The silly notion that AGW is the cause of the extreme cold US winter, or that global warming is producing "global weirding" of weather is debunked by warmist climate scientists including Kevin Trenberth writing in the latest issue of Science. According to the authors, this hypothesis is not supported by either observations or climate models, and AGW would instead cause a tendency for warmer winters and less extreme cold. The authors also dismiss the claim that AGW causes "global weirding" of the weather or a more wavy jetstream.
IN MID-JANUARY, A LOBE OF THE POLAR VORTEX SAGGED SOUTHWARD OVER THE CENTRAL and eastern United States. All-time low temperature records for the calendar date were set at O’Hare Airport in Chicago [–16°F (–8°C), 6 January], at Central Park in New York [4°F (–15.6°C), 7 January], and at many other stations (1). Since that event, several substantial snow storms have blanketed the East Coast. Some have been touting such stretches of extreme cold as evidence that global warming is a hoax, while others have been citing them as evidence that global warming is causing a “global weirding” of the weather. In our view, it is neither.
...we consider it unlikely that those consequences [of AGW] will include more frigid winters.
In contrast to the above examples, the notion that the demise of Arctic sea ice during summer should lead to colder winter weather over the United States seems counterintuitive. But that is exactly what an influential study has suggested (2). The authors hypothesize that global warming could perturb the polar vortex in a manner that renders the flow around it more wavy, leading to an increased incidence of both extreme warmth and extreme cold in temperate latitudes. It’s an interesting idea, but alternative observational analyses and simulations with climate models have not confirmed the hypothesis, and we do not view the theoretical arguments underlying it as compelling [see (3–6)].
U. lecturer argues global warming doesn’t cause polar vortex
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