Scientists are worried about what's happening with the melting of the Antarctic ice sheets and what it could mean for sea level rise and coastlines in many countries.

There's a two-month-long journey underway right now to conduct new research that will better explain what's happening and the role of climate change.

But it's a journey that provides no guarantees that researchers will even be able to get the data they want.

Our science correspondent, Miles O'Brien, is on that ride and filed this report for our series, Tipping Point.

So close and yet so far, after years of meticulous planning and three long weeks at sea, a Korean

icebreaker carrying two helicopters and a team of world-class scientists has made it as far as we had

dared to hope. On January 8th, we moored in the shadow of the most consequential glacier

on the planet, Thwaites in West Antarctica.

But the anchor leg, an 18-mile hop by helicopter onto the ice, has so far been an air bridge too far.

Weather briefings in the wheelhouse of the Aeroon have offered little reason for optimism.

Dominic O'Rourke is the chief pilot.

Hopefully we can fly, scout the camp, maybe tomorrow evening.

The helicopters have flown about as much as the penguins,

and the marquee event of this expedition hangs by a thread.

The ambitious goal, establish a camp on the glacier

to drill a small hole at the place where ice, land, and the sea

meet some 3,000 feet below, the so-called grounding line.

The instruments researchers hope to drop into the seawater would yield unprecedented data to help explain why no glacier is melting faster anywhere on Earth.

That ice is beginning to fall apart in certain places.

Aboard the ship, mathematician and climate scientist David Holland of New York University.

Why all the effort for this one?

This is a special one that over the decades we've discovered

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