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url: https://www.eurocovers.eu/glossary/evapotranspiration
term: Evapotranspiration (ET)
definition: Combined evaporation from water and soil surfaces plus transpiration from plant material. Reference evapotranspiration (ET0) values are used for water management planning.
updated: 2026-05-25
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# Evapotranspiration (ET)

Combined evaporation from water and soil surfaces plus transpiration from plant material. Reference evapotranspiration (ET0) values are used for water management planning.

**Evapotranspiration (ET)** combines evaporation from water and soil surfaces with transpiration
from plant material. Reference evapotranspiration (ET0) — defined for a reference grass crop with
unlimited water — is used as a benchmark for irrigation planning and reservoir capacity design.
Reference values across the EU range from 600 mm/year in northern regions to 1,800+ mm/year in
southern Spain and Italy. Open industrial water bodies typically experience pan evaporation rates
1.0–1.4× ET0 in the same climate.