Abstract
Drought monitoring on small islands is challenged by coastline-grid mismatch and by the possibility that meteorological recovery precedes recovery of soil-water conditions. This study presents a native-grid, area-weighted framework for the Ionian Islands using Climate Hazards Center Infrared Precipitation with Stations version 3 (CHIRPS v3), TerraClimate potential evapotranspiration, and modelled soil-water storage for 1981–2024. The framework preserves each product’s original spatial support, derives monthly island series, calculates the Standardized Precipitation Evapotranspiration Index (SPEI) at 1-, 3-, 6-, and 12-month scales, constructs a drought-event catalogue, evaluates temporal trends, and quantifies soil-water recovery. It identified 690 scale-specific events; longer accumulation scales produced fewer but more persistent events. No generalized robust intensification was detected. Full-period negative SPEI-3 signals in Kefalonia and Ithaca were sensitive to the 2020–2024 terminal period, while the remaining island trends were not significant after false discovery rate adjustment. In 34.3% of completed events, modelled soil-water storage remained below normal when SPEI first returned to nonnegative values. Recovery lags had a median of 0 months, a 90th percentile of 4 months, and a maximum of 20 months. The framework provides a transparent, transferable basis for drought monitoring and water-resource planning in insular environments.