How does this relate to agriculture?
|Image from Bridget Lassiter|
If you can predict evapotranspiration rates, you will be able to estimate the water demands of the crop. This may help you to determine whether or not to irrigate, for example. If crops do not receive enough water, their leaves may curl and their production decline as the plants fight to conserve what water they can. Knowledge of predicted temperature and wind conditions from weather forecasts can give you a clue to how strong the evapotranspiration rates will be.
Evaporation may also directly affect soil moisture conditions. If there is too much moisture in the soil, the farm machinery can get bogged down because it has to work too hard. The weight of the machinery can also compact the wet soil, leading to lack of air for healthy root systems to develop. If the soil is too dry, however, the plants may be easily stressed due to the lack of available water and a crust may sometimes form on top of the soil. This crust may be so impermeable that when it rains on top of the crusty soil, the rain runs right off rather than soaking in.