Jul 12, 2025 05:12 AM
(This post was last modified: Jul 12, 2025 05:16 AM by C C.)
https://www.eurekalert.org/news-releases/1090824
Despite a warming climate, bone-chilling winter cold can grip parts of the U.S.—and this study explains why. Researchers found that two specific patterns in the polar vortex, a swirling mass of cold air high in the stratosphere, steer extreme cold to different regions of the country. One pattern drives Arctic air into the Northwest U.S., the other into the Central and Eastern areas. Since 2015, the Northwest has experienced more of these cold outbreaks, thanks to a shift in stratospheric behavior tied to broader climate cycles. In short: what happens high above the Arctic can shape the winter on your doorstep.
INTRO: As winters in the United States continue to warm on average, extreme cold snaps still manage to grip large swaths of the country with surprising ferocity. A new study offers a powerful clue: the answer may lie more than 10 miles above our heads—in the shifting patterns of the stratosphere.
The international team includes Prof. Chaim Garfinkel (Hebrew University), Dr. Laurie Agel and Prof. Mathew Barlow (University of Massachusetts), Prof. Judah Cohen (MIT and Atmospheric and Environmental Research AER), Karl Pfeiffer (Atmospheric and Environmental Research Hampton), Prof. Jennifer Francis (Woodwell Climate Research Center), Prof. Marlene Kretchmer (University of Leipzig).
The study, published in Science Advances, reveals how two specific patterns in the stratospheric polar vortex—a high-altitude ribbon of cold air circling the Arctic—can trigger bone-chilling weather events across different parts of the U.S.
“The public often hears about the ‘polar vortex’ when winter turns severe, but we wanted to dig deeper and understand how variations within this vortex affect where and when extreme cold hits,” said the researchers... (MORE - details, no ads)
Despite a warming climate, bone-chilling winter cold can grip parts of the U.S.—and this study explains why. Researchers found that two specific patterns in the polar vortex, a swirling mass of cold air high in the stratosphere, steer extreme cold to different regions of the country. One pattern drives Arctic air into the Northwest U.S., the other into the Central and Eastern areas. Since 2015, the Northwest has experienced more of these cold outbreaks, thanks to a shift in stratospheric behavior tied to broader climate cycles. In short: what happens high above the Arctic can shape the winter on your doorstep.
INTRO: As winters in the United States continue to warm on average, extreme cold snaps still manage to grip large swaths of the country with surprising ferocity. A new study offers a powerful clue: the answer may lie more than 10 miles above our heads—in the shifting patterns of the stratosphere.
The international team includes Prof. Chaim Garfinkel (Hebrew University), Dr. Laurie Agel and Prof. Mathew Barlow (University of Massachusetts), Prof. Judah Cohen (MIT and Atmospheric and Environmental Research AER), Karl Pfeiffer (Atmospheric and Environmental Research Hampton), Prof. Jennifer Francis (Woodwell Climate Research Center), Prof. Marlene Kretchmer (University of Leipzig).
The study, published in Science Advances, reveals how two specific patterns in the stratospheric polar vortex—a high-altitude ribbon of cold air circling the Arctic—can trigger bone-chilling weather events across different parts of the U.S.
“The public often hears about the ‘polar vortex’ when winter turns severe, but we wanted to dig deeper and understand how variations within this vortex affect where and when extreme cold hits,” said the researchers... (MORE - details, no ads)