The basic idea, he says, is that hotter conditions create bigger, more energetic waves in the atmosphere that make the jet stream rippler, with bigger peaks and troughs. This affects the rotation of the polar vortex.
Using the analogy of a spinning top, she said, “He seems to be getting cranky about a lot of things.” “It loses its nice round shape and becomes more supple in this case.” One lobe extends into Canada and the United States, favoring cold weather.
Dr Cohen said he has been studying the subject since 2005 and is more hopeful than ever about the changes in the Arctic. “The evidence is only mounting,” he said.
Other scholars aren’t so sure. in short documents In the journal Nature Climate Change in 2020, two researchers from the University of Exeter in England write that despite continued warming in the Arctic and loss of sea ice, there are ongoing short-term trends in extreme cold, jet streams and other climate-related measurements The horizon. The 1990s and 2000s “didn’t last the last decade,” undermining the argument that Arctic warming is to blame.
Some experts suggest that instead of warming, other naturally changing elements in Earth’s climate could be influencing the vortex. Among them, says Ted Shepherd, a climate scientist at the University of Reading in England, is sea surface temperatures in the equatorial Pacific, which can cause changes in arctic air masses that disrupt jets and eddy currents. .
Will this debate be resolved?
Scientists say the question of what role the warming Arctic might play in extreme winters is an example of the kind of healthy climate change debate going on right now. It’s not about whether climate change is real – that question has been answered – but what kind of impacts are occurring, how severe they are and whether they will get worse as warming continues.
Most scholars see this debate as an important ongoing debate. Several aspects, said Dr. Vavros, “has a very solid physical basis”. Among them, he said, was the idea that Arctic warming, by narrowing the temperature difference between the Arctic and the tropics, had weakened the jet stream winds. But there are other aspects, including whether warming is making the jet stream rippler and where, “the stuff that we’re really grappling with and we’re not sure yet,” he said.
“There were a lot of black and white thoughts initially, even among people like me, about this question,” adds Dr. Vavros. “As more evidence emerges, it’s clear there are many shades of gray.”
