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.
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, 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 month at the annual meeting of the European Geosciences Union. “To say the loss of sea ice has an effect over a particular extreme event, or even over the last 20 years, is a stretch.”
The chief scientist at the Met Office has called an urgent meeting to discuss the effects of climate change, saying the melting of the arctic may be causing the UK’s recent spate of perishing weather.
via The Global Warming Policy Forum
May 12, 2021 at 01:25PM