Study reveals extreme winter weather is related to Arctic change

The analysis demonstrates that a relatively obscure weak or disrupted state of the stratospheric polar vortex, where it takes on a stretched appearance rather than the more typical circular appearance, has been increasing over the satellite era (post 1979). Extreme winter weather in the US is more common when the polar vortex is stretched. Both observational analysis and numerical modeling experiments demonstrate that changes in the Arctic, including accelerated warming, melting sea ice and increasing Siberian snowfall, are favorable for stretching the polar vortex followed by extreme winter weather in North America east of the Rockies. Such a chain of events occurred in February 2021, when a stretched polar vortex preceded the destructive and deadly Texas cold wave.

During the past three decades, the Arctic has experienced the greatest climate change of anywhere on Earth, including rapidly rising temperatures, melting sea ice, diminishing spring snow cover, and increasing autumn snow cover. Rapid Arctic warming relative to the rest of the globe is referred to as Arctic amplification. The extent to which these rapid changes in the Arctic are influencing midlatitude weather has become a topic of vigorous debate by climate scientists and popular in the press.