Exploration of water resources from space was done from the beginning of the satellites era. However, groundwater research from the space was also done and new satellites for that purpose will be launch (GRACE FO). Engineers are not so much aware about it. Here is one article about it.
In recent decades, the over-pumping of groundwater which is used by 1.5 billion people worldwide, combined with drought, has caused some aquifers to permanently lose their essential storage capacity.
With the hope of providing better tools to water resource managers to keep aquifers healthy, scientists funded by the National Science Foundation (NSF) and affiliated with Arizona State University (ASU) and the Jet Propulsion Laboratory (JPL) are using the latest space technology to measure this precious natural resource.
Using high-tech, remote-sensing techniques, the team analyzed data from the 2007 to 2010 drought and mapped the entire California Central Valley, the world’s largest aquifer system – measuring both its groundwater volume and its storage capacity.
The work will not end there. The team hopes to extend the research to Arizona and other areas of the arid Southwest.
(“Now, scientists are developing new methods of monitoring groundwater levels using satellite-based measurements of Earth’s surface, providing a more comprehensive picture of the health of our nation’s groundwater resources.”, says Maggie Benoit, a program director in NSF’s Division of Earth Sciences, which funded the research.)
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