What Is the Polar Vortex Weather System? — VOA Learning English
Теми: наука й природа

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Weather experts say extreme cold in many parts of the United States this winter has been driven by a polar vortex. But what is this weather system and how does it work?
The National Oceanic and Atmospheric Administration (NOAA) describes a polar vortex as strong westerly winds that form each winter in the atmosphere above the North Pole.
These cold winds move about 16 to 48 kilometers above the surface in the Arctic area in the part of the atmosphere called the stratosphere.
At times, the polar vortex can weaken, causing masses of cold air to break off and move south. A polar vortex can also push warmer air in northerly directions.
The Associated Press (AP) reports that several vortex events…
Торкнись будь-якого слова — переклад з’явиться одразу, а слово ляже в твою добірку разом із реченням.