Physical Link Shown Between Arctic Warming and Extreme Winter Cold Events

Science, September 3

Rapid warming in the Arctic, including loss of Arctic sea ice seems to be associated with increasing extreme weather events in the Northern Hemisphere, but the cause and therefore the strength of this association has remained uncertain. Sudden warming of the stratosphere above the Arctic has been postulated as one causal link, but this study showed that such events are occurring when polar winds in the stratosphere “stretch” and weaken, sending outbursts of cold air and potentially-heavy snowfall into the United States, Europe and East Asia. Authors found this “stretching” pattern occurred prior to a number of extreme cold weather events over the past decade, including that in February 2021 when snow and below-freezing temperatures caused the isolated Texas electric grid to crash, with over a hundred deaths. Knowledge of this association should help emergency planners prepare for such events in future with greater lead time; but the number and extent of such dangerous blasts of cold Arctic air will continue to rise should global warming not be halted, even as temperature averages and extreme heat events increase at the same time.

https://www.science.org/doi/10.1126/science.abi9167