Rising Seas And The Groundwater Equation
Professor and director of the Woods Institute for the Environment Barton H. "Buzz" Thompson Jr. was quoted in the following New York Times article on the worldwide depletion of groundwater:
Worldwide overpumping of groundwater, particularly in northern India, Iran, Mexico, northeastern China and the American West, more than doubled from 1960 to 2000 and is responsible for about 25 percent of the rise in sea level, according to estimates in a new study by a team of Dutch researchers published in Geophysical Review Letters.
The general idea that groundwater used for irrigation is running off into ocean-bound rivers or evaporating into the clouds, only to end up raining into the ocean, has been around for two decades or so; it was a focus of a 2005 paper in The Journal of Hydrogeology. But Peter H. Gleick, a leading expert on water issues, said the new paper offers a fresh way of quantifying the phenomenon.
Barton H. Thompson Jr., a Stanford law professor who is co-director of the university’s Woods Institute for the Environment, said the Dutch study could help broaden the lens through which groundwater problems are examined.
“There has been growing recognition that it is not simply a local issue but at least a regional issue,” he said. “If you are living in an area where maybe you’re not depleting your groundwater but other people nearby are depleting theirs, eventually they are going to have to find other water. They may have to find it nearby, and that may be your water.”
What the new study suggests, he added, “is that groundwater depletion is a global problem. Now we have to worry that it’s also contributing to sea level rise. It changes the scale of the problem in a way that perhaps we haven’t thought about before.”
Both Dr. Gleick and Dr. Thompson emphasized the extent to which large agricultural regions in arid or semi-arid areas, from California’s San Joaquin Valley to the Ogallala Aquifer under the Great Plains the Yuncheng Basin in northern China, have become dependent on groundwater to grow the crops that sustain both livestock and people.