Global Daily Grass Reference Evapotranspiration (ETo) Climatology (1981–2010) Derived from Integrated Multi‑Source Data

This dataset provides a globally consistent daily climatology of grass reference evapotranspiration (ETo, units in millimeter) for the 1981–2010 climatological period. The product integrates multiple sources to improve spatial completeness and regional accuracy, including TerraClimate monthly potential evapotranspiration (PET) fields, the Australian Bureau of Meteorology evapotranspiration climatology, and targeted corrections for known anomalies such as the Caspian Sea interior. Source datasets were harmonized to a common spatial framework, merged to produce a unified global reference evapotranspiration surface, and temporally disaggregated from monthly to dekadal and ultimately to daily resolution. Daily fields were derived using relationships informed by Hobbins' global daily reference ET dataset (https://doi.org/10.5066/P9IIQMV1) to ensure physically consistent temporal patterns. The resulting dataset provides a continuous, gap‑free global daily reference ET climatology gridded surface product.