LISA DESJARDINS: Some call it the Doomsday Glacier, a vast expanse of antarctic ice roughly the size of Florida.

Formerly named the Thwaites Glacier, as temperatures rise connected to human activities, it's melting fast and threatens to raise global sea levels.

That's why a team of nearly 40 researchers is embarking on a two-month journey to study it.

And, of course, our science correspondent, Miles O'Brien, is with the expedition.

He joins us now from an icebreaker in the Southern Ocean on his way to one of the most remote locations on the planet.

Miles, let me just start with, where are you and how close are you to this glacier?

MILES O'BRIEN: Sixty degrees latitude, Lisa, about 160 west of longitude, right in the middle of the Southern Ocean.

And, normally, this would be a wild ride, but we have had a very benign cruise so far, having left New Zealand a little less than a week ago, chugging along at about 10 or 11 knots, making our way down to West Antarctica and the Thwaites Glacier.

And the fact that I can have a communication at all with you like this is a modern marvel of technology, the fact that we have satellite-based Internet systems that give us this kind of bandwidth, which we will have with us for the entirety of this scientific expedition.

So it's an opportunity to report on an urgent scientific mission in real time, and that was something I couldn't resist.

LISA DESJARDINS: Well, we're happy to have you on, but I want to ask you.

This is not the first voyage, of course, to Antarctica for scientific purpose, but what's different about this one?

MILES O'BRIEN: Well, this glacier is what's different.

The Thwaites Glacier, as you pointed out, has a tremendous capacity to potentially raise sea levels all over the globe by about 10 feet if it melts and collapses and the ice behind it flows into the sea.

It is unique because it is unstable on a good day.

It sits below sea level.

And, as it happens, where the glacier meets the ocean, climate change has changed the ocean currents such that warm water is lapping right up against it.

And what is happening right now is, it's being eaten away from beneath.

And, as that happens, it accelerates, because it's going downhill below sea level.

So what scientists want to know is, what's the temperature of that water?

How quickly is that melt occurring?

And could it be accelerating in ways they can't predict right now?

No one has ever gotten data from this part of the world ever.

LISA DESJARDINS: Well, that's an astounding thing.

MILES O'BRIEN: Yes.

LISA DESJARDINS: I think the question maybe on a lot of people's minds, though, is, I know you're trying to pinpoint a little bit more about how long this glacier can go, what exactly its situation is right now, but what are the parameters here?

It obviously would take a long time for this entire glacier to sink into the sea, but it doesn't have to raise the ocean level 10 feet to have an impact around the globe.

What are we talking about generally?

MILES O'BRIEN: Well, that's true.

And that's the big question mark.

If you don't know what's happening beneath that glacier, you really can't make a prediction or forecast as to what lies ahead.

So scientists would like to drill a hot water drill hole right at that spot where the glacier meets the land and the sea.

They call it the grounding line.

They want to drop down several instruments to get some instantaneous data.

And then they want to leave behind a mooring that will be attached to a device that can offer real-time constant data of the temperatures at that location over time.

That will give them the insight as to how worried we should be about Thwaites.

The thought is, if it's not an accelerating process, this is not something we have to worry about for quite some time.

But what if it does begin a cascade of acceleration?

That's a big question and quite a troubling one which scientists hope to answer.

LISA DESJARDINS: This, for you, is a lifelong goal, and you are keeping people abreast of what happens through entries, journal entries.

You will be talking to us.

But I wonder what in particular are you curious about when you get there?

MILES O'BRIEN: Well, I'm curious to see science in this very rigorous, difficult environment.

This is a two-month voyage that comes down to just a day or so of key science, when you consider that drill site.

All these scientists work so hard and so long with a very narrow window of opportunity to do their work.

So, for them, it is the ultimate game day, kind of the Super Bowl.

And, for me, as a reporter covering science and climate, I'm thinking of it as kind of a journalistic Super Bowl.

And I have even got the right NFL-style headset to cover it.

So I'm very excited to be there.

I'm very excited to see science that has urgency and great relevance, not to just a few people, but literally the whole planet.

LISA DESJARDINS: The ever intrepid Miles O'Brien, thank you, and we will keep in close touch.

MILES O'BRIEN: You're welcome, Lisa.

Look forward to it.