According to data obtained from the GRACE-FO satellite mission, a joint effort by NASA and the German Research Centre for Geosciences (GFZ), California experienced a significant increase in water levels within the San Joaquin, Sacramento, and Tulare river basins (highlighted in yellow) from October 2022 to March 2023. This substantial gain encompasses various water sources such as lakes, rivers, reservoirs, snowpack, and groundwater aquifers. Credit: NASA’s Scientific Visualization Studio
After enduring years of severe drought and dwindling groundwater supplies, California has now witnessed its most substantial year-over-year surge in water levels in the past two decades. The recent winter season brought forth an abundance of atmospheric rivers, which alleviated a portion of the water deficit accumulated during the state’s ten-year period of drought, including the three driest years ever recorded in California.
The animation depicts the changes in the overall water volume in the California region, encompassing the Sacramento, San Joaquin, and Tulare river basins, from 2002 to 2023. The zero line on the graph represents the average water volume in the region between 2004 and 2010. Credit: NASA’s Scientific Visualization Studio
Visualize the Central Valley region of the state (outlined in yellow above) as an enormous swimming pool. The measurements obtained from GRACE-FO account for all the water contained within the lakes, rivers, soil, snowpack, and underground aquifers in that particular area. Over the period from October 2022 to March 2023, the storms supplied sufficient water to raise the water level within this “swimming pool” by approximately 20 inches (about 500 millimeters). This increase is approximately twice the average winter water gain since the commencement of satellite-based water storage measurements in 2002 with the first GRACE mission.
While surface water basins are replenishing, it may take several years for the underground freshwater stores (aquifers) utilized for irrigation and other purposes to fully recharge. Felix Landerer, the GRACE-FO project scientist at NASA’s Jet Propulsion Laboratory in Southern California, stated, “A single favorable winter of precipitation cannot compensate for years of extreme drought and extensive groundwater usage.” The GRACE-FO team will continue to monitor the evolution of California’s water storage throughout the summer, as the snowpack melts and water levels in the state’s lakes, rivers, and reservoirs recede during drier weather conditions.
The line graph exhibits the seasonal fluctuations in the total water volume contained in California’s lakes, rivers, reservoirs, snowpack, and groundwater from 2002 to 2023. (The data gap from late 2017 to early 2018 corresponds to the decommissioning of the GRACE mission and the launch of its successor, GRACE-FO.) Credit: NASA’s Scientific Visualization Studio
These observations became possible due to the unique sensing methodology employed by both GRACE missions. As water shifts in the form of ocean currents, precipitation, groundwater movement, ice, and other factors, it causes subtle alterations in the planet’s mass near the surface, thereby slightly changing Earth’s gravitational pull. GRACE-FO precisely measures these minute changes, allowing researchers to estimate variations in the overall water volume within a given area.
Similar to its predecessor, the GRACE-FO mission comprises two identical satellites flying in tandem. As the leading satellite passes over an area with a greater mass, such as a region containing more water compared to another, the slight change in gravity propels it forward, resulting in an increased distance between the two satellites. Microwave and laser instruments onboard the spacecraft accurately measure the minute distance changes, thereby revealing valuable insights about the total mass of water responsible for those alterations.
Illustration of GRACE-FO in orbit. Credit: NASA/JPL-Caltech
Additional Information about the Mission:
The GRACE mission (2002-2017) was a collaborative venture between NASA and the German Aerospace Center, Deutsches Zentrum für Luft- und Raumfahrt (DLR). JPL managed the GRACE mission and currently oversees the GRACE-FO mission for NASA’s Earth Science Division within the Science Mission Directorate in Washington. GRACE-FO represents a collaboration between NASA and GFZ, while Caltech in Pasadena, California, manages JPL for NASA.
Table of Contents
Frequently Asked Questions (FAQs) about record-breaking water gains
What is the GRACE-FO satellite mission?
The GRACE-FO (Gravity Recovery and Climate Experiment Follow-On) satellite mission is a collaborative effort between NASA and the German Research Centre for Geosciences (GFZ). It involves two identical satellites that measure changes in the Earth’s gravitational pull to estimate variations in the total volume of water in a specific area. This data helps researchers track water storage, monitor droughts, and understand climate patterns.
How did the recent winter storms impact California’s water situation?
The recent winter storms brought a significant increase in water levels to California. These storms, known as atmospheric rivers, contributed to record-breaking water gains in the San Joaquin, Sacramento, and Tulare river basins. The added water helped alleviate some of the water deficit caused by the state’s prolonged drought period, providing relief to surface water basins and other sources like lakes, rivers, and reservoirs.
Can these water gains completely reverse the effects of the long drought in California?
While the substantial water gains are promising, they cannot entirely reverse the effects of the prolonged drought in California. The state’s groundwater levels, which are essential for irrigation and other needs, still suffer from years of extreme drought and extensive use. Replenishing underground aquifers may take several years, and it requires sustained precipitation and careful water management to fully recover from the long-term impacts of the drought.
How does the GRACE-FO mission measure changes in water volume?
The GRACE-FO satellites utilize a unique sensing approach to measure changes in water volume. As water moves within the Earth’s system, it causes slight alterations in the planet’s mass near the surface, resulting in changes in the gravitational pull. GRACE-FO precisely measures these minute gravitational changes by tracking the distance between the two satellites as they orbit the Earth. These measurements provide valuable insights into variations in water storage across different regions.
What is the significance of the record-breaking water gains for California?
The record-breaking water gains in California are significant as they indicate a positive shift in the state’s water situation. The increased water levels in surface water basins, rivers, reservoirs, and snowpack help replenish water resources and provide temporary relief to the drought-stricken regions. However, it is essential to maintain sustainable water management practices and continue monitoring the water storage evolution to ensure long-term water security in the state.
More about record-breaking water gains
- NASA GRACE-FO Mission
- GRACE-FO: Tracking California’s Water Storage
- NASA’s Scientific Visualization Studio
- German Research Centre for Geosciences (GFZ)
- California Department of Water Resources
5 comments
Wow, these satellite findings are mind-blowing! California got some crazy water gains, breaking records left and right. Goodbye drought, hello relief!
Can you believe it?! California’s water situation is finally looking up. Those atmospheric rivers really did their thing, filling up the rivers, lakes, and even underground stores. But let’s not forget, we still got a long way to go.
The GRACE-FO satellite is the real MVP here, giving us the scoop on all those water changes. It’s fascinating how they measure gravity to track the water volume. Mother Nature can be unpredictable, but it’s great to see California getting a much-needed water boost.
As someone who has lived through years of drought, I can’t express how relieved I am to hear about these water gains. We can’t get complacent though. Recharging aquifers takes time, so let’s keep conserving and praying for more rainy days!
Satellite technology never ceases to amaze me! Thanks to GRACE-FO, we can study the Earth’s water systems in such detail. These findings are a testament to the power of data and how it can shape our understanding of climate change and its effects on water resources.