This Snap-On Sensor Could Tell Farmers Exactly How Much To Water Their Crops
On October 13, 2017
In 2010, scientists at California’s Pacific Institute, a global water think tank, defined a condition Earth could face called “peak water.” Loosely, it’s analogous to peak oil, but it’s not just that we’ll run out of water. Fresh water won’t vanish, but it will become still more unevenly distributed, increasingly expensive, and harder to access. Many parts of the world are facing water stress, and 80 percent of the fresh water that gets used around the world gets used for irrigating crops, according to the Pacific Institute’s president emeritus Peter Gleick.
Over the past 40 years or so, total water use in the United States began to level off. Part of that is due to greatly improved irrigation, and part of that is due to remote sensing technologies—satellites, radar and drones—that assess water stress in fields based on temperature or how much light the canopy reflected in different wavelengths. The better we can track hydration in plants, the more we can avoid both over- and under-watering our crops. But while these methods are suited well to broad views and can give an overall picture of the water fields are using, a team from Penn State University has been exploring a much more detailed method of measuring water stress, plant by plant