This article discusses how warming is driving much of the Colorado River’s decline, scientists say.
Since 2000, the amount of water flowing in the Colorado River has dropped 19 percent below the average of the past century, a decline that has left the Southwest on the brink of a water shortage.
Now, new research indicates that a large portion of that decline isn’t due to less rain and snow falling from the sky, but to warmer temperatures brought on by climate change.
Scientists from the University of California-Los Angeles and Colorado State University found that about half the trend of decreasing runoff from 2000-2014 in the Upper Colorado River Basin was the result of unprecedented warming across the region.
The study, which was published Aug. 30 in the journal Water Resources Research, is part of growing body of scientific research examining how global warming is affecting the Colorado River and how rising temperatures are likely to affect water supplies in the future.
In another study last year, Udall and climate scientist Jonathan Overpeck used climate models to estimate a business-as-usual scenario of greenhouse gas emissions. They projected that without changes in precipitation, warming will likely cause the Colorado River’s flow to decrease by 35 percent or more this century.