Severe winter storms and unusual cold snaps, like the one that hit Texas in February, are, paradoxically, becoming more frequent as temperatures rise, and are linked to rapid warming in the Arctic, according to a new study. For more than a decade, scientists have warned that a warming Arctic and the rapid loss of Arctic sea ice are weakening the polar vortex — a band of powerful, high-altitude winds encircling the North Pole — allowing frigid air to reach further south.
The new study links those changes in the polar vortex to cold snaps like the severe weather in Texas last winter.
“It is counterintuitive that a rapidly warming Arctic can lead to an increase in extreme cold in a place as far south as Texas, but the lesson from our analysis is to expect the unexpected with climate change,” Judah Cohen, a winter storm expert for Atmospheric Environmental Research and lead author of the study, told the Associated Press.
Analyzing changes in the Arctic over the last 40 years, the researchers showed that rising polar temperatures are causing the polar vortex to wriggle and stretch. The vortex is now weakened more than twice as often each year as it was in the early 1980s, according to the study, published in the journal Science. The distortions and stalling of the polar vortex are increasingly delivering uncommonly cold winter weather to the central and eastern United States, while allowing warmer air to flow into the Arctic, further intensifying warming there.
“The Texas cold blast of February 2021 is a poster child,” Jennifer Francis, a climate scientist at the Woodwell Climate Research Center on Cape Cod who was not affiliated with the new research, told the Associated Press. “The study takes this controversial hypothesized linkage and moves it solidly toward accepted science.”