Last summer climate reporter Sarah Kaplan made a rare visit to

Greenland. She flew by helicopter to a remote corner of the country's massive ice sheet.

You know, I looked down and I just see this like ocean of white.

So we're flying over the Greenland ice sheet and it is just like vast white expanse as far as you can see to the horizon. It's really one of the most unreal things I've ever seen.

And then on the horizon, we saw this just like tiny little pinprick of color and as we got

closer and closer we could see this little cluster of tents yellow tents sort of

sticking up out of the snow and then there was one big red and white tent in the middle and that contained the drill and that was the reason we were all here.

The drill.

scientists were drilling through the ice to try to reach the bedrock underneath, an unprecedented undertaking,

part of a project called Green Drill.

No one has drilled through this part of the ice sheet before that can help us understand what

happened in the

modern climate change.

As the Earth gets hotter, the Greenland ice sheet is melting.

But how fast it might melt and exactly at what temperature isn't clear. And the implications of

this are huge. I mean we know that Greenland Ice Sheet has this capacity to contribute a huge amount of sea level rise in that it's highly vulnerable.

But in order to understand just how vulnerable it is,

scientists really need to figure out what has it done in the past when the earth got warmer?

If scientists can figure that out, that'll give us a sense of sort of what's the temperature

threshold at which Greenland might, you know, sort of tip into this irreversible state of

decline and have we already crossed it and we don't have a lot of time right like

climate change is you know proceeding incredibly quickly.

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