SPEI

This dataset provides a monthly 6-month Standardized Precipitation Evapotranspiration Index (SPEI-6) reconstruction for Central America (Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama), covering January 1981 to December 2025 at ~5.5 km resolution. SPEI-6 was calculated from CHIRPS v2.0 monthly precipitation and ERA5-Land-derived reference evapotranspiration (Penman-Monteith method), following the standard SPEI methodology (climatic water balance aggregated over a 6-month rolling window, fitted to a log-logistic distribution). The dataset was developed to characterize ENSO-driven drought dynamics across the Central American Dry Corridor and supports the analysis presented in Reygadas & Quesada-Román, "ENSO-driven drought across Central America: Vegetation responses and land-use & land-cover sensitivity" (in review). Data are provided as a compressed multiband GeoTIFF, one band per month (540 bands total), in WGS84 (EPSG:4326).