by P. Voosen, May 13, 2021 in ClimagteChangeDispatch
Every time severe winter weather strikes the United States or Europe, reporters are fond of saying that global warming may be to blame.
The paradox goes like this: As Arctic sea ice melts and the polar atmosphere warms, the swirling winds that confine cold Arctic air weaken, letting it spill farther south.
But this idea, popularized a decade ago [and was the outlandish plotline in The Day After Tomorrow, pictured], has long faced skepticism from many atmospheric scientists, who found the proposed linkage unconvincing and saw little evidence of it in simulations of the climate.
Now, the most comprehensive modeling investigation into this link has delivered the heaviest blow yet: Even after the massive sea ice loss expected by midcentury, the polar jet stream will only weaken by tiny amounts—at most only 10% of its natural swings.
And in today’s world, the influence of ice loss on winter weather is negligible, says James Screen, a climate scientist at the University of Exeter and co-leader of the investigation, which presented its results last monthat the annual meeting of the European Geosciences Union.