|Arctic Forecast: Partly to Mostly Slushy
The sea ice up north is melting. But why? Scientists point to the Arctic Oscillation, a weather pattern where high and low atmospheric pressure swings between the Arctic and lower latitudes. In recent decades that oscillation seems to be favoring its "warm" phase, (circulating arrows) possibly because of global warming, with climatic and economic impacts being whisked around the globe.
When the weather pattern is in a warm phase, low pressure over the Arctic and strong eastward winds at high latitudes hold cold air in the north, keeping winters at midlatitudes mild. When winds push ice out of the Arctic Ocean, open water absorbs sunlight, speeding the meltan effect compounded by relatively warm, salty water pouring in from the North Atlantic.
Since global weather impacts are most visible in the Arctic, researchers come here first to find out what's going onand to predict what a change in the weather might mean for all of us down the line.
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