Speedy Arctic warming probably drives excessive winter climate occasions within the US
Hyperlink implicates Arctic warming and its results
September 13, 2021
Amid debate in regards to the affect of adjustments within the Arctic on excessive climate, a brand new research stories that fast warming within the Arctic is a probable driver of latest excessive winter climate in the US. The outcomes are revealed within the journal Science.
The U.S. Nationwide Science Basis-funded findings set up a hyperlink between local weather change and a phenomenon known as the stratospheric polar vortex, or SPV, disruption. Whereas local weather warming is anticipated to result in will increase in some climate extremes, together with warmth waves and precipitation occasions, it isn’t broadly thought-about to drive extreme winter climate occasions.
Nonetheless, opposite to mannequin predictions, winter climate extremes throughout the Northern Hemisphere — intense snowfall occasions and anomalous chilly snaps — have reportedly grow to be extra frequent. One notable instance is the U.S. Southern Plains chilly wave of February 2021, which resulted within the collapse of the Texas vitality grid and file damages estimated at practically USD 200 billion, a value considerably greater than latest high-impact hurricanes.
It’s hypothesized that accelerated warming within the Arctic, also referred to as Arctic amplification or AA, is driving these occasions by disrupting the Arctic SPV — an atmospheric characteristic outlined by the robust westerly winds that encircle the Arctic and, below regular circumstances, preserve its chilly air contained.
Whether or not AA and its impression on the SPV variability are linked to latest winter climate extremes has been unclear; observations and mannequin predictions lack settlement. Constructing on earlier work regarding SPV variability, atmospheric scientist Judah Cohen of Atmospheric and Environmental Analysis and the Massachusetts Institute of Know-how and his colleagues mixed observational analyses of the SPV during the last forty years with new local weather mannequin experiments.
These experiments reveal a hyperlink that implicates fast Arctic warming and its results, specifically sea ice loss and elevated Eurasian snow cowl, with SPV disruption and the elevated frequency of maximum mid-latitude winter climate.
“The research highlights the function of the stratosphere within the local weather system and its potential far-reaching impacts on our floor climate,” stated Varavut Limpasuvan, a program director in NSF’s Division of Atmospheric and Geospace Sciences. “It means that, within the period of AA, the elongation of SPV has grow to be extra prevalent and extra influential as a harbinger of surprising wintertime circumstances.”
The outcomes might be used to increase the warning lead time of chilly extremes in Asia, Canada and the US.
NSF Public Affairs,