Satellite imagery sheds light on agricultural water use
21 April 2018
Earth may be the "Blue Planet", with more than 70 percent of its surface covered in water, but it is still a thirsty planet, with freshwater in heavy demand. The most significant draw on the water supply is crop irrigation, accounting by some measures for nearly two-thirds of U.S. surface-freshwater withdrawals.
Keeping track of just how much water gets used—and making sure it gets used efficiently and legally, where and when it's needed—across millions of acres of crop land is no easy task.
Researchers armed with data from the Landsat Earth-observing satellites recently teamed up with Google to make it a whole lot easier. The researchers from the University of Idaho, the University of Nebraska, and the Desert Research Institute are using the satellite images to map evapotranspiration—water evaporating from the ground or transpiring from the plants.
Image credit: Google Earth / EEFlux - Map of an agricultural region in California, dark blue and dark green represent higher levels of evapotranspiration, while light brown represents low levels.