As the earth turns and the seasons change,
winter grips the planet.
Of all the elements, cold is our deadliest enemy.
From ice storms to avalanches, frostbite to heart attacks,
cold is a killer.
I'm Donal Maclntyre.
I'll follow winter's advance from its home in the Arctic,
as it brings some of the most dangerous weather on the planet.
I'll be buried alive, frozen solid
and plunged into the lethal white heart of winter.
This is... "Wild Weather"!
My journey with cold starts on the very top of the world.
The Arctic has claimed hundreds of lives
as explorers battle the extreme elements to get here,
but I've chosen a quicker way.
Unconventional I agree, but it gives a bird's eye view
of the top of the wo-o-orld!
(HE LAUGHS)
Amazingly, this beautiful and awesome landscape
is the source of all our cold weather in the northern hemisphere.
I've come here to find out how winter begins.
The Arctic is the area north of 66 degrees latitude
and is frozen all year round.
It's an area of harsh scenery and frozen beauty.
This is the world's largest ice cube.
The scale of this place is breathtaking -
16 million square kilometres of solid ice.
That's bigger than India and China put together.
What's strange is that there's very little weather.
I expected blizzards and blinding snowstorms.
It's sunny, there's a light breeze and very little snowfall.
It's just like a desert. In fact, it's classed as one -
a desert that's permanently frozen.
To find out how this place generates our winter weather,
we have to know what keeps it in this state.
We think of Earth as a blue planet, but looked at from above it's white,
frozen solid all year round.
That's because the planet is tilted on its axis.
In winter, the Arctic is turned away from the sun,
it's always night, and the temperature can plummet as low as minus 50.
Winter shrouds the northern hemisphere.
As the year passes, the earth continues its orbit
and the North Pole tilts towards the sun,
the seasons change and summer returns to the north.
Up here, the sun shines pretty much 24 hours a day,
which is why it's called the Land of the Midnight Sun.
Even this is not enough to break cold's grip.
In the Arctic, as you can see from my shadow,
the angle of the sun is so shallow, its rays bounce off the surface,
reflecting its energy rather than absorbing it.
This keeps the temperature of the surrounding atmosphere constant,
perpetuating the polar climate.
Even at the height of the Arctic summer,
temperatures only creep above freezing, but it's not enough to melt the ice.
Just as well, as I'm not standing on solid rock
and a few metres beneath my feet is the Arctic Ocean.
To prove it, I'm going to take a look...
because this vast layer of ice holds the key to cold's grip on the poles.
It's spectacular, a layer of ice up to ten metres thick,
and it's all frozen fresh water.
There's as much salt in it as your home freezer,
because when sea water freezes, it locks out the salt.
This vast, fresh water ice sheet above me
is the key to winter's energy.
The ice keeps the air immediately above it at almost the same temperature.
Above this layer, warmer air is also sinking down,
which forces the colder surface air to slip south.
This shimmering air looks just like a heat haze,
but it is the first wisps of the polar wind.
This is what carries winter out of its Arctic lair.
This icy blast accelerates the further south it travels.
I'll follow the polar wind as it brings the wildest,
most destructive weather into our world.
This far north, east and west have little or no bearing.
From here, all directions point south,
which leaves me, as it does winter, only one way to go.
Even a thousand miles south of the North Pole,
cold still grips the planet.
Even here, faced with the worst extremes of cold weather,
people make their homes.
This is one of the most northerly inhabited settlements on the planet -
Ittoqqortoormitt in Greenland.
It's home to one of the most hardy peoples on Earth, the Inuit.
If they can survive out here, maybe they're different from me.
- Great to be here. - "Nice to meet you. "
The weather here is among the most extreme on the planet.
In winter, temperatures can drop to minus 40.
Children can only play outside for ten minutes
before their skin freezes solid.
But a lifetime's exposure can prepare you for the worst.
How do you survive here?
I've three pairs of gloves under here and mitts.
My fingers are still cold. How can you keep so warm?
When I was young and began to hunt I also freeze very much.
I learned to use my hands, even when very cold.
It's training.
So the Inuit are no different from me.
We're simply not designed for cold, because we evolved from the tropics,
and even after thousands of years of Arctic weather,
the Inuit have few physical adaptations to the cold.
Inventiveness, not evolution, keeps us alive -
clothing, shelter, heating.
Only a madman would challenge the Arctic cold without protection.
To see what it does to me, I've come to a controlled environment
to find out what happens when the body is exposed to extreme cold.
Not the best place to be in your underwear.
According to cold expert Dr Frank Golden,
most people can only stand this cold for half an hour.
I'll be constantly monitored and, unlike the real Arctic,
I can walk out of here any time.
- "Good luck. " - Thank you very much.
The temperature is minus 18, it's bloody freezing.
Not the best place to be with no clothes on,
but it's getting my temperature down quickly, for my body to react.
Our bodies keep our vital organs at a stable 37 degrees Celsius.
It's called the core temperature.
I'll have to work overtime to try and maintain it.
He's not long in the cold but he's beginning to shiver.
He's shivering to produce more heat, to counter the heat loss.
His elbows are close to his side, his arms across his chest.
He's trying to shut down the surface area
from which heat is lost to the environment.
The only way to try to keep warm is to move.
He's not sure what to do with his body.
He knows he can't generate enough heat by shivering,
so he's not sure whether to exercise more to produce heat.
His temperature is falling and there's nothing he can do.
After just a short time, my body can't generate enough heat
and my temperature is on the way down.
My core temperature has fallen two degrees,
which means I'm hypothermic.
My muscles are stiffening and my brain is cooling.
If I lose my wits, I have no chance.
Even shivering stops as the muscles slow down.
Now a little test.
Count down from a hundred, taking seven away each time.
- "A hundred minus seven. " - Hundred minus seven, O"K".
Hundred minus seven, ninety three.
- "Minus seven?" - Er...
Eighty... hundred minus...
Eighty six.
I feel I've got the flu, I've a headache.
As the vital organs cool, the body starts to shut down.
This is the critical stage.
Then he would become tired and would like a little sleep,
but to survive you've to fight through that phase
and be determined to keep alive, keep going.
Eventually however, the conditions will overcome him
and his temperature will fall below a level of consciousness
and he'd die.
Arghh!
If my body temperature drops by six degrees,
I'll lose consciousness and death is inevitable.
He's in pain now.
Oh, God...! I don't want to be here.
It's time to pull him out, he's had enough.
Y"ou've had enough. How are you?"
Y"ou're bitterly cold. " Were you shivering a lot?
- "Are your muscles stiff?" - My toes feel they'll fall off.
Y"our muscles are stiff," you can hardly talk.
Let's get you warmed up and check you out.
In the real world, we need our brains to survive.
If I can't last 40 minutes in minus 18,
how will I survive here at minus 30?
Erik Bruin and Mads Vadel must know.
They've the most extreme tour of duty in the world.
Three months at a time, the Danish Sirius Patrol
travel the wastelands of north-eastern Greenland
with only their training and a dog sled for protection.
For the next 24 hours, I'll join them
to find out how they survive in nature's freezer.
- "Hi, Erik. " - Hi, I'm Donal.
My partner, Mads. Welcome to Greenland.
These are your dogs? They're wonderful, beautiful, gorgeous.
- They don't bite? - "No. "
It's time to go.
(CALLS DOG'S NAME)
(REPEATS THE NAME)
It didn't work!
That's how you start, how you learn.
Learn to ski before becoming a member of the Sirius Patrol!
It was the weather that first brought them here.
In WWII, the Danish had to defend Greenland from the Germans,
because knowing the weather here, you can predict it in Europe.
Today, the biggest threat to their patch is from the seals -
and of course amateurs like me.
Still, highly-trained professionals
like Erik, Mads and... me, are vigilant.
Blizzards and snowstorms can strike without warning,
and cold is a constant threat. Temperatures regularly fall below minus 40.
Whoah!
Being out in the cold, absolutely everything freezes,
including my left eyelid.
I've been told that if your eyelid freezes like that,
put your hand to it to melt it, then you can open your eye.
It's dangerous to try to pull it open. I'll give it a try.
I can feel it melting, that's a good thing.
I feel as cold as I probably look... now that's fine.
It shows that you've to be careful, cold is a killer.
As night falls, the temperature plummets.
There's only one tent, so what happens to me?
I'm about to be buried alive.
Digging a hole deep into the snow
can offer life-saving shelter, or so I'm told.
What do we do?
We start making an entrance,
then dig in, making it as long as you are, in that direction.
Y"ou will lie about here. "
- "Now we dig in and start. " - O"K".
- That's my home, excellent. - Y"our home. "
Shall I go in?
I'll spend a night alone as the temperature drops below minus 30.
I'm a bit apprehensive about being buried alive out here.
All I'll have is a sleeping bag and some candles.
It's about a metre and a half high, two and a half metres long,
and... about... a metre and a half wide.
My entrance has a gap for oxygen to come through.
An emergency link with Sirius Patrol if anything goes wrong,
if this starts to cave in - which it shouldn't as it's well built.
Hi, guys, Donal here. No worries and see you in the morning, over.
O"K".
I'll see if they respond. If not, well...
I hope they'll be listening if something did go wrong.
It's the middle of the night, minus 30 outside.
One big problem in the Arctic
is that any exposed skin will get frostbite after a few minutes.
Brings me to the problem of going to the toilet.
Don't think so.
(BAR"K"ING)
The temperature inside the hole
stayed 25 degrees warmer than outside.
The snow works as a good insulator.
I spent the night in what, for the Arctic,
was a cosy minus five degrees.
- "How have you been?" - Morning, guys, good.
- "Want a cup of coffee?" - That's a great idea.
The Sirius Patrol are trained to cope with severe Arctic weather,
but when it hits the places we least expect it,
the consequences can be horrific.
This isn't Greenland.
This is New York State in early spring, 1993.
Four feet in front, our tracks were gone,
couldn't find where we'd come from, it'd gone.
The wind blew us down, our eyelids froze.
We held our hands up to stop the stinging.
The 12th of March, 1993, saw the entire east coast of the U.S.
Gripped by one of the wildest storms in history.
Satellite shows a huge storm system coming up the coast.
Moisture colliding with the cold air
means very heavy snows for our region.
12-24 inches for the capital by mid-day tomorrow.
In upstate New York, Geoff Smock and Bill Simmons
were relaxing after work.
Several hundred miles away, the storm was growing
and heading their way.
It had started to snow, but that wasn't unusual for the time of year.
As they set off home, they had no idea
they were about to be overtaken by a blizzard
that would change their lives forever.
Full blizzard conditions in the capital and west New England.
Thunder snows, high winds and dangerous cold.
The snowfall was extraordinary.
Bill and Geoff ground to a halt just half a mile from home.
They decided to walk, and that's when their nightmare began.
Y"ou couldn't go" forward or backwards,
right or left, no place to go.
It was like ploughing through five foot of snow,
then you get exhausted and you look up
and the snow banks are up here and you're in a hole.
We originally thought we'd stay at the tree
until the wind calmed down,
then head back home, but the weather got worse.
By now, winds were gusting at 145 mph,
temperatures had plummeted way below zero
and snow was drifting as high as ten metres.
Over the state, the blizzard was tightening its grip.
(TV) Death toll from the blizzard is mounting, seven people dead.
Make no mistake, this is an emergency.
Back at the tree, the storm was getting worse.
Geoff and Bill had been stuck for eight hours.
I couldn't walk. Ten feet from the tree, my feet gave out.
I couldn't even stand up. I tried but couldn't.
I crawled back here.
I said, "Bill no one's looking for us. "
- "No one knows we're here. " - "Right. "
As the night wore on, the temperature dropped lower,
hitting Arctic extremes of minus 40 degrees.
And still the storm raged around them.
By morning, they'd been exposed for 18 hours to Arctic conditions.
Amazingly, they were still alive.
Geoff struggled through the snow and raised the alarm.
It took six hours before the rescue services got to Bill.
The cold had left a devastating legacy.
During hours of exposure, they'd both suffered winter's vicious touch.
I tucked my hat in my shirt and pulled up my clothes
and exposed my back and part of my buttocks.
I got severe frostbite.
There's no feeling, the nerves are gone, there's scar tissue.
They did skin grafts, on the back of my legs, twice.
My feet, hands, butt, my knees have got it in spots,
the calves of my legs from the way I was sitting.
My hands were blistered, they were as huge as softballs.
Deep frostbite is a one-way process.
The cold literally freezes the skin tissue.
Ice forms in the fluid in and around the cells.
The tiny blood vessels freeze solid and no oxygen is delivered.
Worse is to come. With no blood supply, the cells can't fight infection.
Gangrene sets in, the affected area becomes black and starts to decompose.
At this stage, there's no option but to amputate.
After his ordeal in the freezing cold,
both Geoff's feet were severely frostbitten.
In the end I had skin grafts on my hands, butt and legs.
I lost both feet from about four inches above the ankles.
A wild weather event like this is rare, unexpected,
which is why the cost is so high.
The key to survival is to be prepared.
Even the professionals can get caught out.
In the last 50 years, the Sirius Patrol
have lost six men under the ice.
Severe frostbite is always a problem,
but they know the risks,
and their love of this landscape far outweighs the dangers.
As the Sirius Patrol travel north into the wilderness,
I'm on a different journey, travelling south with the cold
that brings winter to the people of the northern hemisphere.
I'm going to a place that gets the first blast of winter's icy grip.
All that polar wind screaming south is about to crash
into the warmer air from the equator.
When they meet, all hell breaks loose.
In the front line is Mount Washington weather station
in north-east America.
It's here the battle between hot and cold begins.
For now, at least, all is quiet.
This is the highest point in the north-eastern United States,
though it's not that high on a world scale.
It's known as the home of the world's worst weather.
The temperature outside is down to minus nine degrees,
with a north west at 48 mph.
The forecast begins with clouds and snow showers
and winds to the west, 40-60 mph,
but another system will push in from the Great Lakes later.
How does a sun-kissed mountain get such a bad reputation?
The summit lies in the path of the principal storm tracks
and air mass routes that affect the weather in the north east.
It's the perfect place to discover
what happens when wind and cold combine.
Welcome to the home of the world's worst weather.
Good to be here. The mountains look good to us today.
Y"ou should have" been here yesterday.
I came here to find the worst winds in the world
and the weather was perfect!
I didn't have to wait long.
A few hours later, I saw why this place gets its reputation.
Within minutes, the blue skies turned to grey
and the winds kicked up.
The highest wind ever recorded was here at Mount Washington -
a staggering 231 mph!
The wind now is gusting at 60 mph
and I'm being tossed about - it's very difficult to stay up.
The first thing you notice when the wind gets going
is that it feels much colder.
This effect is called the wind-chill factor.
At winds of 50 mph, minus five feels like minus 38.
Wind and cold together multiply the deadly effects of winter.
Which is why the Mount Washington Observatory
is the best place to study the extremes of winter weather.
That's if the instruments don't ice up!
When wind and cold fog like this meet an object,
something truly amazing happens.
The surrounding fog is made of billions of water droplets.
Strangely, they're all way below the freezing point
but remain in liquid form called supercooled.
When they hit an object, they freeze solid.
These beautiful feathers of ice are called rime ice. It's as tough as nails.
This remarkable ability of water to remain a liquid way below zero
is the cause of one of the most extraordinary weather events on the planet,
an ice storm,
and one of the worst ice storms in history hit eastern Canada with a vengeance.
This was the most destructive, disruptive storm in Canadian history.
We've a century and a half of weather keeping in Canada
and there was nothing to match this.
Ice storms are not unusual in Canada,
coating the landscape with a beautiful shroud of ice.
But in January 1998, Canada was hit by a storm that was anything but usual.
At first, the ice storm of '98 was just as magical.
It was really more of an exhilaration.
People were not too disrupted by that.
School was cancelled, businesses closed,
but it was a winter wonderland,
a wonderland where the landscape looks so beautiful.
On the 4th January, winter was still on the attack.
A bank of freezing polar air blanketed the north east,
while a mass of warm, moist air from Texas
moved in above the polar air, forming a wedge, trapping it beneath -
perfect conditions for an ice storm.
But in the middle of the wedge, rain from the warm air above
doesn't have time to freeze solid on its way down,
so it falls as supercooled rain.
The raindrop will fall through the wedge of cold air
and the liquid raindrop will begin to cool.
But it doesn't quite freeze.
It freezes to the point of supercool
which is below freezing point, but it is still liquid.
Because the object it hits is below freezing,
it's almost shocked, it makes the perfect transformation
from the liquid to the solid, spreads out and freezes
into a little veneer of ice -
the toughest, most adhesive ice nature can produce.
Ice storms can be lethal,
but usually the misery only lasts a few hours.
The ice storm of January 1998 was different - it arrived in waves.
For two days, the freezing rain kept coming.
The ice kept getting thicker and thicker, the wires got bigger.
The trees were building up with ice.
See the thickness of this ice compared to my handl
Y"ou could have four inches of ice" around a small twig.
And that twig is part of a branch, also encased in ice.
It now has a different weight and it'll break and fall to the ground.
This condition kept up for hour after hour,
then gradually the trees started coming down.
Then the lines started coming down.
The lines were falling due to the weight of the ice on them.
By the third day, the rain stopped, but icy conditions continued.
Then satellites monitoring the storm saw another wave hit.
Thousands of square miles came to a virtual standstill.
Life was almost impossible.
(TV) The freezing rain won't let up.
If you don't have to go out, do not, unless necessary.
On the Friday we called Black, Dark or Cold Friday,
we realised this was more than the usual ice storm.
We lost power for more than half of the province.
Lines of cables and huge transmission towers
were crumpled to the ground like paper clips.
Y"ou saw electrical pylons" buckle in front of your eyes.
Y"ou knew this would be major," major problems.
Imagine looking down this line of poles
and you see them coming down one after another,
and you see the fireballs as the electricity is cut.
It was like a war zone, it was so devastated.
The ice struck at the heart of modern life.
Every house, factory and office
in an area of half a million square miles was blacked out.
Without power or communications
Montreal hit crisis point.
A centre was set up to co-ordinate emergency efforts.
(TV) It's been called the worst weather crisis
eastern Canada has ever had.
Millions had no heating, fresh water or sanitation.
The situation was fast getting out of control,
emergency services couldn't cope,
and the government was at a loss as to what to do.
We could see desperation.
Temperatures plummeted to minus 15, minus 18.
Even after the ice storm passed, it took three weeks
to restore power and get the city back to normal.
For four million people, this ice storm was...
the weather event of their lifetime, never endured again.
50,000 people were forced to leave their homes
and take refuge in temporary shelters.
35 people died and many more were left in a critical condition.
3,000 kilometres of power lines were destroyed,
at a cost of over $800 million.
200 years ago, there wouldn't have been a storm.
The ice would have come and the ice would have gone.
People had wood stoves to make muffins, it wouldn't bother them.
Today, we depend on electricity, so it was very devastating.
In our endless battle against the cold,
the weather won and our technology was useless.
As my journey with winter continues south,
cold weather becomes less extreme
but can be even more dangerous.
To prove it, I'm off to the cold death capital of Europe.
Moscow? Helsinki? No...
London.
Just because you can't see the ice and snow
doesn't mean that cold isn't a killer.
In Britain, we rarely experience the extremes
that winter brings, like ice storms and blizzards.
Surprisingly, there are more cold related deaths in London
than anywhere else in Europe.
In the mild climate in Britain,
we don't feel we need to dress warmly against the cold.
But even these temperatures can be deadly.
Even in water well above freezing -
say ten degrees Celsius, 50 Fahrenheit -
one in six will be dead after just 15 minutes.
It's a cold morning,
and the water in this lake is nearer five degrees.
Sorry... I forgot that line.
The water in this lake is nearer five degrees.
Even a quick dip...
even a quick dip, as the heart rate monitor should show,
is enough to send my body's defences into overdrive.
My progress is being monitored by Dr Rosemary Leonard.
Put the towel round you. Y"ou're shivering. How do you feel?"
Let's see what's happened to your pulse and blood pressure.
My pulse was 50 per cent faster than my normal heart rate.
Now my blood pressure.
160- that's high.
- "160 over 100." - What's that telling us?
The blood vessels in the outer part of your skin
and to an extent in your body, are narrowing
to conserve the heat and blood flow
to where it's needed, round your heart and lungs.
This is the normal response.
As the blood vessels constrict,
my blood becomes thicker and stickier.
It's this everyday reaction to cold
that can sometimes cause a sudden and painful death.
It's a story that repeats itself every day across the city.
A cold winter's morning, a commuter hurries to the station.
The rush hour has begun. It could be you.
- "Cold this morning. " - Y"eah. "
No hat, no scarf, no gloves.
So what? It's cold but not snowing.
As you wait, your body is already shutting down
the blood vessels nearest to the exposed skin.
As you shiver, your blood is starting to thicken
and retreat back to your vital organs.
As it gets thicker and stickier, the nightmare scenario begins.
A tiny clot starts to form.
As you worry about being late,
the clot is on time to reach your heart.
That night, you suffer a lethal heart attack
and never make that journey again.
The coroner's report adds you to the statistics,
"death by natural causes".
Figures show that in London over 3,000 extra deaths
happen like this every winter.
Across the U"K", the figure is closer to 20,000.
All victims of an invisible serial killer, cold.
The tragedy is it could easily have been avoided.
Mother was right, all you need is a hat and gloves.
Further south than London, winter's grip is less extreme.
Unless you go up high, where cold is always with us.
On top of the mountains or high in the clouds,
there is always snow, even at the equator.
Wherever you are in the world, there will probably be snow above you.
Most of the time it falls as rain,
but at high altitude it falls as snow.
It's one of nature's miracles
and winter's most distinctive hallmarks.
Snowflakes start life as tiny particles in the clouds.
Water droplets are attracted to their surfaces
and freeze, forming ice crystals.
More and more droplets are drawn to the crystal,
which grows into a snowflake,
eventually getting heavy enough to fall to the ground.
The classic six-sided snowflake is the most common,
but it's only one of several different types.
This is a plate.
And here, two plates are joined by a column.
They combine to form even more complex shapes as they fall.
Needles, columns and plates form the basic building blocks.
Under the electron microscope, extreme close-ups of snowflakes
reveal their almost unbelievable complexity...
the weather's miracle of engineering.
Each different type of snowflake forms a different type of snow...
all with extraordinary properties.
Some can be as strong as concrete, which is just as well
if you're caught in a storm with Peter Marchand.
Peter, a snow lover and winter scientist,
spends weeks researching in the snowy hills of Colorado.
He needs nothing but a few feet of loose snow.
Ever since my father got me out on skis as a child,
I became interested in snow as a material.
When snowflakes fall to the ground, they don't remain soft and powdery,
but bond together into a solid mass.
It's this bonding process
that allows nature to make these wonderful snow sculptures.
It also allows Peter Marchand to build himself a shelter.
I'm building a snow house. It's called a quinzhee.
The process is almost magical.
Piling loose powdery snow puts pressure on the surface of the snowflake.
It melts, forming a thin layer of water
which sticks the neighbouring crystals together.
Over time, the water freezes, bonding the snowflakes.
Give it a couple of hours to complete the bonding process,
then dig it out and have a nice shelter for the night.
A few hours later, the pile of snow is a solid block
that Peter hollows out to form a sturdy shelter
against the wildest winter weather.
It's a strong structure which gets stronger with time.
It can be used over and over again.
Y"ou can move on" and come back to them.
It's really a beautiful material.
Free of charge.
It's as easy to build as it is to walk away from.
There's nothing to fold up, put on your back,
or on your pack animals and carry with you.
Mark Twain said of the cold in north America,
"If the thermometer had been an inch longer
"we'd have frozen to death".
Though we complain about the cold, winter has its pleasures.
The same bonding effect that built Peter's snow shelter
is what makes the perfect surface for winter sports.
When that bonding fails, the results can be terrifying.
Looked left - a crack, looked right - a crack. An avalanchel
Whilst filming a TV programme, expert skier Nic Farquit was caught
in one of cold's most frightening killers.
Came up for one breath, then engulfed again.
Then hitting the snow at the bottom
and the rest of the avalanche pounding me down like a hammer.
He was lucky to survive, but each year many hundreds don't.
Snowfalls usually build up to strongly bonded layers,
but sometimes one layer remains weak.
Even the vibrations from a skier can cause the layer above to slide off.
In seconds, hundreds of thousands of tons of snow hurtle down
at speeds of over 100 mph.
With so many visiting ski resorts each year,
avalanches are a real threat.
Dedicated teams of avalanchers battle against the weather.
They seek out potentially dangerous build-ups
and overhangs of snow... and dynamite them.
Sometimes, the unpredictability of the weather can catch us all by surprise.
The little town of Galtur should have been safe from the threat of avalanches,
but a freak combination of weather systems
made it the victim of one of the deadliest in the Alps for years.
It had been snowing heavily for several days
and deep snow was piling up on the mountain above Galtur.
High winds changed direction, lifting more snow on top of it.
No one knew that underneath this huge mass of new snow
was an unstable layer.
A few days of warm weather
had previously melted the surface, which had turned to ice.
The new snowfall couldn't bond to this hard icy layer.
No one knows exactly what triggered it,
but in seconds, over a third of a million tons of snow
tore down the mountain at a devastating 186 mph.
This monster wiped out everything in its path
and the town of Galtur was crushed under its weight.
38 people died.
It was the worst disaster for 30 years.
Here in the mountains, the weather has one more trick.
The snow that brings the devastation of avalanches
also creates cold's most enduring monument, a glacier.
We've to go along the white ice to the green ice up here,
the glacier... a long way still.
Mountain guide Russel Brice is going to take me
to the source of the Argentier,
one of the most impressive glaciers in the Alps.
To understand how it forms and what it does to the weather,
we have to climb it.
Down here at the base, it seemed like a good idea!
The glacier has been here for over 10,000 years.
It takes the ice 500 years to travel from the top to down here.
Way above us lies the source of this stream of ice.
Surprisingly, it starts its life as snow.
Over time, the crystals bond together to form the ice.
As it falls, year after year, the layers of snow become crushed
into little ice crystals that fuse together.
The weight of the new snow compresses the ice below even more,
eventually turning it to pure blue, glacier ice.
When the glacier is big enough, it starts to move
and, over thousands of years, a vast river of ice is formed.
As it flows, it breaks into enormous crevasses.
The glacier is over six miles long and two miles wide.
It's amazing in here. It's going to be quite hard to get out.
- "Look how hard the ice is. " - Extraordinary.
It will shatter. See how it's cracked all round here.
- How do you get a grip? - "It's what we have to do. "
What is it that makes this so smooth with all these layers?
The sheer weight of the ice on top of itself.
If you take a handful of snow and squeeze it and squeeze it
really hard, you'll make ice.
The amount of pressure that created that, the pressure!
How are we going to climb that?
Quite hard ice here.
It's quite delicate, isn't it?
Climbing!
- Remove slack! - "Sorry. "
Y"eah, that's good. "
It seems impossible to get a grip. "K"eep me tight.
Y"ou can get your axe in there. "
- Ah! - "OK?"
- "How you doing?" - All right.
- "Just to the left, there. " - Yeah.
- Oh, what a relief. - Y"eah. "
- "Excellent. That's good. " - Not very graceful.
Every 100 metres up, the temperature drops by half a degree.
It's the mix between the cold air up here and the warm air
blown into the mountains from below
that can make the weather so ferocious.
It's also what creates the snow which makes the glacier.
Finally, the peak of the mountain,
where it all begins.
Here we are, the old Holy Grail.
See here? This is the collection area.
This is what collects all the ice and snow,
where a glacier would actually start.
This is truly the most spectacular sight I've seen
in all my work on this programme.
It's also one of the coldest and most terrifying sights.
Those crevasses, how big and deep are they?
- "Maybe 50 metres deep. " - 50 metres deep!
- If somebody's down there? - "Not a chance, you die. For sure. "
Just a staggering landscape.
This landscape is changing.
Across the whole Alps, almost half the ice has melted.
100 glaciers have disappeared, all in the last 150 years.
Why? Global warming.
If it continues, by the year 2050, ice cover will be 20 per cent
of what it was a century and a half ago.
All across the world, the story is the same.
From the Andes to the Himalayas, glaciers are on the retreat,
melting faster than the snows can replenish them.
But the real problem is here at the poles.
If the ice north and south, including the glaciers, all melted,
the sea level would rise by 20 feet,
submerging low-lying cities like London, New York and Tokyo.
The irony is that cold, our greatest enemy,
is also preserving the world as we know it.
Back up north in winter's lair, my journey is at an end.
I've learned to respect nature's most powerful weapon.
I've seen the devastation cold brings, in all its forms,
ice, snow and freezing rain.
And I've seen how powerless we are against it.
Like all weather, winter and the cold that it brings
is uncontrollable and unpredictable.
We must learn to live with it and prepare for its very worst.
I will never take cold for granted again.
In the next programme,
I'll follow the violent journey heat takes
from the steaming jungles of the equator...
through the blinding heat of the deserts...
and on into an uncertain future.
Our world is warming up and our weather is getting wilder.
I'll try and find out what the future holds.
My God!