Original subtitles

We live on a crowded planet.

But there are still vast areas...

ELEPHANT TRUMPETS ..where nature has the upper hand.

It looks like another planet.

I'm heading to the last great wildernesses.

I'll try to cross four of these rugged landscapes...

Oh, my God!

..on my toughest journeys yet.

I have to be honest, things are not going brilliantly.

A bit of a medical situation.

Help is a long way away.

- Well done. - Well done.

- SIMON LAUGHS

I want to meet the people for whom the wilderness is home...

Testicles for breakfast, lunch and dinner!

..to see how they live alongside nature.

Whoa!

I can stay down there for a minute or so.

He's still down there now walking around.

And in this critical time for our world...

Huge carcasses of great trees.

..seek out the rare and majestic creatures that still survive...

My heart is racing.

THUNDER

..in some of the most hostile environments...

Are you OK, Jonathan? - Yeah, yeah.

- ..and the remotest regions... Bloody hell!

..of our wild planet.

Big cats roaming free.

This surely is the absolute definition of a real wilderness.

I'm in Argentina, travelling through Patagonia,

a region so vast it covers the lower third

of the continent of South America.

It's a land of myth and mystery,

of grasslands and forests surrounding mountains and ice.

Nature is still in charge here,

in one of the wildest places left on Earth.

Oh, my God.

I mean, it is breathtakingly beautiful, isn't it?

Our plan is to head that way -

the end of the valley and then up,

because up there, beyond the mountains,

is a vast store of ice.

The South Patagonian Ice Field.

The ice field is the cold heart at the centre of Patagonia.

It's a colossal critical bank of frozen water.

I don't think we know enough about it.

I hope to reach it, then track it right down to its southern edge.

On the journey I'll try to meet up with some of the rugged souls

who survive in wild Patagonia.

Across the huge grassland steppe of Eastern Chile,

I'll search for pumas - the mountain lions of South America.

Ultimately, I hope to reach the Grey Glacier

in the south of the ice field.

The first challenge is getting to the South Patagonian Ice Field,

high above us.

It's hard to reach. - Yes, it's dangerous.

If you will see the blue sky now, it's perfect,

but we have to see what happens at the end

because we are going in that direction and we have to see

what's happening with the clouds coming from the Pacific Ocean.

- So, fingers crossed, we won't get stopped by the weather.

Ceci Vedelago is an Argentinian guide.

She has more than 20 years of experience climbing

the Andes Mountains that run north to south down through Patagonia.

- You see there, the glacier? - Yeah. - We're through that valley,

and we're going there to get to the middle of the ice field.

We need three days to get there.

In some parts it will be a rocky area - that will be a challenge.

In some parts we have to cross the river - a challenge.

We cross crevasse - that will be a challenge.

- You've used the word "challenge" several times, Ceci.

- Yes, exactly, you're right. - Flippin' 'eck.

Our journey to the ice field will involve climbing, hiking

and freezing wading.

Oh, my God! - Oh, it's not that bad. - Oh, yes, it is.

Oh, my God!

Along with Ceci and me on the expedition,

there's a small TV crew and climbers guiding us up to the ice field,

including mountain rescue experts with advanced medical training

in case of emergencies.

It can be so brutally cold up here.

The best time of the year to be here, trekking,

is December to March. It's now May.

There are no resupply options here.

There is no mobile phone service.

If one of us gets injured, a rescue would be a bit tricky, in truth.

This is a remote and rarely visited corner of the Andes Mountains.

Day one of our expedition is a long trek with heavy packs.

Eventually, we reach a site where we can camp for the night

as temperatures start dropping towards minus ten.

So we've set up camp and the priority now

is to get warm, get some food inside us and get to bed.

I've got to switch boots now from trekking boots...

..to class B2 mountaineering boots

because...we're going up.

Ahead, I start to catch glimpses of the mountains

which guard the great ice field that sprawls beyond.

- Stay by yourself, especially the first 15 minutes.

- We're following a jagged, barren valley

carved by the force of enormous ancient glaciers.

Their crushing ice crawling and grinding down the mountains.

Above us, silent and brooding, sits the South Patagonian Ice Field.

It's a vast geographical feature of the planet,

helping to regulate the entire ecosystem of the continent.

I'm really hoping we can get up there

to get a sense of how the ice field still fares in our warming world.

So, we need to get across this.

Lucas Jacobson is our expedition leader.

He's securing a line to get us across the gully.

A true mountain man,

Lucas has scaled some of the highest peaks of the Andes.

- Hey, Simon, we have the zipline here to cross.

Basically, you, Simon, need to pull yourself. - OK.

- We should have contact all the time. - Right. - Perfect.

- I hate heights.

- OK? - Yeah.

- Your hands behind your head and pull it slowly. - OK.

Oh, my God.

Thank you.

OK?

So this torrent of water is all coming off

the ice field that is above us.

This mass of ice up there.

Above is the largest expanse of ice in the Southern Hemisphere

outside Antarctica.

These melt waters sustain life across the Patagonian wilderness

and beyond.

And now I can start to see the ice field above.

Up there.

That is what we're heading towards.

It's still a bit of a distance.

We think it'll still take at least another full day's climb

to get up to the ice field, but the weather is closing in on us.

The wind is...

It's so powerful here.

Sometimes I take the classic two steps forward

and get blown one step back.

- Simon, welcome to Patagonia!

- THEY LAUGH

Rain alternating with sub-zero blasts of wind

makes the bare rock surfaces icy and treacherous.

It's not long before we have our first casualty.

It's our cameraman Piers.

- I just twisted my ankle.

- Piers, you all right? - Yeah, yeah.

Just give me a minute.

- I'm quite worried about Piers, our cameraman.

I don't know if he's going to be able to go on.

We find a sheltered area among boulders

where we can camp and discuss options.

How is it feeling, mate?

- It feels a bit swollen. - Right.

- The problem is, there's still a lot more up to do

and the up is, erm...is the problem.

- To be honest, as you see today, the rain, it's getting more

and more technical every... every metre we're moving.

If anyone needs to be rescued,

it involves, like, in between 30 and 40 people.

- What, to evacuate a person? - Yeah.

So, because you're still in a condition to walk by yourself,

I decide that tomorrow is a good day for you to return

to the last camp and start to make your return all the way back.

- All right, mate. Well, it's crap, but it's better you go out safely.

- Yeah. I'll have to show Chris how to use a camera!

- Look, we've got the badger out.

- We'll get some audio, at least! - CHRIS LAUGHS

Fingers crossed.

The glaciers here very kindly left a whole load of...

stones lying around as they retreated.

Hopefully now, I will not be taking off in the night.

WIND HOWLS

I'm just blowing up my mattress.

You need an inflatable mattress here

because you've got to get your body off the cold stony ground.

I have to be honest, things are not going brilliantly.

We've had an injury and we've just heard that there's a storm coming.

And the storm might mean that we will not make it to the ice field.

We're going to have to see what the weather is like in the morning

and we'll make a decision on whether we go up...

..or whether we go down.

WIND HOWLS, TENTS FLUTTER

For hour after hour, we're lashed by a Patagonian storm.

The wind is really going for it now.

It's a little bit scary, to be honest.

I'm not entirely convinced this tent is going to hold.

Clear skies.

A huge relief.

But another, bigger storm is forecast.

So if we're going to make it to the ice field, we need to go now.

We're up at first light to make the final and most challenging ascent.

- We're very close to the Patagonian Ice Field.

With a blue sky, some cloud is passing.

Perfect timing.

- As we climb up the valley, we map out various routes ahead.

But several are blocked by thick ice and rock falls.

It means we need to take another way up.

- One possible route is going on the right, into that gully there,

but we can't figure it out now. There's a lot of ice. - OK.

- So, the other Plan B route is up here...

..with some fixing ropes. - Ropes? - Yeah, ropes. - OK.

We've got to get up.

My full rucksack weighs more than 20kg.

Tricky on a narrow ledge.

Bloody hell!

So we're nearly up at the snow and ice line now.

Nearly.

Here we go. Look.

This little channel, to me, feels like we're crossing

from the land of rock to the land of ice.

As if to prove a point.

After several gruelling days,

finally we've reached the edge of the South Patagonian Ice Field.

It's an enormous wall...

of snow and ice.

To get up onto the ice field to see its true scale,

we now need to climb up a 40 degree slope of sheet ice for miles.

One slip could send us sliding down hundreds of feet onto jagged rocks.

That could easily be fatal,

so we're wearing sharp crampons on our feet to give grip.

- OK? - That's good. Yeah, that's good.

And we're roped together to save us from a slide

and from falling into a bottomless crevasse

that can suddenly appear under your feet.

- BLEEP!

- We haven't really got much time for rest stops...

..because a storm is coming...

and we've got to get off the ice field.

We don't want to be stuck up here for too long.

So we've got to move as quickly as we can, but...

Argh!

I've just put my foot into the edge of just a little crevasse.

I can't see the bottom. Ooh-ha-ha!

For hours, we trek upwards.

I'm properly shattered.

I'm starting to feel like we'll never reach the top -

the ice field plateau.

Then, eventually, suddenly, the ice levels out.

We've made it.

This...

is the South Patagonia Ice Field.

Oh, my goodness.

- Yesterday, it was raining, and now look here.

A blue sky, the sun, we can see all the summits,

all the mountains, right in the middle to the ice field.

- The mountains here are the middle of the ice field?

- Correct, yeah. - Yeah. - That's unbelievable.

Still you have more ice field in the back. - Wow.

You have no idea how big it is up here.

It's enormous. It's on a scale that I just...

I couldn't comprehend.

Stretching more than 200 miles north to south,

billions of tonnes of frozen water.

The South Patagonia Ice Field covers more than 5,000 square miles.

In some parts the ice is a mile deep.

HE WHISPERS: Silence.

On a very busy planet...

..this is a proper wild...

wilderness part of the world.

- It's unique, this place.

- For me, being here, makes me, like, in real contact with the land,

with the natural areas.

- I feel... I feel emotional being here.

What an absolutely staggering part of the planet.

Look at this.

So, thank you, guys.

- Well done. - Well done.

- Getting onto the ice field, seeing the scale of it,

feels like a real achievement.

From here, I'm going to head south,

exploring more of the wilderness in Patagonia,

trying to get a sense of how this whole region is coping

as our world heats up.

This is one of the least explored mountain areas of the world.

It's one of the least known ice fields on the planet.

But it is vast.

And the store of fresh water here

is vital not just to Patagonia

but to the whole of South America,

and the impact of this vast store of ice

is felt by the climate across the region

and helps to regulate the climate of the world, no less.

Of course it does.

Every little aspect of the planet helps to keep it in balance...

..and this here plays a crucial role.

If this wasn't here, if this was the colour of the rocks around...

..it would absorb more of the sun's energy and heat

and that would further drive planetary climate change

and global warming.

We need this ice field. All of us do.

It matters to everyone.

With the weather about to turn and a powerful storm on the way,

we start the long trek down from the ice field.

I want to head south through the foothills of the Andes...

..to try and meet some of the people who live on the edge

of this frozen wilderness and perhaps understand it best.

Trekking down the ice wall into the valley

pulls and strains a whole new set of muscles.

But our packs are lighter, nobody snaps an ankle,

and after two days we find ourselves off the ice and hiking through

some of Patagonia's mind-boggling range of landscapes.

Soon, we're in bleak and windswept forests and grasslands.

It's romantically rugged.

Miles to the south, we pick up our four-wheel drives.

It takes a tough and hardy soul to survive out here year round.

But Argentina's gauchos farm this area

and we're heading to a remote gaucho outpost.

Lucas is taking me to meet some gauchos -

the legendary cowboys of South America.

They live much of their lives on horseback.

Probably wise, considering the state of the roads.

Great stuff. Well done.

A little bit stuck.

Being in the wilderness, travelling in the wilderness, is tricky.

We're not here alone. We've got another...

Some of our team are in a vehicle behind.

We're going to have to bring that up and try and pull this one out.

The sun is going down, we're still about four miles

from our destination, which is not ideal because we keep getting stuck.

We really need to make it there tonight.

This is as far as we can go on four wheels.

We have to do the last section on foot.

- Simon, we are almost there.

- There it is!

God, it's a tiny little thing.

DOGS BARK

- Hey, buddy. - Look at this place.

Thank you, mate.

Taibo lives out here alone in the wild for months on end,

with only his dogs for company,

looking after herds of sheep and cattle.

His friend, Juani, another local gaucho, is staying for a few nights.

Wow.

Well, this place is very... very special.

LAUGHTER Several bottles of wine.

- Taibo sleeps here and he spends most of the summer here.

- How long have you been a gaucho, Taibo?

So that's in your bones.

We'll be staying with Taibo and Juani for two nights.

We'll all fit into a single basic room.

OK.

It's cosy. - It's cosy, eh?

- Yeah, there is space for all of us, I think.

So, we've got somewhere to stay, we've got somewhere to sleep,

we've got some food to eat, hopefully.

- Oh, we're fine. We'll survive.

- What a life this is, eh?

Yeah, there were some gauchos until pretty recently,

they would spend something like a year in a lonely outpost like this

and not see another human being.

There is something remarkable about that existence.

Something that's still quite appealing.

Intimidating but appealing, out here in the wilderness.

DOGS BARK

Oh!

I slept OK. Well, not too bad, anyway.

But ironically, after worrying about everybody else snoring,

apparently it was me snoring for Britain.

Yes, a few too many glasses of the red wine, I fear.

Taibo is already up, cooking breakfast.

This far south and with winter approaching, days are short.

Taibo spends most of his time working outside in the elements.

He has to endure Patagonia's brutal winds and temperatures

that range from minus 20 in winter to more than 25 degrees in summer.

A hearty breakfast is essential.

Mm! That is an exceptional breakfast.

- Basically, there's beef for breakfast,

lunch, dinner...

The same. - Repeat. - Repeat, yeah.

Or lunch can be...

You know, in Argentina, we eat also... Do you know cottage pie?

- Cottage pie? - Yeah. - Yeah. - It's very popular in Argentina. - Mm-hm.

I wasn't expecting you to say that, but, yeah.

Mm-hm.

SIMON LAUGHS

I love that.

Yes. Are you a particular fan of mashed potato?

- Mashed potato with meat.

- Cut off from the rest of the planet,

Taibo stays out here with few of the benefits of the modern world

and less of the headaches.

His tools are his sheepdog, a lasso, and of course a sturdy horse.

- This is going to be your horse. Valencio. Super calm.

For everybody. - I appreciate that.

Gauchos are legendary riders. Me, definitely not so much.

And they have their own riding style here.

- There you go. You pull your hand left.

Exactly. - OK.

- That's left. Right, the other way.

- And to stop? - Just pull back. - Just pull back. - And then release.

- The gauchos, the landscape, the wilderness.

Gauchos have lived like this for generations.

Ranchers first came here in the 19th century.

Over the years, they've encroached ever further into the wilderness.

- Brr-brr-brro!

You move them from the left. - OK. - Yeah?

- Their sheep and cattle graze the land.

Sometimes overgraze it.

And the fences they put up do cause problems for the wildlife here.

But their way of life is still at the mercy of the environment

and the landscape.

- Very good.

- The climate of Patagonia is governed by the Andes Mountains

and the enormous ice field that sits above us.

My God.

It looks like another planet. Look at the colour.

Taibo has lived out here on and off for his whole life.

I wondered if he'd seen changes in that time.

I know Patagonia is one of the wettest

and windiest places in the world...

..but how has the... how has the weather changed here over the years?

I mean, for me, that's... that's a scary thing that you're saying.

You're talking about dramatic changes in a short period

of time that you are personally seeing with your own eyes.

- Ya!

- Taibo knows these wild mountains.

He's not a scientist monitoring from afar, he's a witness.

A canary in a coalmine alerting us to profound change

in this wilderness.

The ice field is shrinking, rainfall has dropped,

there's drought, forest fires increase.

This is the climatic upheaval we know is made more likely

and extreme by our global climate crisis.

I'm getting a little bit sore...

..in places that you don't need to know anything more about.

Juani wasn't born to the gaucho lifestyle.

He actually grew up in a town.

But he's chosen this way of life,

living out on the raw edge of the wilderness.

There aren't many younger men here like him.

- Gauchos, I think, they have this passion,

but it's really hard for other people to do what these guys do.

Where you have to work to take the cattle from the mountain...

Not the top.

But all the cattle down. - Mm. - That is a mountains crew.

Now, the problem, this generation, people of my age and younger,

they're not staying on the farms any more.

They prefer to stay in the city.

- And there is a risk that the gaucho... - Yeah.

- ..the way of life might wither and die out?

- Erm, yeah.

- The gaucho life is a solitary one, but obviously, there are upsides.

It's quite delicate. - Yeah?

- The texture is like a hard boiled but perfectly cooked egg.

And it's a very light meaty taste.

- Testicles are great.

When you're doing all the work with the cattle...

You know, the castration. - Yeah.

- Right after that, you put all the testicles in the bucket

and the following days they are eating testicles.

- Testicles for breakfast, lunch and dinner.

Go on, all in, then. A bit of intestines.

This is... This is very good.

Does anyone just want to go and talk to the dog?

- It could be a puma.

A fox, a puma.

- Hold on, did you just say it could be a puma?

- Probably. - Probably?!

Is that one of the biggest threats to a gaucho's flock or herd?

- Of course, when they are about one year old, one year and a half,

they are still a prey of a puma. - Right, a foal. OK.

- Yeah. So you have to really take care of them.

Keep them in the corral every night before evening.

Two years ago, a puma took down two foals.

One night we forgot them outside.

One night. And they were gone. - And the puma took them both? - Yeah.

- Charles Darwin wrote about gauchos in the 1830s

and he said they were very courteous, very hospitable,

full of modesty when talking about themselves or their country,

but also daring and brave.

I think there is still a great romance about the gaucho...

..and coming here, I think I can see why.

What an epic landscape and world in which to operate.

We're up early the next morning.

It's time to leave.

So, farewell to new friends Juani and Taibo.

Taibo, big hug, man.

God bless you.

Thank you. Stay safe.

To explore more of this beautiful wilderness area,

we're going to try and track along the Andes Mountains

and cross the border from Argentina into Chile.

We're about to arrive at a very remote border crossing.

I'm tracking around the edge of the South Patagonia Ice Field,

towards the mighty glacier which flows down from its southern tip.

This stage of my journey is taking me across

the vast Patagonian Steppe -

thousands and thousands of square miles of grassland

in the foothills of the Andes.

Across the border, the landscape of eastern Chile

is majestic and imposing.

It's here that I'm hoping to catch a glimpse of the big cats

of this wilderness.

I'm going in search of pumas.

Oh, man, it is spectacular here.

It's so vast, though. You could hide an army out here.

I need a guide who knows and loves this wild area.

We've found just the guy - his name is Vicente Montero.

- This is the right place to enjoy wilderness, man.

- Like many young men, Vicente wanted meaning in life

when he came here to the wilderness.

- I'm from Santiago, the capital of Chile.

A big city. You know, like, 9 million people living there.

And I was raised to stay there, you know,

and be someone according to my own family's preferences.

- And then you find here.

- I quit everything and came here to starve to death,

according to them. You know, like... - To your family? - Yeah.

I found, like, a purpose.

Or I really felt alive every single moment you're up here.

I mean, look at your surroundings.

- Look at that view. That is absolutely gobsmacking.

- The amount of fauna you can see here, it's...

it's unbelievable.

There are flamingos, there's skunks, foxes.

The condor here is three metres, 45 centimetres wide.

In the rest of Chile, they are only three metres.

- Vicente has spent more than a decade in Patagonia's mountains

and grasslands studying and helping to protect

the extraordinary wildlife that lives here.

- Right there.

- Oh, yes!

So, these are guanacos, is that right?

- Guanacos, yeah.

- And are they... Are they related to llamas?

- Yes, it's the ancestral animal that colonise all the Andes.

A guanaco, after 4,000 years of domestication,

then it borns a llama, which is like...

a lazy guanaco with long hair, you know.

A completely domesticated animal.

- You're being very rude about the llamas, but...

- Yeah, I like the wild version.

Their main defence mechanism, they sit with the wind

so they can smell everything that the wind brings,

and they look the other way.

So, if it's visible, they will make an alarm,

and what they can't see, on a bad day, they will smell it.

- So they've got both their bases covered? - Absolutely.

- Wherever guanacos are grazing,

it's possible predators could be nearby.

Pumas.

So, it's thought that there might be 50 to 100 pumas in this area.

They are South America's most iconic

but also elusive big cat.

Vicente has tracked and studied pumas for years.

If anyone can find them, it's him.

But pumas are pretty adept at blending into the landscape.

For hours, I just spot what Vicente calls PSRs -

puma shaped rocks.

So, the rain is just starting.

We're going to try and find shelter and then head out again tomorrow.

So, we're out before dawn...

and Vicente is using a thermal spotting scope

which picks out heat signatures in the landscape,

so he can spot warm-blooded creatures moving across the hills.

- But it only works before the sun comes out.

After that, the sun starts heating every rock,

and then I have, like, living things everywhere. - Yeah.

- So we only have a few minutes. We should get on top...

- All right, mate. - ..to keep scanning. - Let's go. - OK.

One of the sentinels is facing that way.

- Oh, yes!

- So, in this hill, in front... - Like a sentry.

- Always. It's the way they keep alive. - Mm.

- A little bit lucky.

There is something over there.

I guess I see the back of a puma.

Don't get excited yet.

- Why not? It's exciting. It's an exciting thing to do.

- Cos we're, like, 1km away, so let me be sure.

- So, what? You use the spotting scope to identify the heat...

..the binocular to check and the camera to confirm?

- Exactly.

Ah-ha.

There it is. Now let's go and check. - OK. - We can move.

- HE WHISPERS: - Right there.

- Oh, my God.

That looks like a lot of body of puma for one single puma.

- I think there are two. There are two pumas.

- I think I just saw a puma put its arm...

put its leg over the other one.

- Oh, now I see the head of the cub.

It's a tiny cub of, like, four or five month old.

Count how many there are.

- Well, I can see two.

- Come on, move a little... - Hang on, hang on. - ..higher up.

Count the ears.

How many pairs of ears do you count?

- Oh, my God. There are three pumas.

- Three pumas. - Three together.

- Now, she already heard us, she already saw us,

and she's still comfortable.

- This is completely astonishing.

Three wild pumas.

Pumas are found almost the entire length of the Americas.

So they're found from Alaska, right down to here in southern Chile.

But they're found in a greater concentration

around here in Patagonia than anywhere else.

It's on the move. The cat is on the move.

Wild big cats roaming free.

This surely is the absolute definition of a real wilderness.

Pumas are also known as a mountain lion.

They're the apex predator supporting the entire ecosystem.

We've just found this carcass. Is it a guanaco?

- It is, and you can see all the grass around it,

how tall and different from the rest.

- It's very green here.

- All the nutrients go back into the ground

and that is the latest process, because before they feed

hundreds of different species, and I'm not being exaggerated, like.

The puma do the kill, eat as much as possible,

you know, but then they leave the carcass behind

and the next animal that comes is the condor.

If there is, for example, a fox also eating the rest,

the condor comes here, spread their wings,

the fox moves away and then the condor eats whatever they can.

After the condor comes the armadillo.

After the armadillo, also the skunk.

People usually don't associate the skunk as a carnivore, but they do,

and they take every tiny piece of fat or meat

that is left behind. - Wow.

- Then come all the scavengers.

So the puma is absolutely central to the ecosystem.

- Much of the Patagonian wilderness here

is a protected area called Torres del Paine.

It's been a huge conservation success.

Just a few decades ago it was rare to see pumas here.

Now there's thought to be several hundred in the region.

- There, there, there. There it is. - Just here.

- There, there, there, there.

- He's got it all as a cat and a carnivore.

- That's why it's the king, man.

It's the king of Patagonia.

Nobody messes with him.

- This wilderness is a long way from heavy industry and huge cities,

but the impact of humanity is still felt here.

Climate change and drought in Patagonia

is thought to be pushing guanacos further out of the mountains

in search of grazing.

Pumas follow the guanacos and that's bringing them

into conflict with ranchers who farm sheep at the edge of the wilderness.

- They always will prefer the guanaco,

but occasionally they do have a tasty lamb available

that's left the safety of the herd

and, well, the puma is an opportunist,

as most of apex predators, you know,

so if they see an opportunity, they hunt it.

So, what does the ranchers do?

They kill pumas even though they're protected.

The economic losses for them are so high

that they choose to ignore the law and still kill many pumas.

- Even here, pumas still face threats,

and they won't be immune from the great planetary changes

facing this wilderness.

The next years and decades will be crucial

for ensuring their future.

Condors.

This is the final part of my journey.

I've made it down close to the southern end

of the South Patagonian Ice Field.

I'm heading towards a glacier which flows slowly down from the ice -

the spectacular Grey Glacier.

Vicente, what a place this is.

- Beautiful. We were very lucky.

You can see how spectacular it is.

- Up there, at the top,

is the ice field from which this glacier flows.

It's been several weeks since I began my journey

up to the ice field.

I'm hoping that if I can reach the Grey Glacier,

I'll be able to understand how our changing climate

is impacting on this world of ice and rock.

- How are you doing? - Doing OK, mate.

It's a bit of a trek,

but eventually we make it up onto the top of the glacier.

Four miles wide, it's one of 53 glaciers

that creep down from the great South Patagonian Ice Field...

..eventually turning into rivers that flow to the ocean,

giving life to everything on their route

across the south of the Americas.

This landscape is astonishing.

The glacier here positively glows with light.

It's almost as if it's lit from within. Like it's luminous.

And it's disconcertingly noisy.

Of course, there's the howling wind, but there's also creaks

and cracks and moans and groans coming from the glacier.

It feels alive.

I've got my feet well apart here.

I've got my crampons in the ice.

The wind will not take me this time.

- You can't fight the wind, you play with the wind.

You can play against it.

- The glacier is so brutishly huge, so epic,

that it can appear eternal, unchanging.

But Vicente is another person who has witnessed

a rapid transformation of this landscape.

- When I first came here in 2005, you can barely see, erm,

the beginning of this big nunatak - this island.

And this is only in a few years, you know.

- A nunatak? - Nunatak. It means island of rock inside the glacier.

- Just 20 years ago, this rocky island was mostly buried in the ice.

Every year, the glacier is retreating 100 metres.

I've been seeing the impact our changing climate is having

on Patagonia, but the melting of our ice fields here, in Greenland,

Europe, Asia and elsewhere, is a slow-burn global disaster.

The rate at which glaciers are melting has nearly doubled

over the past 20 years.

That further destabilises the climate,

making our weather systems more unpredictable.

It's astonishing to think that when scientists flew over the ice field

in an area near here not so long ago,

the altitude at which their plane was flying

would have put them inside the ice just in the 1980s.

That is how much the ice has melted away.

It's not too late to preserve our last great wildernesses.

These raw, wild areas need protecting.

They're worth fighting for.

They're vital for ensuring we have a healthy planet

and they're important for us as humans as well.

They feed our souls.

What do you see when you look out here? what does it mean to you?

- I think it's the wild side of nature.

We forget we belong into the wilderness,

we belong into the ice glacier, forests and everything.

- There is that sense that people have forgotten

they are living creatures on an astonishing planet.

We've forgotten that these wildernesses exist

and we need a bit of it in our lives.

We need that sense that nature is raw and powerful...

and wonderful!

THEY LAUGH

Next time, in the region they call the Amazon of the seas...

..I meet the spear fishermen of the Coral Triangle.

He is an astonishing human being.

It's a voyage to a truly remote corner of our oceans.

So, we've got a bit of a problem.

Oh, - BLEEP. - So it's far.

When I say it's far, it's far.

- Not another boat, nor another ship.

Help is a long way away.