California Groundwater Mapped By Satellite

Satellite technology is now being used to track the movement of groundwater in central California.

The data was gathered using satellite-based InSAR (interferometric synthetic aperture radar) from the Sentinel-1 missions and continuous Global Positioning System (cGPS) data. This allows scientists at the University of California San Diego’s Scripps Institution of Oceanography and School of Global Policy and Strategy, and  the U.S. Geological Survey to observe and map the movement and flow of groundwater through the San Joaquin Valley, the southern portion of California’s Central Valley.

Use of this technology allowed scientists to look at groundwater in a new way, leading to a new view that contradicts the accepted status of the water table in central California.

An uneven distribution of groundwater as it relinquishes itself is in direct contradiction to the widely held consensus that currently exists. Groundwater management agencies currently operate on the basis that everyone, everywhere,will experience the replenishment of groundwater in equal amounts. This now appears to be totally incorrect.

This is a potential game changer for how sustainability will be approached going forward.

“Researchers said their findings have serious implications on how water agencies should think about coordinating their efforts to reach sustainability goals set by the state” – Brittany Hook

Scientists now have the ability to monitor the change in ground level brought about by the presence or absence of water. The satellites measure so precisely that it is possible track the changes brought about by water moving down through the ground to aquifers. The earth’s surface height will actually change plus or minus 2.75 inches throughout the year and in a drought, the ground can sink by as much as 13.7 inches per year.

It’s absolutely mind blowing that something hovering at 2,000km above the earth can measure so precisely!

Methodologies used in this study can be applied to regional aquifer systems across the world, and could prove essential to water management. The use of and access to water will only become more critical as our behaviour changes the planet. The best we can do is use technology in positive ways such as this to understand the effect we have on the natural environment.

With more understanding will come more sustainable practices.

Quotes and excerpts from University of California, San Diego press release. https://ucsdnews.ucsd.edu/pressrelease/scientists-map-pulse-of-groundwater-flow-through-californias-central-valley