Evapotranspiration

Evapotranspiration (ET), which is one of the key elements in the hydrological cycle, refers to the process by which water is evaporated, encompassing evaporation from the soil or vegetation surface (including interception evaporation) and transpiration from plants. Elements influencing the rate of ET include the level of solar radiation, atmospheric vapour pressure, temperature, wind, soil moisture content and vegetation type. This process is responsible for a large part of the water loss from the soil during a crop’s growth cycle and is critical for understanding the state of water resources. This chapter presents anomalies of actual ET at the global scale for four seasons in 2022. The rates of actual ET are controlled by the amount of water that is available (which is dependent on the initial hydrological conditions in the basin) in addition to the meteorological forcing.

Sustainable Development Goals:

Clean Water and Sanitation

Climate Action