Listen back to Terry Gross's interview with the Washington Post publisher Katherine Graham and executive editor Ben Bradlee.
Study says global warming will reduce Colorado River levels by 2050
A new study says global warming is expected to reduce Colorado River water levels over the next three decades, but the scientists have widely differing opinions over how much the river will shrink because of rising temperatures.
The Colorado River supplies water to 30 million people in Arizona, California, Nevada and Mexico, so the study released this week by the University of Arizona is bending some ears according to U of A climatologist Gregg Garfin.
“The drought that we have been experiencing has been an eye-opener for a lot of folks," Garfin said.
Garfin said the study compares the findings of 16 recent studies on the Colorado River, and they all confirm that global climate change will take a toll on water levels.
"The projections are for by and large five degrees Fahrenheit by the middle of the century and maybe 8 or 9 degrees Farenheit by the end of the century, and we’re talking about annual temperatures," Garfin said.
Some of the scientists said river levels will drop by 6 percent, and others estimate flows will decrease by up to 45 percent. That is a pretty wide margin, said Ted Kowalski with the state of Colorado Water Conservation Board.
"There’s also a number of climate change models that don’t show decreases," Kowalski said.
Kowalski said the Colorado Conservation Board did not participate in the U of A research.
“It’s a worldwide problem but in terms of adaptation climate change will affect different geographic areas differently," Kowalski said.
Kowalski said President Obama’s Climate Action Plan that was released this week takes some good first steps to reduce the warming that is putting the future of the Colorado in doubt.