Operation Iceberg

Travel so far north,

the summer sun never sets.

Here is one of the last great wildernesses -

the vast ice sheet of Greenland.

It's the birthplace of the most massive and spectacular objects

on the planet -

icebergs.

Up to 20 billion tonnes in weight and the height of a skyscraper,

these monsters of the ocean have long fascinated us.

Now, in this series,

an international team of scientists and adventurers

wants to explore these wonders of the natural world.

Wow! Look at that!

I knew it was going to be big, but this is massive.

Just phenomenal.

They hope to discover the secret life of icebergs,

from spectacular birth,

to watery death.

This is a dream come true.

A polar bear on OUR iceberg.

They'll be risking their lives in one of the most unpredictable

and violent environments on Earth.

-It's falling here. -Right.

This whole bit's coming off.

Look at the wave! Look at the wave!

Look at the wave!

That's one of the biggest bits of natural destruction

I've ever seen in my life.

In this programme, the team will be exploring an arctic glacier,

to try to answer how icebergs are born,

from blocks of ice of just a thousand tonnes,

to giant mega-bergs.

That, to me, looks like one great big, white mystery.

Every measurement counts because this is like a knowledge void, a data void.

We've been trying to measure these things in St Paul's Cathedrals,

but I wouldn't know where to start.

If you think icebergs are nothing more than floating chunks of ice,

prepare to think again.

Greenland's glaciers.

Each year, they pump out 20,000 icebergs,

95% of all icebergs in the northern hemisphere.

The iceberg that sank the Titanic came from here.

And one of the mightiest of all Greenland glaciers is Store.

A group of two dozen scientists, divers and camera crew

has now come to investigate this remote glacier.

Store glacier is on the west coast of Greenland,

a 400-kilometre river of ice.

It meets the sea with an ice cliff eight kilometres wide.

The team's base camp will be on a high peninsula,

overlooking this glacier front.

It's the expedition of a lifetime for naturalist Chris Packham.

All my life I've been fascinated by the natural world,

understanding how it works.

I remember as a kid opening my childhood encyclopaedias

and looking in there and seeing glaciers.

This is Store glacier.

It's magnificent.

If you can suffer landscape culture shock, then I'm in it.

It's a logistical nightmare -

five tonnes of scientific and filming equipment,

and enough supplies for three weeks.

Ocean expert Helen Czerski is also fascinated by Store.

I'm a physicist and I study this stuff all around us.

And so looking at that, that's just

like one big jigsaw puzzle to solve from a physicist's point of view.

Andy Torbet used to be an underwater bomb disposal specialist.

Here, he'll be helping the scientists reach places they wouldn't normally get to.

Every morning when I wake up,

that is what I see,

and that is what it's all about.

The medic is Dr Chris Van Tulleken.

This is the kind of injury I absolutely love.

-You're gonna have a nice scar... -Marvellous!

..makes me look a tiny bit heroic,

no one's actually hurt.

As well as treating the injured,

Chris is keen on finding out how the team copes in this harsh environment.

Right, good news, everyone.

I've got another painful experiment, and I need a volunteer.

They've been joined by a group of ice experts from around the world.

We've got three weather stations going in here

so it's nice to see that they've made it.

They're all here to try to understand the birth of icebergs

and, particularly, why glaciers like Store create so many.

All of this ice is moving. It's creeping downwards all the time

and, partly, that's happening because of gravity pulling the ice downwards

towards the sea, down here to where icebergs calve off the front.

But if that was the only thing that's going on,

we wouldn't see as many icebergs down here as we do.

So there's something else.

This restless glacier releases 15 billion tonnes of ice

into the sea every year, peaking now in summer.

Day one and polar cameraman Doug Allan is filming

the birth of a small iceberg.

It's a process called calving.

But it's nothing to what the team hopes to observe -

a multi-million tonne mega-berg.

The problem with calving, as far as I can see, is its unpredictability.

Is there, is there any point on the glacier

where it's more or less likely to happen?

There's a lot of minor activity in this embayment.

It's kinda carved in that way,

but we'll see the big ones out by these peninsulas.

I so, so want to see it.

I'm quite prepared to put up with being eaten alive by mosquitoes

if, at the end of it, I can see one of these things happening.

It'll be great!

We've just got to keep our fingers crossed that someone's

got a camera running when it happens. If it happens.

All right, Doug, would you like a biscuit?

-I'll bring you a biscuit. -Alright.

A chocolate biscuit, thank you very much.

That's what I like about that man.

Like all glaciers,

Store is a constantly moving river of frozen fresh water.

I'm pretty good at that kind of thing!

I mean, Jason's a dab hand, too, with the...

The team's first task is to discover how fast it flows.

British glaciologist Alun Hubbard wants to helicopter in

to plant a GPS tracker to measure its fastest point - the very front.

You think there's a spot we can get down there?

Not to land. I'll just jump out, is the idea.

And um, be a quick game is a good game.

OK. So three minutes, GPS on, right at the headland.

It's extremely hazardous.

This part of the glacier will be the next to collapse into the sea.

He's calculated that if we put this device on,

during the time that we're here, it will break free

and we'll get all the measurements up to that point,

and that's cutting edge. I mean, you know, that's science at the edge.

There's no room for a full camera crew.

Chris himself will have to film Alun.

Can you get on that?

He needs to secure his GPS to the ice.

But he must be quick.

OK. Two, three minutes, OK?

Oh, my goodness me!

Just look at where he is!

Frankly, that is astonishing.

From where Alun is perched on top of this part of the glacier,

there has to be a 100-metre drop,

and he's got a couple of minutes to get that drill,

and get that material in,

and, frankly, if there's any movement on the ice,

there is no chance of him making it off of there.

It's just a pillar with this enormous crack down one side of it.

If I was gonna bet on the next pillar of ice...

The next thing to go, it'd be that one.

The pinnacle has to topple soon.

Alun's instinct tells him it won't be today.

But he cannot know for sure.

Oh, that is astonishing!

He's putting the pole in.

OK, he's ready to go.

OK, take us in, he's got it fixed. He wants to get out of there.

Four minutes, 30 seconds.

The device is secure.

No wonder so little's known about the birth of icebergs.

It's always quite a thrill to be in such a spectacular place.

And, you know, it's a weird space-time thing, isn't it?

Am I here at the right time or the wrong time?

If all goes to plan, the GPS will beam back to camp

the speed at the very front of the glacier.

I tell you something, though, I hope the machine works.

If it malfunctions now and we have to go back...

-Yeah, exactly! -Oh, no, no, no!

The rate the glacier flows

undoubtedly affects the number of icebergs formed.

But how does the glacier,

a four thousand million-tonne slab of ice, move at all?

There's a theory Helen wants to investigate.

Something is helping it along.

The icebergs form mostly in the summer,

so the glacier is flowing fastest in the summer.

And we think there are some clues to why that happens right up ahead.

15 kilometres up the glacier

is a shimmering expanse of water over a kilometre wide.

It's known as a blue lake.

And as we're coming in over the top of it,

it looks like someone's poured blue food dye in there.

Store has half a dozen of these temporary lakes.

They form in spring as the temperature rises

and water begins to pool.

One theory claims water from these lakes drains

to the bottom of the glacier,

and helps it slide across the bedrock.

But is there really enough water in the lake

to move a four billion-tonne glacier?

That's what the team hopes to discover.

Oh, wow! Here's a really nice overlook.

You can really see the colour. That's fantastic.

Canadian glaciologist Michele Koppes believes these blue lakes

help create icebergs.

So what we're really trying to do is try to figure out where does this water go,

and is it contributing to more calving

at the terminus of the glaciers?

So what's happening from here, all the way to the end.

At any moment, the ice below could crack open

and drain the lake, like water pouring down a plughole.

The team want to see how much water collects before it empties.