices (NDVI) and shortwave radiation data to estimate Net Primary Productivity (NPP). Yield anomalies, calculated by detrending the historical yield time series, served as indicators of drought-induced agricultural risk. By combining hazard and risk indicators, this research identified spatially explicit drought vulnerability hotspots across Indonesia, particularly highlighting intensified drought conditions in regions with major agricultural activities such as Java, South Sumatra, and South Sulawesi. The findings emphasize the importance of utilizing high-resolution satellite data for accurately identifying vulnerability hotspots, providing critical insights for targeted agricultural planning and drought adaptation strategies to support sustainable food production under increasing climatic uncertainty.