Evapotranspiration is a critical activity in Earth’s dynamic systems, influencing the movement of water and nutrients, influencing the water cycle, and giving critical information for farmers to efficiently manage irrigation and water supplies.
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Understanding Evapotranspiration
- Definition: Evapotranspiration is the transfer of water from terrestrial surfaces into the atmosphere, and it is an important component of the global water cycle.
- The water cycle and its relationship to evapotranspiration: Evapotranspiration combines evaporation (water loss from soil) and transpiration (water movement and loss by plants), both of which contribute to overall water movement in the water cycle.
- Definition of the term: Evapotranspiration is the upward flow of water through plants and its subsequent loss into the atmosphere from exposed plant portions.
Evapotranspiration Influencing Factors
- Rate of evapotranspiration: Solar radiation, day length, soil moisture levels, ambient temperature, wind conditions, and the amount of water vapour already existing in the air all influence the rate of evapotranspiration.
- The effect of insolation: The rate of evapotranspiration is directly affected by the intensity of solar radiation since it provides the energy required to evaporate water from terrestrial surfaces.
- The importance of day length: The length of the day, soil moisture content, ambient temperature, wind patterns, and air moisture content all influence the rate of evapotranspiration.
Evapotranspiration’s historical importance
- The term “evapotranspiration” has been in use for at least 86 years, and it was first published with a hyphenated form.
- Charles Warren Thornthwaite’s contribution in 1944: Thornthwaite, a climatologist from the United States, developed and popularised the word “evapotranspiration” in 1944.
- Relevance for farmers in predicting crop water needs: Even today, evapotranspiration is important for farmers who use it to predict the amount of water needed to efficiently irrigate their crops.
Source: https://www.thehindu.com/sci-tech/science/evapotranspiration-part-of-cycle-transmitting-water-into-atmosphere/article66930621.ece