极涡是该区域四季存在、冬强夏弱、向上延伸至平流层下部的基本环流系统。

Polar vortex is a basic circulation system which exists in every season (strong in winter and weak in summer) and can extend to the lower level of stratosphere.

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这些鸟能在脖极划冷的冬挽溜生存。

These birds able to survive the perils of the Arctic winter.

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善养生者，食不过饱，饮不过多，冬不极温，夏不极凉。

Seventeen, good health, but eat food, drink but, winter is very warm, summer is not very cold.

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