Evapotranspiration (ET)

The combined water leaving the land as evaporation from soil plus transpiration from plants. ECOSTRESS’s thermal data is a primary way to map it.

Why it matters

ET is how much water crops and ecosystems are actually using — the key signal for irrigation efficiency, drought stress, and the land-water budget.

In plain terms

The land “sweating”: water lifting off soil and breathing out of leaves. More ET means thirstier, more active vegetation.