Tom G Farr, Jet Propulsion Laboratory
Water UCI Colloquium Series: InSAR Measurements of Subsidence in the Central Valley, California from 2007-2017
Click here to view the event recording.
Subsidence caused by groundwater pumping in the rich agricultural area of California’s Central Valley has been a problem for decades. Over the last few years, interferometric synthetic aperture radar (InSAR) observations from satellite and aircraft platforms have been used to produce maps of subsidence with cm accuracy. At JPL we have processed InSAR data from multiple satellites spanning the period 2007 – present. As multiple scenes were acquired during these periods, we can also produce histories of subsidence at selected locations and transects showing how subsidence varies both spatially and temporally. Maps and Geographic Information System (GIS) files have been furnished to decision-makers at the California Department of Water Resources to enable better management of groundwater resources and for further analysis of the 4 dimensional subsidence time-series maps.
Tom Farr received BS and MS degrees from Caltech, and a PhD from the University of Washington, all in Geology. After a short time as an engineering geologist, he joined the Radar Sciences Group at the Jet Propulsion Laboratory, where he has been since 1975. At JPL, he helped develop the first geologic applications of imaging radar using aircraft, satellites, and the Space Shuttle. He was the Deputy Project Scientist on the Shuttle Radar Topography Mission in 2000 as well as the lead air-to-ground payload communicator. He has been a science investigator on European and Japanese satellite programs and has studied the geology of Mars, Venus, and recently Saturn’s moon Titan. His current projects include piecing together the history of water in the Sahara with radar images and monitoring of groundwater with orbital radar. He has participated in or led geological expeditions to Tibet, northwestern China, the Egyptian Sahara, and our local deserts, including geology training of Shuttle astronauts.