Evapotranspiration

Combined surface water flux from soil/open-water evaporation plus plant transpiration. Distinct from the GCOS `evaporation-from-land` parent, which formally names the abiotic component — operationally most satellite ET products report the combined quantity, because the biotic plant-mediated component dominates over vegetated land and cannot be separated from evaporation by remote sensing alone. Canonical mass flux is kg m-2 s-1; commonly expressed equivalently as mm/day of water depth (1 mm/day ≡ 1 kg m-2 day-1). Flagship products are Penman-Monteith / Priestley-Taylor models driven by satellite inputs: MOD16A2 (MODIS 500 m 8-day, NASA LP DAAC), PML-V2 (Penman-Monteith- Leuning, CSIRO/PML, 500 m 8-day), ECOSTRESS L3/L4 (ISS 70 m, sparse overpass), GLEAM (0.25° daily). Consumed by agriculture/irrigation, drought-monitoring, water-budget, and hydrological-model ops.