We were cold: Climate change and the polar vortex

Photo via Thinkstock.

Photo via Thinkstock.

Search the words “polar vortex dis­proves cli­mate change” and you’ll get a whole lot of arti­cles saying the exact oppo­site: “The polar vortex in no way dis­proves cli­mate change,” (Wash­ington Post); “No, the Polar Vortex Does Not Dis­prove Global Warming,” (Slate); “Polar Vortex and Cli­mate Change: Why cold weather doesn’t dis­prove global warming,” (Inter­na­tional Busi­ness Times).

So what I’m about to tell you should not come as a shock: The polar vortex does not dis­prove cli­mate change. Indeed, no single cold snap, no matter how freaking freezing it may be out there, says all that much about global warming…or even global “weirding,” as some like to call it.

In 2011, North­eastern asso­ciate pro­fessor Auroop Gan­guly and his lab pub­lished a paper in the journal Geo­phys­ical Research Let­ters, which was one of the first to show that extreme cold weather events–like the one we just survived–will con­tinue late into the 21st even under the worst global warming con­di­tions. As a research high­light in the journal Nature pointed out, their work sug­gested that such cold spells could even be more intense and more pro­longed in the future.

“Nat­ural processes, for example the North Atlantic Oscil­la­tion and La Niña, may con­tinue to play a strong role in cold weather events,” said grad­uate stu­dent Evan Kodra, who led the 2011 study. “They can tem­porarily mask the longer term warming that is expected to accom­pany rising green­house gases.”

Kodra and the other mem­bers of Ganguly’s team haven’t looked specif­i­cally at the polar vortex–which is a nat­u­rally occur­ring wind pat­tern con­stantly in action around the poles–but it’s another example of one of these nat­ural processes that he’s talking about.

As post-​​doctoral researcher Rachindra Mawalagedara explained it to me, the polar vortex usu­ally takes on a roughly cir­cular pat­tern in the upper atmos­phere above the poles. But var­ious things can cause the shape of the vortex to become dis­torted, sending southward-​​reaching ten­ta­cles of frigid arctic air into the nor­mally more tem­perate regions.

Some lit­er­a­ture sug­gests that atmos­pheric warming is ampli­fied near the poles, which leads to polar ice melt,” said Kodra. Since water absorbs more heat than ice does, this could be respon­sible for a tem­po­rary dis­tor­tion of the vortex. “But it would be pre­lim­i­nary at best to make a claim that this one event we’re expe­ri­encing is actu­ally caused by global warming,” he continued.

Mawalagedara explained that it’s the long term patterns–not indi­vidual inci­dents or even short term patterns–that matter when it comes to eval­u­ating cli­mate change. “With our cur­rent state of under­standing, it’s hard to attribute a single event to cli­mate change,” she said.

So, the last few days of unbear­ably cold weather were not proof of cli­mate change nor were they proof of its nonex­is­tence. We were cold and sci­ence sug­gests we’ll con­tinue to be cold well into the future.