
Retrieved from: Landscape resource
“For the first time, U.S. Geological Survey scientists have mapped long-term average evapotranspiration rates across the continental United States – a crucial tool for water managers and planners because of the huge role evapotranspiration plays in water availability.
“Why are evapotranspiration rates so important to know? It’s because the amount of water available for people and ecosystems is the amount of annual precipitation – that is, snow or rain – minus the amount of annual evapotranspiration. Evapotranspiration itself is the amount of water lost to the atmosphere from the ground surface. Much of this loss is the result of the “transpiration” of water by plants, which is the plant equivalent of breathing. Just as people release water vapor when they breathe, plants do too.
“Since evapotranspiration consumes more than half of the precipitation that happens every year, knowing the evapotranspiration rates in different regions of the country is a solid leap forward in enabling water managers and policy makers to know how much water is available for use in their specific region,” said Bill Werkheiser, associate director for water at the USGS. “Just as importantly,” he added, “this knowledge will help them better plan for the water availability challenges that will occur as our climate changes since transpiration rates vary widely depending on factors such as temperature, humidity, precipitation, soil type, and wind.”
Read more: Water online







Recent Comments