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Home / US / Polar vortex: What is the weather event of the polar vortex in 2019 and is global warming responsible?

Polar vortex: What is the weather event of the polar vortex in 2019 and is global warming responsible?



Predictors say that millions of people in the Midwest and Great Lakes this week will see record-breaking wind chill conditions from 40 to 65 degrees below zero – cold, so extreme that they can cause frostbite on exposed skin in five minutes or less could. About 100 million people will experience temperatures near or below zero degrees. What you need to know about the polar vortex behind the freezer:

What is the polar vortex?

The cold air will come from a brief visit to the polar vortex – which is not just a real meteorological phenomenon is a sensational headline. It is a swirling mass of cold air that circulates in the mid to upper levels of the atmosphere and is present every winter.

Normally, it stays closer to the poles, but sometimes breaks apart and sends chunks of Arctic air south to the US in the winter

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NOAA


This week's particularly cold break may be explained by the relative lack of cold air this winter in the eastern US. Instead of the cold air, which flows gradually to the south, everything comes at once.

How cold will it come?

The polar vortex will lead to some shockingly cold temperatures this week . The National Weather Service in Chicago predicts that it will be the coldest eruption of the Arctic for 25 years and may be kept for records.

Wednesday's high temperatures in Chicago are expected to be 12 below zero. Low temperatures of 5 to 15 below zero are likely in Indianapolis, Detroit, Cleveland, Buffalo, Albany and Burlington, with winds less than 40 on Thursday morning.

The worst effects will spread from Upper Midwest Tuesday to the Great Great on Wednesday's lakes and through Thursday to the Northeast.

If there is a saving grace for this current bitter explosion, then the cold air mass will not penetrate very far south and the core will remain over the northern third of the nation. The temperatures in Central and South Florida remain above 40 degrees.

How long will the cold last?

The cold explosion does not last very long. The coldest air will be in retreat by Friday. By Sunday, temperatures in the 1950s will return to parts of the Ohio Valley – a 100-degree warmer than the week's lowest showers.

Is the polar vortex connected to climate change?

A counterintuitive theory about the polar vortex In the climate science community some people are gaining ground: Regional cold air outbreaks can be "supported" by global warming. Although it does not seem reasonable at first glance, it scientifically meets the extremes expected by climate change.

Overall, the Earth is warming due to climate change, but areas near the North Pole are warming more than twice as fast as the rest of the world. This "Arctic Amplification" is particularly pronounced in winter.

When warm air enters the Arctic Circle, it weakens the polar vortex and displaces the cold air masses southward into Europe, Asia and the United States. One might think of this as a former tight-knit circulation throwing cold pieces of air outward.

Evidence of this was provided in a research report published in the Journal of the American Meteorological Society. In essence, this suggests that climate change can contribute to a more extreme, rippling jet stream and throw cold air masses further south.

It should be noted that this theory is relatively new and much discussed in climate science is the extent to which such a link exists. CBS News turned to two leading climatologists to see if part of the recent Arctic outbreaks was due to climate change. That's what they had to say:

Dr. Judah Cohen, climate scientist at Atmospheric and Environmental Research (VRE), told us:

I have argued that deep sea ice and extensive snowpack [in autumn] as a result of Arctic reinforcement have more often led to weakening or disruption of the polar vortex in recent decades.

When the polar vortex is weak or "disturbed," the airflow is weaker and winds north and south (and not west to east). This allows air masses to redistribute as cold air from the Arctic flows into the mid-latitudes and warm air is transported from the subtropics to the Arctic.

Dr. Michael Mann, director of the Earth System Science Center of Pennsylvania State University, said:

These questions examine the limits of our two available data (the apparent increase in the frequency of these events is fairly recent and therefore only at the beginning of the background noise and the beginning

As we have shown in our recent Science article current-generation climate models do not solve some of the key processes in jet-stream dynamics behind many types of weather extremes.

Honest scientists can legally distinguish themselves based on reasonable interpretations of the evidence to date.

In conclusion, most scholars involved in this type of research are intrigued by the theory. It is a very active area of ​​research agree that Further investigations and improved climate models are needed to find out the causes and effects.


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