Penman calculation of evaporation

Earth science

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July 1, 2026

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The Penman calculation is a method used in Earth science to estimate evaporation, a key component of the water cycle. Evaporation is the process where liquid water turns into a gaseous state and returns to the atmosphere, replenishing air humidity. This rate is influenced by factors such as surface characteristics, water availability, and atmospheric conditions like humidity, wind speed, radiation, and temperature. The Penman equation specifically considers these elements to determine potential evaporation, essentially the maximum possible rate of water loss under given meteorological conditions. This calculation is crucial for understanding water balance in catchments and managing resources like irrigation.12

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climate
Evaporation and humidity
…fact, according to the well-known Penman calculation of evaporation (an equation that considers potential evaporation as a function of humidity, wind speed, radiation, and temperature), this loss of water is essentially determined by the net radiation balance during the day.
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…fact, according to the well-known Penman calculation of evaporation (an equation that considers potential evaporation as a function of humidity, wind speed, radiation, and temperature), this loss of water is essentially determined by the net radiation balance during the day.
Read More