TV meteorologists may be calling it Winter Storm Juno, but climate scientists have a different name for the "once-in-a-century" blizzard that's expected to blanket the U.S. East Coast from New Jersey to Maine starting on Monday.
They call it completely predictable.
"Big snowfall, big rainstorms, we've been saying this for years," says climate scientist Don Wuebbles of the University of Illinois in Urbana. "More very large events becoming more common is what you would expect with climate change, particularly in the Northeast."
The Northeast is the big winner in the "extreme precipitation" sweepstakes dealt out by global warming, with the region seeing the biggest uptick in the severity of the most severe blizzards or rainstorms across the United States.
Amid canceled flights and closed schools, snow with accumulations of 10 to 36 inches (25 to 91 centimeters) was expected to strike a 250-mile-long (400-kilometer) stretch of the East Coast, in a day-long onslaught accompanied by 75-mile-per-hour (121-kilometer) howling winds.
Going to Extremes
Such heavy storms have increased by more than 70 percent in the past six decades in the Northeast, according to the 2014 National Climate Assessment report. Called extreme precipitation, these are the top one percent of blizzards or rainstorms that pack the heftiest punch, threatening sudden floods or paralyzing snowdrifts. The trend has hit nationwide, but with less impact in drier regions such as the Southwest, which has seen only a 5 percent increase in such events.
These storms result from a paradox of global warming in which warmer air temperatures mean more moisture is stuffed into clouds. That's why when it rains—or snows—it pours harder than ever out of those overstuffed skies.
Examples abound of such storms. Aided by the lake effect, Buffalo, New York, saw about six feet (1.8 meters) of snow fall over a few days in November 2014. The Blizzard of 2013, which Monday's storm resembles, according to meteorologist Jeff Masters, dropped almost 25 inches (64 centimeters) of snow on Boston. A 2011 snowstorm knocked out power for thousands of people for ten days in the Northeast just before Halloween.
In New York City, where Monday's storm is expected to break snowfall records, five of the ten biggest blizzards since 1869 have come since 2003.
"We can't make too big a deal of every single storm and say it is caused by climate change," Wuebbles says. "But what we are seeing today is completely typical of what you would expect to see in a warming climate."
Extreme precipitation has increased across the United States in recent decades, but nowhere as much as in the humid Northeast. Overall precipitation has increased by approximately five inches (12.7 centimeters) since 1895 across the region, a more than 10 percent increase, the 2014 National Climate Assessment report says.
And although temperatures have increased by almost 2°F (1.11°C) in that time, those states still see plenty of winter days around the freezing point, when snow falls most heavily.
So when warm, wet clouds meet cold Canadian winds over the Northeast, a storm like Monday's is the result, with National Weather Service weather models "insisting that this storm will evolve into a high impact winter storm/blizzard."
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