In case you think the severe winter storms in the Northeast militate against a warming globe, think again. D-brief’s Eric Betz reports on the latest research:
In late February, an invasion of warm, southern air sent temperatures surging above freezing across the Arctic and toward the North Pole. In the two weeks since then, three nor’easters have smacked New England and the surrounding areas.
As the Arctic warms, this trend has become common in recent winters, and it’s drawn new attention to links between the polar vortex — a constant mass of cold, dense air rotating over the north pole — and weather patterns farther south.
When the polar vortex weakens like it has several times this winter, it can cause the jet stream to buckle and smash cold Arctic air into warm and wet air to the south. The result: severe winter storms.
“This year is a great example — a textbook case,” says Judah Cohen, a climatologist with the private prediction center called Atmospheric and Environmental Research. He says that Arctic heat “set up this parade of nor’easters the past two weeks.”
Weather is a non-linear system, so as we add (or more precisely retain) more heat to the system, strange things will happen. In this case, the winds forming a wall around the North Pole breakdown and the cold mass descends south.
For the unofficial record, Minnesota had a more traditional winter season than we have had over the last decade or so. Or so was my impression when I wasn’t huddled in a sickly pile of pajamas.