https://www.scientificamerican.com/article/colorado-river-is-in-danger-of-a-parched-future/

The Colorado River is a lifeline. It flows from the central Rocky Mountains of Colorado and Wyoming through five other U.S. states, 11 U.S. national parks and two Mexican states on a 1,450-mile-long journey that supplies water to 40 million people, supports uncounted wildlife and irrigates more than five million acres of farmland. And the river is endangered.

Not only are humans drawing unsustainable amounts of water from this source, but abnormally low precipitation and hot, dry conditions have been shrinking it for years—an alarming trend that is likely to worsen as climate change takes its toll. “To the extent that water is life, the idea that we lose the Colorado River—or even that it is diminished—has an outsize impact on this region,” says Jennifer Pitt, Colorado River Program director at the National Audubon Society. Yet despite the river’s importance, scientists have had a hard time pinning down how much its flow may decline as the world warms. To Chris Milly, a senior research scientist at the U.S. Geological Survey, the question is both disconcerting and fascinating. “I was pulled into the mystery of what was really going on in the river basin,” he says. “My interest bordered on obsession.”