The Warming Climate Could Scorch America’s West

Scientists see similarities between today’s climate and one that existed 15,000 years ago, when the earth was toasting its glaciers to emerge from an ice age.

Tracy Barbutes/ZUMA


This story first appeared on the Atlantic Cities website and is reproduced here as part of the Climate Desk collaboration.

Long-lasting drought has been the force behind several of this year’s American calamities. Hot temperatures and scarce rainfall set the stage for the explosive development of California’s Rim Fire, turned Utah into one big disaster zone, and prolonged the worst drought in Colorado since the 1950s.

These western areas should brace themselves for even more onslaughts of ugly parching, according to a new study that suggests a warmer climate will bake them (as well as many other places) like a Spicy Wing Zing under a 7-Eleven heat lamp.

Wallace Broecker and Aaron Putnam are researchers at Columbia University’s Lamont-Doherty Earth Observatory who have a keen interest in paleoclimatology, or how the climate changes over the course of history. Whereas many of today’s scientists study data from the past century recorded at worldwide monitoring stations, Putnam and Broecker are digging back thousands of years by looking at things like stalagmites, tree rings, and ice cores. What they think they’ve found is a worrying similarity between the modern climate and one that existed 15,000 years ago, when the earth was toasting its glaciers to emerge from an ice age.

Back then, Arctic sea ice was melting so rapidly it set up a temperature imbalance between the northern and southern hemispheres. That caused major transporters of atmospheric moisture—the tropical rain belt and the mid-latitude jet stream—to deviate from their previous positions and move northward for long periods, as if the planet had hitched up two belts made from water. The resulting change in rainfall patterns starved rivers in Brazil into meager streams and reduced Utah’s Lake Bonneville, once the size of Lake Michigan, into a comparable puddle.

When this grand-scale process reversed itself during the Little Ice Age—a not-quite ice age from about 1300 to 1850—severe droughts that popped up in Asia helped take down China’s Ming dynasty and Cambodia’s Khmer civilization, the researchers say.

All this is background for Broecker and Putnam’s assertion that it could all be happening again today. The Arctic’s frozen stocks of H20 are dissolving at a lightning clip, as shown by these visualizations of how much the sea ice has shrunk each year. This is the ice at its tiniest extent in 1984:

And this is its smallest extent in 2012, measuring in at about half the size it was on average from 1979 to 2000 (the ice is slightly larger in 2013 than last year):

The southern hemisphere is not keeping up with the north’s balmy temperament, the researchers say, setting up the possibility for another climate-warping temperature imbalance. Should the wind and rain belts move locations for the long-term future, the blow to humanity would be “huge,” they say. While monsoon-drenched Asia and equatorial Africa would become wetter, a paucity of moisture above the Amazon, the Middle East, and America’s western flank could create desiccated zones susceptible to droughts, crop kills, wildfires, and other yet-to-be-fathomed problems.

They add that the rain might already be migrating north, “as suggested by a number of recent droughts, including in Syria, northern China, western U.S., and northeastern Brazil.” Here’s Broecker talking about what that might mean for the coming generations:

More Mother Jones reporting on Climate Desk

AN IMPORTANT UPDATE

We’re falling behind our online fundraising goals and we can’t sustain coming up short on donations month after month. Perhaps you’ve heard? It is impossibly hard in the news business right now, with layoffs intensifying and fancy new startups and funding going kaput.

The crisis facing journalism and democracy isn’t going away anytime soon. And neither is Mother Jones, our readers, or our unique way of doing in-depth reporting that exists to bring about change.

Which is exactly why, despite the challenges we face, we just took a big gulp and joined forces with The Center for Investigative Reporting, a team of ace journalists who create the amazing podcast and public radio show Reveal.

If you can part with even just a few bucks, please help us pick up the pace of donations. We simply can’t afford to keep falling behind on our fundraising targets month after month.

Editor-in-Chief Clara Jeffery said it well to our team recently, and that team 100 percent includes readers like you who make it all possible: “This is a year to prove that we can pull off this merger, grow our audiences and impact, attract more funding and keep growing. More broadly, it’s a year when the very future of both journalism and democracy is on the line. We have to go for every important story, every reader/listener/viewer, and leave it all on the field. I’m very proud of all the hard work that’s gotten us to this moment, and confident that we can meet it.”

Let’s do this. If you can right now, please support Mother Jones and investigative journalism with an urgently needed donation today.

payment methods

AN IMPORTANT UPDATE

We’re falling behind our online fundraising goals and we can’t sustain coming up short on donations month after month. Perhaps you’ve heard? It is impossibly hard in the news business right now, with layoffs intensifying and fancy new startups and funding going kaput.

The crisis facing journalism and democracy isn’t going away anytime soon. And neither is Mother Jones, our readers, or our unique way of doing in-depth reporting that exists to bring about change.

Which is exactly why, despite the challenges we face, we just took a big gulp and joined forces with The Center for Investigative Reporting, a team of ace journalists who create the amazing podcast and public radio show Reveal.

If you can part with even just a few bucks, please help us pick up the pace of donations. We simply can’t afford to keep falling behind on our fundraising targets month after month.

Editor-in-Chief Clara Jeffery said it well to our team recently, and that team 100 percent includes readers like you who make it all possible: “This is a year to prove that we can pull off this merger, grow our audiences and impact, attract more funding and keep growing. More broadly, it’s a year when the very future of both journalism and democracy is on the line. We have to go for every important story, every reader/listener/viewer, and leave it all on the field. I’m very proud of all the hard work that’s gotten us to this moment, and confident that we can meet it.”

Let’s do this. If you can right now, please support Mother Jones and investigative journalism with an urgently needed donation today.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate