Photo credit: Nature World News
Aqueducts in California, one of which is pictured here, are being pumped to combat the state’s current drought. The amount being pumped is causing an increased rate of subsidence in surrounding areas. (Photo : Wikimedia Commons )
Drought Conditions in California are Causing Severe Subsidence
As California continues pumping groundwater to combat the historic drought they are facing, land in the San Joaquin Valley is sinking at an increased rate of 2 inches more per month. The California Department of Water Resources released a NASA report illustrating their findings.
“Because of increased pumping, groundwater levels are reaching record lows — up to 100 feet (30 meters) lower than previous records,” Department of Water Resources Director Mark Cowin said in a statement. “As extensive groundwater pumping continues, the land is sinking more rapidly and this puts nearby infrastructure at greater risk of costly damage.”
NASA compared satellite images taken of Earth’s surface over time to discover this increased rate of subsidence.Interferometric synthetic aperture radar (InSAR) observations from satellite and aircraft platforms have been used over the past few years to produce maps of subsidence with approximately centimeter-level accuracy. Using multiple scenes, researchers at NASA’s Jet Propulsion Laboratory (JPL) were able to produce time histories and profiles of subsidence at selected locations to show the variation over time.
Read the full article: Nature World News