California's Greatest Water Gain for Decades Seen in Satellite Images

California has seen a huge amount of water returned to its drought-hit soils because of intense storms and huge snowmelt since the beginning of 2023.

Data from the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) satellite mission, a partnership between NASA and the German Research Centre for Geosciences (GFZ), shows that California has just seen its greatest year-over-year water gains for two decades.

GRACE-FO found that the water contained in lakes, rivers, soil, snowpack and underground aquifers in California's Central Valley rose by around 20 inches between October 2022 and March 2023. The average increase during the same period is normally only around half that amount.

NASA maps show the results of this deluge of water, revealing how in October 2022, much of the Central Valley was parched in October. As of March, it had above average amounts of water—with blue colors on the maps showing areas wetter than average relative to 2004–2010, and red colors representing an area being drier than average.

This water has served to pull the state out of its intense drought conditions.

U.S. Drought Monitor data showed that on September 27 2022, the entire state was in some form of drought condition, with 0.24 percent in "abnormally dry" conditions, 5.75 percent in "moderate drought," 53.11 percent in "severe drought," 24.34 percent in "extreme drought," and 16.57 percent in "exceptional drought."

By March 3, this had shifted significantly, with 26.84 percent of the state being drought-free, 30.10 percent "abnormally dry," 24.06 percent in "moderate drought," and 19.00 percent in "severe drought," with no areas in the more intense categories.

As of June 6, 70.88 percent of the state was drought-free, with only 4.63 percent in "moderate drought," and none in more severe conditions.

The water influx from rains and snowmelt has helped to refill some of the dwindling reservoirs and lakes across California. Lake Shasta reached nearly full capacity in May for the first time in four years, while Lake Oroville is now 97 percent full.

It has also caused major flooding in some areas, with Yosemite National Park being inundated with meltwater. Previously dried lakes have rapidly burst their banks, with Tulare Lake growing to nearly the size of Lake Tahoe.

Despite the positive impact of this water on California's drought-ridden environment, it won't be enough to fully pull the state out of drought.

"This will definitely help drought conditions in the short run. In the long run we still face risks associated with higher temperatures due to climate change," Tom Corringham, a research economist at the Scripps Institution of Oceanography in San Diego, previously told Newsweek.

"Some areas will get wetter and some will get drier. In all areas we expect more precipitation to fall as rain than as snow, which makes capturing and storing the water more challenging," he said. "Similarly, we expect precipitation to be more concentrated in the winter months, with less rain in spring and fall, and more rain falling in intense atmospheric river storms. This makes water management more challenging."

Atmospheric rivers are storms akin to rivers in the sky that dump massive amounts of rain and can cause flooding, trigger mudslides and result in loss of life and enormous property damage, according to Reuters.

The effects of climate change are likely to make it harder for California to recover all of its lost water, and make it more difficult to predict future weather patterns.

"In an ideal world we'd have consistent year-to-year precipitation and consistently ample snowpack in the Sierra and the Rockies, but climate change is making the system more volatile and increasingly difficult to manage," Corringham said.

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