Share

Climate Contradiction: Less Snow, More Blizzards

Seth Borenstein | Associated Press
Published: February 19, 2013

New Haven, Conn.

New Haven, Conn.

A neighborhood near New Haven, Conn., is buried in snow in the aftermath of a storm that hit Connecticut and much of New England. (AP Photo/Craig Ruttle)

  • New Haven, Conn.
  • Bridgeport, Conn.
  • Portland, Maine
  • Hartford, Conn.
  • Boston, Mass.
  • Boston, Mass.
  • Somerville, Mass.
  • Portland, Maine
  • Hyannis, Mass.
  • Hyannis, Mass.
  • Somerville, Mass.
  • Hyannis, Mass.
  • Somerville, Mass.
  • Somerville, Mass.
  • Montpelier, Vt.
  • Somerville, Mass.
  • Staten Island, N.Y.
  • Staten Island, N.Y.
  • North Andover, Mass.
  • Staten Island, N.Y.
  • Staten Island, N.Y.
  • Danbury, Conn.
  • New York, N.Y.
  • Winthrop, Mass.
  • Sea Cliff, N.Y.
  • Buffalo, N.Y.
  • New York, N.Y.
  • Green Brook, N.J.
  • Staten Island, N.Y.
  • Boston, Mass.
  • Boston, Mass.
  • New York, N.Y.
  • Plains Township, Pa.
  • Green Brook, N.J.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Portland, Maine
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Jersey City, N.J.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Lincoln Park, N.J.
  • Jersey City, N.J.
  • New York, N.Y.
  • New York, N.Y.
  • New York, N.Y.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Jersey City, N.J.
  • Jersey City, N.J.
  • Jersey City, N.J.
  • Jersey City, N.J.
  • Boston, Massachusetts
  • Albany, New York
  • Buffalo, New York
  • Boston, Massachusetts
  • Portland, Maine
  • Boston Common
  • New York City
  • Toronto, Canada
  • Boston, Massachusetts
  • Hartford, Connecticut
  • West Bend, Wisconsin
  • Kenosha, Wisconsin
  • Kenosha, Wisconsin
  • Madison, Wisconsin
  • Cambridge, Mass.
  • Cambridge, Mass.
  • Cambridge, Mass.
  • Plymouth Township, Mich.
  • West Springfield, Mass.
  • Detroit, Mich.
  • Plymouth Township, Mich.
  • New York City
  • Springfield, Mass.
  • Holyoke, Mass.
  • New York, N.Y.
  • New York, N.Y.
  • New York, N.Y.
  • Boston, Mass.
  • Brick, N.J.
  • Boston, Mass.
  • Boston, Mass.
  • Boston, Mass.
  • Winter Storm Nemo

WASHINGTON – With scant snowfall and barren ski slopes in parts of the Midwest and Northeast the past couple of years, some scientists have pointed to global warming as the culprit.

Then, when a whopper of a blizzard smacked the Northeast with more than 2 feet of snow in some places earlier this month, some of the same people again blamed global warming.

How can that be? It's been a joke among skeptics, pointing to what seems to be a brazen contradiction.

But the answer lies in atmospheric physics. A warmer atmosphere can hold, and dump, more moisture, snow experts say. And two soon-to-be-published studies demonstrate how there can be more giant blizzards yet less snow overall each year. Projections are that that's likely to continue with manmade global warming.

Consider:

  • The United States has been walloped by twice as many of the most extreme snowstorms in the past 50 years than in the previous 60 years, according to an upcoming study on extreme weather by leading federal and university climate scientists. This also fits with a dramatic upward trend in extreme winter precipitation – both rain and snow – in the Northeastern U.S. charted by the National Climatic Data Center.
  • Yet the Global Snow Lab at Rutgers University says spring snow cover in the Northern Hemisphere has shrunk on average by 1 million square miles in the past 45 years.
  • And an upcoming study in the Journal of Climate says computer models predict annual global snowfall to shrink by more than a foot in the next 50 years. The study's author said most people live in parts of the United States that are likely to see annual snowfall drop between 30 percent and 70 percent by the end of the century.

(MORE: Winter Storm Q Gears Up)

"Shorter snow season, less snow overall, but the occasional knockout punch," Princeton University climate scientist Michael Oppenheimer said. "That's the new world we live in."

Ten climate scientists say the idea of less snow and more blizzards makes sense: A warmer world is likely to decrease the overall amount of snow falling each year and shrink the snow season. But when it is cold enough for a snowstorm to hit, the slightly warmer air is often carrying more moisture, producing potentially historic blizzards.

"Strong snowstorms thrive on the ragged edge of temperature - warm enough for the air to hold lots of moisture, meaning lots of precipitation, but just cold enough for it to fall as snow," said Mark Serreze, director of the National Snow and Ice Data Center. "Increasingly, it seems that we're on that ragged edge."

Just look at the last few years in the Northeast. Or take Chicago, which until late January had 335 days without more than an inch of snow. Both have been hit with historic storms in recent years.

Scientists won't blame a specific event or even a specific seasonal change on global warming without doing intricate and time-consuming studies. And they say they are just now getting a better picture of the complex intersection of manmade climate change and extreme snowfall.

But when Serreze, Oppenheimer and others look at the last few years of less snow overall, punctuated by big storms, they say this is what they are expecting in the future.

"It fits the pattern that we expect to unfold," Oppenheimer said.

The world is warming so precipitation that would normally fall as snow in the future will probably fall as rain once it gets above the freezing point, said Princeton researcher Sarah Kapnick.

Her study used new computer models to simulate the climate in 60 years to 100 years as carbon dioxide levels soar. She found large reductions in snowfall throughout much of the world, especially parts of Canada and the Andes Mountains. In the United States, her models predict about a 50 percent or more drop in annual snowfall amounts along a giant swath of the nation from Maine to Texas and the Pacific Northwest and California's Sierra Nevada mountains.

This is especially important out West, where large snowcaps are natural reservoirs for a region's water supply, Kapnick said. And already in the Cascades of the Pacific Northwest and in much of California, the amount of snow still around on April 1 has been declining so that it's down about 20 percent compared with 80 years ago, said Philip Mote, who heads a climate change institute at Oregon State University.

(MORE: From Tornado to Blizzard in Hours)

Kapnick says it is snowing about as much as ever in the heart of winter, such as February. But the snow season is getting much shorter, especially in spring and in the northernmost areas, said Rutgers' David Robinson, a co-author of the study on extreme weather that will be published in the Bulletin of the American Meteorological Society.

The Rutgers snow lab says this January saw the sixth-widest snow cover in the Northern Hemisphere; the United States had an above average snow cover for the last few months. But that's a misleading statistic, Robinson said, because even though more ground is covered by snow, it's covered by less snow.

And when those big storms finally hit, there is more than just added moisture in the air; there's extra moisture coming from the warm ocean, Robinson and Oppenheimer said. And the air is full of energy and is unstable, allowing storms to lift yet more moisture up to colder levels. That generates more intense rates of snowfall, Robinson said.

"If you can tap that moisture and you have that fortuitous collision of moist air and below-freezing temperatures, you can pop some big storms," Robinson said.

Pennsylvania State University climate scientist Michael Mann points to the recent Northeast storm that dumped more than 30 inches in some places. He said it was the result of a perfect set of conditions for such an event: arctic air colliding with unusually warm oceans that produced extra large amounts of moisture and big temperature contrasts, which drive storms. Those all meant more energy, more moisture and thus more snow, he said.


Featured Blogs

Top 10 Weather Videos of 2014

By Dr. Jeff Masters
December 26, 2014

The year 2014 had many spectacular extreme weather events caught on video; the most remarkable were of flash flooding in Serbia and a tornado in Russia. Two artistic videos that were favorites of mine included beautiful time-lapse pieces set to music taken of monsoon thunderstorms in Arizona and the sunset/aurora on top of Mt. Washington, New Hampshire. Here, then, are my choices for 2014's top 10 weather videos:

November 2014 Global Weather Extremes Summary

By Christopher C. Burt
December 18, 2014

November was globally the 7th warmest such on record according to NOAA and 8th according to NASA (see Jeff Master’s blog for more about this). It was a cold month in the U.S. with some phenomenal lake-effect snowstorms. A powerful storm, dubbed a ‘Medicane’ formed in the Mediterranean Sea. Deadly floods occurred in Morocco, Italy, and Switzerland. It was the warmest November on record for Australia, Italy, Austria and much of Southeast Asia.Below are some of the month’s highlights.

Live Blog: Tracking Hurricane Arthur as it Approaches North Carolina Coast

By Shaun Tanner
July 3, 2014

This is a live blog set up to provide the latest coverage on Hurricane Arthur as it threatens the North Carolina Coast. Check back often to see what the latest is with Arthur. The most recent updates are at the top.

Tropical Terminology

By Stu Ostro
June 30, 2014

Here is some basic, fundamental terminology related to tropical cyclones. Rather than a comprehensive and/or technical glossary, this represents the essence of the meaning & importance of some key, frequently used terms.

2013-14 - An Interesting Winter From A to Z

By Tom Niziol
May 15, 2014

It was a very interesting winter across a good part of the nation from the Rockies through the Plains to the Northeast. Let's break down the most significant winter storms on a month by month basis.

What the 5th IPCC Assessment Doesn't Include

By Angela Fritz
September 27, 2013

Melting permafrost has the potential to release an additional 1.5 trillion tons of carbon into the atmosphere, and could increase our global average temperature by 1.5°F in addition to our day-to-day human emissions. However, this effect is not included in the IPCC report issued Friday morning, which means the estimates of how Earth's climate will change are likely on the conservative side.