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Satellite observations by NASA show sea ice in the Arctic has reached an annual low

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The sea ice receded to an area of 1.94 million square miles on September 17th 2014

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making it the sixth lowest extent on record

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Arctic Sea ice basically acts as a big air conditioner for the planet

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When the sun shines down on it, most of the energy is reflected away

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So it helps to keep the planet cool

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Since 1979, we’ve been monitoring the extent of sea ice with satellites

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and at the present time we’ve lost an area equivalent about a third of the United States

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It goes up and down every year

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but the long-term trend is that we’ve been losing a lot of sea ice

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In large part, what’s been causing the decrease has been heat

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The Arctic has been warming up

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Especially in the last 10 years

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The temperatures in the Arctic have risen about two to three times the global average

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So increases in the global temperature have been

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decreasing the thickness and extent of Arctic Sea ice

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The total volume of sea ice at the end of the summer melt season in 2013

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is about two thirds less compared to 1979

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The lost of Arctic Sea ice thickness makes it less resilient

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If It’s just not as thick, what happens is that it melts faster

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and because of this, it just doesn’t stay around as long in the summer

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It’s important that we’re looking at Arctic Sea ice because of the large impact that it has on our climate

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It’s basically one of the most significant symbols of a changing planet

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