NASA came up with this number by using its Gravity Recovery and Climate Experiment satellites to eyeball the water storage in the Sacramento and San Joaquin river basins. This data showed that the water storage in these basins was 11 trillion gallons below normal seasonal levels at the peak of the drought earlier this year, according to the NASA announcement.
The volume of water in these basins has dropped by 4 trillion gallons each year since 2011, with most of this loss due to the lack of groundwater under the state’s Central Valley.
Now, you may have noticed that it has been raining a lot in California recently. (Perhaps you have been paying attention to the news, or maybe you live in California and you keep going outside without an umbrella because you’re just having that kind of week, and in between losing your keys and sitting on your glasses of course you went outside without an umbrella.)
As of last week, nearly 95 percent of California was experiencing drought that ranged from “severe” to “exceptional,” according to the U.S. Drought Monitor. The rain last week didn’t alter the Drought Monitor’s latest summary, though more rain could potentially alter the next report, the national summary said.
Still, the rain won’t be enough to make up for years of drought, NASA’s scientists say. “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,” Jay Famiglietti of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., said in a statement announcing the numbers.
If you happen to have 11 trillion gallons of water handy, please contact NASA.