In a Warming West, the Rio Grande Is Drying Up

Even in a good year, much of the Rio Grande is diverted for irrigation. But it’s only August, and the river is already turning to sand.

The Rio Grande is a classic “feast or famine” river, with a dry year or two typically followed by a couple of wet years that allow for recovery. If warming temperatures brought on by greenhouse gas emissions make wet years less wet and dry years even drier, as scientists anticipate, year-to-year recovery will become more difficult.

“The effect of long-term warming is to make it harder to count on snowmelt runoff in wet times,” said David S. Gutzler, a climate scientist at the University of New Mexico. “And it makes the dry times much harder than they used to be.”

study last year of the Colorado River, which provides water to 40 million people and is far bigger than the Rio Grande, found that flows from 2000 to 2014 were nearly 20 percent below the 20th century average, with about a third of the reduction attributable to human-caused warming. The study suggested that if climate change continued unabated, human-induced warming could eventually reduce Colorado flows by at least an additional one-third this century.

You can read the full story here: https://goo.gl/Bgnn5z

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