March 28, 2013 9:47 am
Europeans, Brits and North Americans snowed in this spring can thank quickly melting Arctic sea ice for the tumultuous weather, climate scientists say. As the Guardian writes, last autumn sea ice levels on the North Pole fell to all-time lows. As the Artic ice loss escalates, it changes the ocean’s temperature which in turn shifts the jet stream that governs much of the northern hemisphere’s weather patterns.
It’s a tough thing to understand. Less ice at the top of the world, often considered the planet’s thermostat, might normally signal warmer global temperatures, not colder ones.
But the way weather works isn’t so simple. Without a substantial ice cover, Arctic wind is less constrained. The jet stream—the belt of cool air that regulates weather around most of the Northern Hemisphere—then dips farther and farther south, bringing cold air from the Arctic closer to the Equator.
The result is much colder weather dipping into the spring much longer, and more forcefully, than normal.
According to the Guardian, scientists warned in September 2012 that Europe and North America should brace for an extra icy winter, thanks to increase sea ice melt. This problem may also explain last year’s unusually warm winter. The Guardian elaborates:
The hypothesis that wind patterns are being changed because melting Arctic sea ice has exposed huge swaths of normally frozen ocean to the atmosphere would explain both the extremes of heat and cold, say the scientists.
National Geographic warns that seemingly freak weather patterns are likely only to become more and more of the norm in the future.
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