Southwestern U.S. Aquifers Are Extremely Low, NASA Data Show

1

Groundwater reserves in the U.S. Southwest are severely low and prospects for their long-term viability are bleak as persistent drought continues to parch the land and prevent recharging, according to an assessment from NASA.

Aquifer-levels-698

As shown in this map, many underground aquifers in the Southwest are extremely dry compared to average conditions over the past 60 years. Deep red areas on the map, such as in southern California and Nevada, depict aquifers that are so dry there’s less than a 2 percent chance they could have experienced such levels of drought-related depletion since 1948.

Although the Pacific Northwest is experiencing drought-related wildfires, aquifers in that region appear to be well-stocked, according to the map. The discrepancy is likely due to the long lag between dry conditions at the surface and depletion of groundwater reserves, researchers say.

This assessment, which NASA considers experimental, is based on observations of small changes in Earth’s mass and gravity field — features that are affected by the movement and storage of water.

About Author

Yale Environment 360 is an online magazine offering opinion, analysis, reporting and debate on global environmental issues. We feature original articles by scientists, journalists, environmentalists, academics, policy makers, and business people, as well as multimedia content and a daily digest of major environmental news. Yale Environment 360 is published by the Yale School of Forestry & Environmental Studies and Yale University. We are funded in part by the Gordon and Betty Moore Foundation and by the John D. and Catherine T. MacArthur Foundation. The opinions and views expressed in Yale Environment 360 are those of the authors and not of the Yale School of Forestry & Environmental Studies or of Yale University.