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Is polar ice melting?

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NASA

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The simple and straightforward answer is yes.

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It is, in fact, melting.

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But it's a bit more complicated than that.

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You can think of ice sheets or Antarctica
and Greenland as a bathtub full of water.

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And we want to know how much is going into
that bathtub and how much is coming out.

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So, for instance, snow falling over
the ice sheet is like running the faucet.

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You turn on the faucet,
it fills up with water, and then melting

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when you get a warm atmosphere
or a warm ocean, it's opening up the drain

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and letting water out. So it's not just about melting.

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It's also about how much snow falls
and what the balance is there.

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At NASA, we are able to monitor both Antarctica
and Greenland really easily from space.

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And we have satellite lasers

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that actually measure the thickness of the ice through time.

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And so we can actually monitor where the ice sheets

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are thinning and most rapidly losing mass into the ocean.

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So, is polar ice melting? The answer is yes.

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And at present it is the number one contributor to sea level rise.

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And that's why NASA has scientists like myself

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studying the relationship between ice sheets and sea level every day.