That is the sound of members of NPR's climate team hiking Greenland's ice sheet.

It's like climbing a mountain and it's three times the size of Texas.

Some of the ice is covered in little pools of water like Swiss cheese.

Water parts rushing rivers of meltwater.

Greenland is losing roughly 280 billion tons of ice a year.

Researchers are trying to figure out how quickly the planet's massive ice sheets and

glaciers will disappear as temperatures rise.

But predicting that is complicated.

Ice ice doesn't melt like the ice in your water bottle.

Dust, algae, and snow all affect how the ice absorbs heat from the sun.

Plus, we're talking huge chunks, the size of entire states.

As it melts the ice cracks and falls into the ocean in large chunks.

And all that melting ice means a lot of fresh water pouring into oceans, which could be

harming the ocean's ecosystems and causing sea levels to rise everywhere.

Now some of the ice loss will continue no matter what at this point, regardless of

what the world does to rain in greenhouse gas emissions in the short term.

But if you look further in the future, it's a different story.

Decisions we make about those emissions now can still have profound effects later this

century.

Here's Twilamune, who is deputy lead scientist at the National Snow and Ice Data Center.

We are 110% not too late.

If we take strong action to reduce climate change and to rain in greenhouse gases, we

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