(Official White House Photo by Pete Souza)
by Olya Schechter
Yesterday, the skies opened up (again), covering much of the Northeast in snow (again). Baltimore and Washington have broken seasonal snowfall records, first dog Bo can barely see over the drifts on the White House lawn and homeowners from North Carolina to New York are digging out from as much as two feet of snow. This excess of winter wonderland has been a boon for global-warming skeptics, quick to mock Al Gore, carbon emissions, and the idea of global warming.
But just as quick to respond were the snowed-in, stir-crazy east coast media elite, always eager to bring down the room with their reliance on "facts" and "science". New York magazine reminded us that focusing on the "warming" part of the now-outmoded phrase misses the point. " 'Global warming’ is an unfortunate misnomer, and unlike its more accurate cousin, 'climate change,' it doesn't reflect that our heating planet can result in all kinds of extreme weather, such as heavier snowfall in certain areas," they write. (We prefer the term "global weirding," as suggested by Thomas Friedman earlier this winter.)
Time magazine, meanwhile, notes that warming may be part of a longer-lasting trend:
But as far as winter storms go, shouldn't climate change make it too warm for snow to fall? Eventually that is likely to happen—but probably not for a while. In the meantime, warmer air could be supercharged with moisture and, as long as the temperature remains below 32°F, it will result in blizzards rather than drenching winter rainstorms. And while the mid-Atlantic has borne the brunt of the snowfall so far this winter, areas near lakes may get hit even worse. As global temperatures have risen, the winter ice cover over the Great Lakes has shrunk, which has led to even more moisture in the atmosphere and more snow in the already hard-hit Great Lakes region, according to a 2003 study in the Journal of Climate.
The New York Times reminds us that this isn't the first time those with a dog in the climate- change fight have used extreme weather as evidence toward their argument, but that doing so can be misleading:
Speculating on the meaning of severe weather events is not new. Hurricane Katrina in 2005 and a deadly heat wave in Europe in the summer of 2003 incited similar arguments about what such extremes might—or might not—say about the planet’s climate.
Climate scientists say that no individual episode of severe weather can be attributed to global climate trends, though there is evidence that such events will probably become more frequent as global temperatures rise.
Still, almost everyone looking to convert the nonbelievers (good luck with that) sent traffic to WunderBlog, the editorial component of the Weather Underground (meteorologist, not terrorist) Web site. There, meteorologist Jeff Masters makes a convincing argument (with data and numbers and everything) that
recent blizzards are in fact corroborating the global warming theory.
As the climate warms, evaporation of moisture from the oceans increases, resulting in more water vapor in the air.
There are two requirements for a record snowstorm:
1) A near-record amount of moisture in the air (or a very slow-moving storm).
2) Temperatures cold enough for snow.
It's not hard at all to get temperatures cold enough for snow in a world experiencing global warming. According to the 2007 Intergovernmental Panel on Climate Change (IPCC) report, the globe warmed 0.74°C (1.3°F) over the past 100 years. There will still be colder-than-average winters in a world that is experiencing warming, with plenty of opportunities for snow.
The more difficult ingredient for producing a record snowstorm is the requirement of near-record levels of moisture. Global warming theory predicts that global precipitation will increase, and that heavy precipitation events—the ones most likely to cause flash flooding—will also increase.
(Interesting note: most TV meteorologists are climate-change skeptics, in part because the rules of meteorology—a.k.a., the daily and weekly variants in weather—are vastly different than the rules of climatology, which deal with the long term heating and cooling of the planet. Also, because some TV weather people MAYBE think they have a better grasp of science than they actually do. Last month, the Columbia Journalism Review did a piece worth reading on why.)