The worst Californian drought in decades is at its peak, and according to NASA it's going to take much more than a few thunderstorms to fix the problem. Much, much more.
How much water exactly? According to data from NASA, 11 trillion gallons. That's how much water it would take to put the state's Sacramento and San Joaquin river basins back to normal seasonal levels. NASA scientists presented the findings at the American Geophysical Union meeting in San Francisco on Dec. 16.
The analysis is the first of its kind. Scientists used data from NASA's Gravity Recovery and Climate Experiment (GRACE) satellites to study the three-year Californian drought. Their findings show that the Sacramento and San Joaquin river basins lost about 4 trillion gallons of water each year, with much of the loss thanks to the depletion of groundwater underneath California's central valley. NASA says the estimated 11 trillion gallon water loss is more water than California's 38 million residents use each year around 1.5 times the size of all the water in the U.S.'s largest reservoir. The GRACE satellites launched in 2002 and have been collecting data ever since.
"Spaceborne and airborne measurements of Earth's changing shape, surface height and gravity field now allow us to measure and analyze key features of droughts better than ever before, including determining precisely when they begin and end and what their magnitude is at any moment in time," Jay Famiglietti, lead scientist on the study, says in a NASA press release. "That's an incredible advance and something that would be impossible using only ground-based observations."
While recent storms in the area have brought some relief, scientists say they aren't near enough. After all, we are talking about a loss of 11 trillion gallons.
"It takes years to get into a drought of this severity, and it will likely take many more big storms, and years, to crawl out of it," Famiglietti says.
Related studies also analyzed the amount of snowpack in California's Sierra Nevada range. Data shows it is only half of previous estimates. Less snow means less snow water, as well as contributing to climate warming by allowing more sunlight to hit and warm the ground. In other words, California could use a lot more water, frozen or not.
