The Historical Climate — Evapotranspiration indicator shows the historical trend of reference evapotranspiration (ET₀ FAO), calculated using the Penman-Monteith equation. It represents the amount of water transferred from the land surface to the atmosphere through soil evaporation and plant transpiration.
Evapotranspiration is a fundamental process in the hydrological cycle, influencing water resource management, weather forecasting, crop growth, and ecosystem energy balance. Rising ET₀ trends may indicate increasing water stress.
Data come from the Open-Meteo Historical Weather API. The variable used is et0_fao_evapotranspiration (daily FAO reference evapotranspiration). Data are interpolated to the site's geographic position.
| Code | Name | Provider | Type | Coverage | Availability |
|---|---|---|---|---|---|
WRD_OPNMT_99 | Open-Meteo Historical Weather | Open-Meteo | db | Global | 1940 - present |
Historical trend of reference evapotranspiration (ET₀ FAO Penman-Monteith). Open-Meteo variable: et0_fao_evapotranspiration. Source: Open-Meteo Historical Weather API. Unit: mm.