Ice Fierce Earth

This week on Fierce Earth we explore the power of ice.

And where better to start than here.

Welcome to Iceland.

Iceland is one of the least populated countries in Europe.

There may not be many people here

but there are loads of mountains, volcanoes and glaciers.

And it's those glaciers that have brought us here

because on today's Fierce Earth...

The big chill sets in, as we get to grips with ice.

We're going to show you the awesome power of ice as carves its way

through mountains.

Mike will be there as a terrifying winter storm

strikes North America.

Just look at this! This is insane!

And we'll see Leo shoot across ice at super-high speeds.

And we're going to see how this seemingly innocent substance

can be so destructive and dangerous.

What happens when the ground shakes, the seas rise up

and the air tears itself apart?

The Fierce Earth team move in,

taking on the most powerful forces on the planet.

Get ready for Fierce Earth - the Earth and how to survive it.

Ice makes up about 10% of our planet.

There's enough of this frozen substance on Earth to cover

the whole of Britain over 65 times.

Ice takes all kinds of different forms.

It can be glacial ice which forms on land.

Ice sheets which float on the sea.

Or polar ice which forms a frozen desert at the top

and bottom of our planet.

But where does this ice actually come from?

We've travelled all the way to the country of Iceland to show you.

To understand how ice forms,

I'm coming face to face with a gigantic lump of the stuff.

It's called the Svinafellsjokull glacier.

When water gets to about zero degrees centigrade,

it can freeze rapidly and turn to ice.

But that isn't how most of the ice on Earth is created.

Some of the most powerful ice on our planet

starts off as the humble snowflake.

Now it's hard to imagine how simple,

fluffy snowflakes that fall from the sky, can actually become this.

But if you collect enough of them, and you compact them over time,

you can form some of the most powerful ice rivers on the planet.

And the way that the snowflakes are crushed together,

helps scientists like me actually study the ice.

Iceland has some fantastic glacial formations.

When you see them in cross-section,

they tell you the age of the ice, step by step, year by year.

You can pick out dark and light layers.

The light layers represent snowfall in winter.

The dark layers represent dust blown over the ice in the summer.

It's like the rings of a tree.

Winter after winter, new layers of snow fall

and the weight from each layer weighs heavily on the previous one.

The layers get thinner and thinner, making them more dense.

The pretty snowflake shape we know is crushed

and all of the air squeezed out,

until you get to see the dark blue dense ice that we see around us.

And that is how the ice that covers over 10% of our planet is formed.

But as you can see from these speeded up pictures

once it's been created,

the ice in these glaciers doesn't just sit there.

It moves,

and that movement is responsible for the way the land around us looks.

I'm fascinated by how ice has shaped our planet for thousands,

if not millions, of years.

Glaciers are ever-changing.

These huge lumps of ice that move

and gouge out the sides of the mountains to create the valleys.

Glaciers move because of the huge weight

pushing down from the snow and ice at the top of mountain.

Slowly but surely, this huge beast moves forward,

sweeping away everything in front of it.

Thousands of years ago glaciers like this covered Britain too,

and it's their movement, pushing rock and soil in front of them,

that shaped our country as well.

Glaciers are really fascinating powerhouses of our planet.

They represent Mother Earth's bulldozer,

carving the mountains and valleys that we see around us.

From California in the USA to the Lake District in the UK,

the power of ice has helped shape the whole planet.

When it comes to rocks and ice there's only one winner.

And that's ice.

Up on mountains isn't the only place you'll find ice.

You'll also find it floating in the water as icebergs.

How do icebergs get into the sea and what could they mean for our planet?

I've travelled to the south east coast of Iceland to find out.

This is the Jokulsarlon lagoon.

It is filled with icebergs.

The glacier is just up there and that's where the icebergs come from.

They break off or carve and float very slowly down towards the coast.

The lagoon is a brilliant example of how

icebergs are created from melting or retreating glaciers.

80 years ago, this was solid ice

but, since then, the glaciers have slowly retreated.

In doing so, the sea has flowed in,

but the glacier continues to feed the icebergs.

It is an incredible sight.

Icebergs cover the lagoon, there are hundreds of them.

But there's a lot more to be seen under the surface.

To investigate what's going on below the water line,

I've got a little camera here.

It shows me

that almost 90% of the icebergs are actually below the water.

And that means the more you can see of an iceberg above,

the more there is below.

Hence the phrase "tip of the iceberg".

And that's the reason they can cause so many problems for ships.

The largest icebergs could sink even the biggest and strongest of ships.

The one that sank Titanic was over a mile long, now that's a lot of ice.

But big chunks of ice don't just pose a danger to ships.

Ice sheets, that can be as much as 100 miles across,

could have a worldwide effect when they fall in to the oceans.

When water freezes, it expands.

Ice takes up more space than water,

so when a big chunk breaks off an ice shelf the sea level rises.

Although we're only talking about a small rise in levels,

when you combine melting ice with other factors that lead to

an increase in sea levels, it could be serious.

If the sea rises by just 7m,

both London and Los Angeles would be under water.

We don't need to panic...yet.

Melting polar ice and rising sea levels happens over decades

and, by fighting global warming, we can still help to reduce it.

But here in Iceland, something very unusual can happen

that the Icelanders DO need to worry about.

There are fierce volcanoes here that can make huge amounts of ice

melt in a matter of seconds.

To show you what happens when ice meets fire,

I need to get right on top of the ice cap.

Now, that's several miles in that direction,

but I'm going to go in style.

I'm travelling in one of these babies

This bad boy is fully loaded with...

Massive tyres to get us over the snow and ice.

A whopping great engine to get us up the steep slopes.

And a driver that knows the terrain like the back of his hand.

I think we're good to go.

Here we go. You can't really see it outside but on the GPS

You can see this blue line

and that marks the point that we're actually going onto the ice cap.

So although it's a whiteout outside,

the car is now driving on ice. Below us.

This is one of the biggest single chunks of ice

in the whole of Europe.

It's fierce, cold, and a blizzard is blowing.

So we've driven up on top of the ice cap now.

I'm standing on snow

and there's a blizzard around me

but beneath the snow is hundreds of metres of ice

and beneath that is a volcano, Katla. A live active volcano.

And when that volcano erupts it brings hot magma,

hundreds of degrees centigrade, almost 1,000 degrees centigrade,

in contact with that cold ice and it starts to melt,

producing millions and millions of tonnes of meltwater

and when that meltwater is released it is called a jokulhlaup.

And that is what we're here to find out about.

Time to get out of the blizzard.

I've travelled into the heart of the glacier to create

an experiment that will show you what happens when fire meets ice.

So here we are, we've actually come under the ice.

You can see the blue light shining through the ice.

We're actually in an ice cave.

So we're going to do a little experiment.

What we've got here is a couple of holes that we've drilled

into the ice and we've put a little water reservoir in there

and I'm going to start up my volcano here. There we go.

So my little meltwater pocket is trapped.

There we go. There. It's all flooding out now.

This is a very small-scale operation.

You imagine millions and millions of tonnes of water

filling up in a cave just like what we've got around us now.

And then all of a sudden the volcano comes knocking at the door

and - whoosh! - the whole lot comes rushing out in one go,

rocks, ice and debris, all in one big massive flood.

You've got yourself a massive jokulhlaup.

This is a jokulhlaup that hit Iceland recently

and, believe it or not, this is just a small one.

Luckily no-one lived in the area the water flowed through and I'm

now standing right in the middle of where all that melted ice travelled.

This devastated land that you can see all around me

is the result of one of these flooding events

that hit here two years ago.

It's covered an area the size of a small city.

There is no vegetation for miles.

A flash flood, cutting through everything, bringing in debris

and creating, essentially, a moonscape.

There's absolutely nothing left.

If you're here when this jokulhlaup hits,

there's no surviving it.

Like weather forecasters, volcano experts like me

can roughly predict when a volcano is likely to erupt.

And the bad news for the people of Iceland is that the one underneath

the huge glacier I travelled across is expected to blow.

Soon.

When it does, the ice will melt

and unleash a flood with more water than there is in all of Britain's

rivers combined with the Amazon, the Nile and the mighty Mississippi.

But there is hope.

Now the key to survival in one of these flooding events,

is prediction and warning.

If Katla starts erupting,

signals from this station will get sent to Reykjavik.

They can understand those signals

and tell people in surrounding areas that the volcano is becoming alive.

It's that chain of connection

and those chains of events that will help save lives

and allow people to prepare,

ultimately, for a massive flooding event.

The place most at risk

from the flood of icy water is a small town called Vik.

When the warning is sent out, every person who lives here has to

get ready to evacuate.

This is Throan, he's the man in charge of making sure

the town of Vik is empty when Katla erupts and the ice melts.

He'll receive the signal that the volcano is coming to life

and sound the alarm.

When Katla erupts, the amount of water comes down from the glacier.

The flooding, it would take out most of the houses in the lower village

so we have to evacuate the lower part of the village.

We sent directly text messages to all phones in that area to tell

people where to go, what is happening and to try to find a safe place.

After the text message is sent we have to

make sure that everyone has left.

When the alarm rings out across Vik, the clock will be ticking

because the villagers now have just 45 minutes to get out.

This satellite image shows the huge section of land

the glacial flood would threaten.

When they receive the alert,

everyone in Vik must get out of that danger zone.

The risk of Katla erupting and the ice melting is so high that

even the youngest of villagers has to be educated about the dangers.

If we stay here, it could be very dangerous

because the volcano is going to...explode.

Then we have to go high up because there is more safe.

Knowing what to do when Katla erupts could be a matter of life and death.

That's why every few months the kids practise this evacuation drill.

First they're taken to an evacuation centre at the top of a hill,

And from there they are taken even further out of the danger zone.

Only when they have travelled 45 minutes

out of town are the children safe.

I know what to do then. That's why I'm not worried.

It's good to know there's a plan like this in place

and that the kids are ready

because, when fire meets ice here, it spells trouble.

Get ready to buckle up, because later on Fierce Earth,

Leo is shooting across the ice at super-high speed.

But first, you've seen the destructive power of ice on water,

on the ground, as it carves its way through mountains...

..and now it's time to see the power of ice when it forms in the air.

I witnessed its awesome power

when I travelled to Boston in the northeast United States

and found myself in one of the biggest winter storms ever.

Man, we're getting nailed by this blizzard right now.

Just look at this! This is insane!

'It was a scary night.'

You need things like this just to hold on to

because you'll get blown down the road.

'And the heavy snowfall was one part of a winter storm

'I never want to see again,

'but it's what I saw the next morning that really blew me away...

'..cars wrapped in ice...

'..entire rows of houses covered with a layer

'of thick, frozen water.'

Just look at this ice. It's rock-solid.

'I couldn't believe the damage the storm had done to trees,

'houses, and even electrical cables.'

The weight of the ice has taken these power lines

and pulled them down to the ground.

'What were the conditions that made this different to just snowfall?'

To find out, Leo is visiting a special testing facility

in the UK, where normally they run cold-weather tests on cars.

But there's no cars today, just me,

a cold chamber and a couple of bottles of water.

This cold room is about minus ten, similar to a nasty winter storm.

Watch this. Looks like an ordinary bottle of water, right?

Wrong. I'm going to show you a trick. Check this out.

Bang. Turns to rock-hard ice.

In very special circumstances, water like this

can exist as a liquid below zero degrees centigrade.

It's called supercooled water.

And when that water is given something to crystallise around,

like air bubbles when the bottle is slapped,

the ice crystals quickly spread and form solid ice.

I'm about to show you how water like this

can be responsible for devastating ice storms like the one Mike saw.

Now, remember, this is just cold water, supercooled water.

Watch what happens when I pour it on these freezing surfaces.

Here you can see my house,

my dumper truck, just like the one I drive at home,

and I'm going to show you what happens in an ice storm.

Look at that. It turns to ice

immediately, and it stays as ice. And you can see it's layering up

and getting heavier and heavier.

When the supercooled water hits an object like a tree, car

or house that's already cold, it turns to ice.

Imagine if that's the roof of your house, there.

It's starting to get a massive amount of weight on it.

When this happens for real, it can have devastating consequences.

And that build-up of frozen water is exactly what happens

during an ice storm - supercooled water falls through the air

and hits cold objects on the ground, like tree branches.

Layers of heavy ice build up and cause devastating damage.

Some of the most damaging and expensive storms

in North America have been ice storms.

This ice storm that hit Canada in 1998

caused over 1 billion worth of damage, destroyed trees and houses,

and left some people living without power for a whole month.

All that devastation from something as simple as cold water.

That is the power of ice.

CLARE: We're back in the land of fire and ice, Iceland.

As you've seen, ice can be dangerous stuff,

and that's especially true of these things - glaciers.

You can understand why people would want to come here

and experience this most amazing sight, but when an adventurer's hike

becomes the stuff of nightmares, who do you call?

The answer is Iceland's rescue service - ICESAR.

Ice is such a big deal here that these guys specialise

in saving people when they get into trouble on its frozen surface.

There are 18,000 volunteer members of ICESAR,

and they are highly skilled in ice rescue.

They can move like lightning across ice,

using crampons that give them extra grip, ice axes that allow them

to safely climb up and down,

and special rope and ice anchor systems that allow them

to pull people to safety on this treacherous surface.

Today, they're on a training exercise for something they're called out to

most often - crevasse rescue.

Glaciers move on a daily basis,

and as they move, deep cracks in the ice appear.

These cracks are called crevasses,

and its when people fall into them that ICESAR are called out.

So the training that you're doing today

is so essential for saving lives?

Yes, it is.

We have accidents on glaciers and we have to keep updated -

we have to do this over and over again, to increase our efficiency.

Living in Iceland, you... Well, you have to love ice.

OK. Put me into a crevasse. Let's go.

The team are going to do a simple rescue exercise where they lower me

into and out of a crevasse.

It's one of the first lessons they give to new team members.

It's a great chance for me to safely see what it's like inside a glacier,

but I'm still a bit nervous.

That's it, yeah. OK.

On ice, anything can happen.

Oh. Hang on. Hold it tight. That's it.

This is putting science really into action.

I'm going down to a part of the glacier that probably no-one's ever

seen before, and may never see again, because the thing about glaciers -

they're for ever moving.

Oh, it's really deep down there!

The thing is now, it's getting very narrow down here.

-Um... Hang on a sec.

-Stop.

Even though I'm safely attached to a rope,

it's an eerie feeling, being surrounded by ice,

and looking down, I can see how dangerous a crevasse is.

So if you were ever to find yourself on a glacier,

here is the ICESAR survival guide.

First up, never go onto a glacier without a professional guide.

Glaciers change all the time, and crevasses can be hidden

and even covered with snow.

The second survival tip is not to fall into a crevasse

in the first place!

Travel slowly, carefully,

and experienced mountaineers even travel linked together by a rope.

Crevasses can be up to 50m deep.

That's enough of a fall to cause serious injury.

If you are lucky enough to fall onto a flat ledge, stay calm,

stay still and wait for rescue.

You don't want to fall any further.

'Back to my crevasse,

'and I've reached the bottom, and being surrounded by this dark ice

'is enough to make anyone nervous, so I'm not hanging around.'

OK, I think I'm ready to come up now!

I'd be very scared indeed, fearful for my life,

if I fell down one of these crevasses,

but that's why these sort of practice runs are so essential.

Nice and slowly. Hand over hand.

'With one last heave, I'm out. Safety at last.'

Thank you. Thank you.

That's good. On the top of the ice again.

It's the movement of ice that creates crevasses

and the need for many ICESAR rescues,

so, next, Leo's travelled to Switzerland in the European Alps

to find out what it is about ice that makes this slippery customer move,

and how we humans have used the slippery properties of ice

to create super-speed winter sports.

But how do you reach these speeds travelling on ice?

Well, I'm here in Switzerland to show you.

Hidden in a peaceful forest near the town of St Moritz,

this is one of the most famous and feared sports venues in the world.

We're at the famous Olympia bobsleigh track.

This is where the sport of bobsleighing was born.

It's the only track like it on the planet,

and it's only here for a few icy months of the year.

It is the perfect place to demonstrate why ice can appear

to be so slippery when, in fact, it isn't. I'll show you why.

If I take these two chunks of ice and rub them together,

they stick and grate and slide. Look at that.

Nothing slippery about that at all. They're totally stuck together.

But watch what happens now,

when I move this knife blade

over the surface of the ice.

You can see it slides easily. The ice has become a slippery surface.

That's because the thin edge of the blade puts a lot of pressure on it.

Pressure creates heat, melts the ice, and the blade slides over

the water, just like when you slip on a wet floor.

Think about it - that's why the things that move fastest on ice

have really sharp blades, like ice skates or bobsleds.

The sharper the blades, the more heat is created

and the quicker the object moves.

'And today I'm getting to grips with this shiny beauty.

'But first, I need to get some expert advice.'

So what do you think is the top speed I can get out of this thing,

-on this run?

-When you start from the top, then you reach about 125,

226, top-speed.

It feels like a rocket.

Wow - speed into three figures. I'd better get my racing threads on.

Skintight Lycra, nice and aerodynamic so I can go even faster.

This is one of the fastest tracks in the world.

And that horseshoe corner looks terrifying.

And all this in the name of showing you the slippery properties of ice.

-I'm ready!

-OK. Let's go.

-Wahey!

It's a slow start before gravity and the ice start to do their work,

increasing my speed.

And here comes that horseshoe corner.

At this speed, it's difficult to keep control.

And then there's a disaster.

MAN SPEAKS IN GERMAN

Don't worry - it was just one of the cameras!

I've covered 800m in just 15 seconds.

I'm just centimetres off the ground,

and travelling faster than your parents' car on the motorway.

The blades are cutting into the ice, generating heat

and shooting me down this track at over 100km an hour!

This is ice at its most slippery!

That was brilliant. My goodness. You come down so quick,

flying round the corners. there's so little friction on the ice, you're

just whizzing down. Zoom, zoom, zoom. Absolutely amazing.

It's not as violent as I thought it was going to be. You're actually

quite smooth when you're in the bottom, but...

That's so much fun. Can we do it again?

Afraid not, Leo, because our expedition

through the land of ice is over.

On this journey,

we've seen how tiny snowflakes can create mighty glaciers,

how ice storms can bring whole cities to a standstill,

and we've found out what it's like to fall into a crevasse.

Next time on Fierce Earth, get ready for the heavens to open...

It's pouring it down!

..because we're on a soaking journey to the rainiest place on the planet.

-It's going to be wet..

-..and wild!