Combined with California’s large population, long history of drought and tendency to be battered by nearly every form of climate change, massive groundwater pumping is aggravating water scarcity, said Xuechen Yang, lead author of the case study and a graduate student in earth sciences at The Ohio State University. “By 2025, more than 5 billion people around the world will live in water-stressed conditions,” said Yang. “Because land subsidence often makes human-made areas uninhabitable, those conditions can cause water and food insecurity issues.” These problems can lead to national security concerns, political instability, and even human migration disasters. To help investigate solutions to these issues, Yang said that researchers are using satellite radar altimetry … Data from radar altimetry satellite missions including European Space Agency’s Envisat satellite, as well as NASA’s and the French Space Agency (CNES)’s Jason-2 and Jason-3 satellites were processed to create a subsidence time series, an data analysis that spanned a decade or longer. After validating the Cryosat-2 derived results, the researchers were able to successfully detect the largest subsidence bowl near the city of Corcoran, California, which sinks at about a rate of about 30 to 35 centimeters per year.