The polar vortex is a large area of low pressure and extremely cold air surrounding the Earth’s North Pole, typically confined by the strong polar jet stream sustained by the temperature difference between the colder polar region and the warmer mid-latitudes. When this temperature gradient is large, the vortex remains stable and contained near the pole, keeping cold air locked in the Arctic and resulting in milder weather in lower latitudes. However, as the Arctic warms faster than other regions due to climate change, this temperature difference decreases, weakening the polar jet stream. A weaker jet stream becomes wavier and more prone to disruptions, allowing cold polar air to push south into mid-latitudes and warm air to intrude into the Arctic, causing extreme weather patterns. This destabilization leads to more frequent and intense cold air outbreaks in regions farther south and contributes to unusual weather events. The polar vortex also influences the distribution and movement of air pollutants in the Arctic, affecting ecosystems and Indigenous communities.
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