Dec 19, 2017

North America's highest peaks are getting double the snow

Brooks Range, Alaska
Sydney Pereira
The Brooks mountain range spreads out to the horizon in northern Alaska March 17, 2011. Photo: Reuters
The Brooks mountain range spreads out to the horizon in northern Alaska March 17, 2011. Photo: Reuters

The tallest peaks of North America are getting twice as much snow since the mid-1800s—and it’s due to warmer oceans hundreds of miles away.

It may sound surprising—even contradictory—that warmer oceans result in more snow in some parts of the world. But there's an explanation. A new study, published Tuesday in Scientific Reports, details how snowfall has doubled on Mt. Hunter, known as “Denali’s Child,” since the mid-1800s. 

“We were shocked when we first saw how much snowfall has increased,” Erich Osterberg, earth sciences professor at Dartmouth College and principal investigator, said in a statement. “We had to check and double-check our results to make sure of the findings. Dramatic increases in temperature and air pollution in modern times have been well established in science, but now we’re also seeing dramatic increases in regional precipitation with climate change.”

Scientists took two 800-foot long, three-inch wide ice samples—technically called ice cores—from Mt. Hunter. Those ice cores reveal 1,200 years-worth of climate conditions data from remains of dust, sea-salts, ash, gas bubbles and human pollutants on layers of the glaciers.


The ice cores revealed that wintertime snowfall has skyrocketed by 117 percent since the mid-1800s in southcentral Alaska and summer snowfall by 49 percent. The increased snowfall is due to a stronger Aleutian low pressure system—the system which causes a blast of warmer, moist air to shoot up from the Pacific tropics to places including Alaska, according to researchers. Warmer air holds more moisture, which in turn causes more snow, according to Winski. And the pressure system only strengthens as greenhouse gas emissions cause the Pacific’s temperatures to increase. The warmer the tropical Pacific Oceans are, the warmer the air is that flows to Alaska.