All language subtitles for B42762E16116971772EC855EDB70A2C4_eng

In this series, we have explored
the Earth's frozen frontiers.

We have celebrated the astonishing
variety of animals that are found there.

And revealed the extraordinary ways
by which they managed to survive.

At a time when our ice
caps are melting faster than

ever before. We will meet the

scientists and people who
are dedicating their lives to

protecting our frozen planet.
And striving to turn things

around while there is still
time to do so. It won't be easy,

but it's doable. It's crucial
that we try to understand what

the impact will be, not
just for the wildlife and

the people that live there,
but for you and for me.

We start our journey in the high Arctic
and the vast frozen expanse of Greenland.

This huge island is
blanketed by the largest

store of ice in the
Northern Hemisphere.

But now, it's shrinking.

Professor Alan Hubbard is
a glaciologist, and he's spent

over 30 years studying the
movement of ice along Greenland's

coastline. It is quite a

beast of a glacier. It's
just growling constantly.

Thundering in the background.

Oh, there we go, bit of activity.

Carving icebergs is a natural

process, but what we've seen
in the last 20 years is there's

been much more melt and much more
ice carving off, producing huge icebergs.

So it's quite an intimidating
place to be hanging out.

One thing in particular

has caused this increase
in melting and carving.

We put this weather station
here in 2010. ["Pomp and

Circumstance"] And the hottest
temperature was two days ago,

at 22.37 degrees centigrade.
That is very, very hot for Greenland.

As the ice falls into the ocean,
it raises sea levels globally.

These are now rising by an average

of four millimeters a year. A
quarter of that comes from the

Greenland ice sheet. And scientists fear
that this figure could increase rapidly.

To investigate, Alan has
traveled 70 miles inland to the top

of the ice sheet, where the
glaciers start their lives as

compacted snow more than a mile thick.

Here, the effects of a warming
climate are only too clear.

There are thousands of
these beautiful azure blue lakes

littered across the surface
of the ice sheet. The surface

has always melted in the
summer, but not on this scale.

And
Alan wants to know what effect

the increase in meltwater is
having on the ice sheet as a

whole. The sheer quantity of water

shifting through this system is crazy.

Powerful torrents of meltwater
are boring shafts, known as

moulins, into the ice sheet.
This is nuts. This is a moulin

actively being formed, a moulin in genesis.

As we speak, that water
is finding the path of least

resistance, sculpting this
shaft that's going deep into the

ice.

And here it is, just
toppling over a waterfall

edge and dropping
into the ice sheet.

But where is all this meltwater
going, and what impact is it

having on the structure of
the ice sheet? To find out, Alan

decides to climb inside a
dried-up moulin. I think I must be

15, 20 meters down here. I'm
going to go down a bit further.

It's a very narrow shaft here.
It's always been assumed that

the meltwater drains straight
down and out of the bottom of

the ice sheet. But what Alan
discovers is very different.

I can hear a big amount of
water moving in this system. And

the water is starting to
spread sideways, laterally, so

the drainage system is
obviously complex, it's interlinked.

These observations suggest
that the meltwater is branching

out in every direction, causing
this once-rigid structure to

destabilize.

It's a bit rotten.
Everything's rotting here.

The implications of this are frightening.

Alan believes that as the
ice sheet begins to thaw,

it's sliding towards the
ocean at a much faster rate.

And he's now confirmed that,
using time-lapse, photography.

The ice, the front, can be
moving in excess of 20 meters a

day, which is fast. That is a
huge quantity of ice straight

into the ocean. Some of
Greenland's glaciers are moving

three times faster today than
they were 30 years ago. As the

climate's warming, the rate
at which this ice sheet flows is

absolutely critical. So whereas
at the moment we're thinking

this thing is going to take
thousands of years of melt and

disintegrate, if it does
move faster and accelerate, it

means centuries.

That is a really contentious
and very important question,

because this ice sheet has
enough water in it to raise

global sea level by over seven meters,
and that's a total disaster for humanity.

Calculations predict that
nearly half a billion people

living in coastal communities
around the world will be

displaced by flooding by the
end of the century. But if the

Greenland ice sheet slips
into the ocean more rapidly, this

could all happen far sooner.

Greenland isn't the only
large body of ice in the Arctic. In

winter, the ocean here freezes
over, creating a cover of ice

larger than the entire United States.

This sea ice has
always got smaller in

summer, but today it's
rapidly disappearing.

Hotter temperatures are melting
it at an unprecedented rate,

with worrying consequences
for the wildlife that depends on it.

For half seals, the sea ice is an excellent
place for giving birth out of the water.

It provides the defenseless
newborn pups with a safe space

for their first six weeks until
they're big enough to swim

proficiently.

But with the sea ice
disappearing increasingly fast,

will they be able to adapt?

In Canada's Gulf of St. Lawrence, a group
of seal biologists are trying to find out.

But the fragile sea ice is a
challenging place in which to work.

Go a little further out. To
support a two-ton helicopter,

the ice must be at least 30
centimeters thick, and the only

way to find out if that's so is with a

seal. The team are trying to
discover where the seals go

when they become independent.
So this is a juvenile harp

seal, which is exactly what
we've been out on the ice trying

to find a little ago. They're
absolutely beautiful. We'll be

putting a satellite transmitter
on the top of this animal's

head so that every time the
animal comes to the surface we

can get a location estimate
for where he is at sea. It

won't harm them in any way,
and in return the amount of

information we get from them is invaluable.

It'll be really interesting to
see where these animals go

as the ice starts to break up
over the coming months. The

results from the study so
far do not look encouraging.

Despite migrating huge
distances, when the time comes to

have pups of their own,
harp seals almost always

return to the area where
they themselves were born.

But as the sea ice shrinks, so
does its suitability as a nursery.

The problem really comes
about if the only ice available in

the traditional areas is
very thin. They'll still use that

ice and then you get increased mortality.

In short, the pups risk
drowning if the ice isn't thick

enough. And the bigger
question is, will the ice continue to

exist at all?

In my lifetime, we've lost about two-thirds
of the summer sea ice in the Arctic.

And it's likely that in the next
30 years we're going to end

up with an ice-free Arctic in
the summer. I think one of the

issues with climate change
is that it's really difficult

to see. But in the case of
harp seals, it's really quite

simple.

If we lose the sea ice in the
Arctic, we lose the harp seals.

For harp seals, their future,
it has to be said, appears

uncertain. But what about
the most famous face of climate

change, the polar bear?

Can this keenly intelligent animal
adapt to a rapidly changing world?

As the summer sea
ice melts away, many

polar bears are forced
to head for dry land.

Some swim up to 400 miles to get there.

This is Wrangell, a remote
island in Arctic Russia.

Wrangell is a unique
place. Bears are part of this

landscape. It's not suitable
for all of people. If I'm a

ranger, I like this life.

Without the sea ice, the hungry
bears cannot hunt seals and

feed on their calorie-rich
flesh, but find other sources of

food, including human food supplies.

This is an invention against polar bears.

I need to be prepared
against their invasions.

Each summer, Gennady
is joined by polar bear

expert Dr. Erik Reger.
We need to cross that ridge.

Erik wants to find out just how
many bears are ending up here.

In 20 years of studying
polar bears, I've never been

anywhere like Wrangell
Island. The density of bears is

unlike anything I've ever seen
before. This past two years,

we've seen about 500
bears. My sense is that's just a

fraction of how many are here.

But with so many hungry animals in one
place, is there enough food to go round?

Gennady, if you can keep an
eye out for us, please, like up

on the hill or just wherever
you got a good view. All right,

thank you.

This is a hairtrap, so bears
like anything that smells

strong, and so this has a
little bit of spoiled cheese,

milk, and fish in it. So the
goal here is to get a polar

bear to come in and put its
hand or its head inside this

box, and when that happens,
these little wire brushes will

pull out a few pieces of hair
that we can use for scientific

analyses. You can learn a lot
about polar bears just from a

piece of their hair. We can
figure out which individual it

is, or you can get
information on what

they're eating. There
we go, hair collected.

Eric's molecular studies of
the polar bear's hair show that

the bears on Wrangel appear
to be finding enough food. But

with more and more bears coming here, will
there still be enough food to go round?

One of the main things we
expect to happen with sea ice loss

is changes in the movements
and the distribution of polar

bears. So polar bears are
going to appear in places they

never were before, and
they're going to disappear from

places that they were.

Some coastal towns in Siberia have
been overrun with up to 50 bears at a time.

They're desperate to eat
whatever they can. And in the city

of Norilsk, one female was
found an incredible 250 miles

away from the coast.

Lost and starving, she
was eventually rescued.

But many are not so lucky.

They are intelligent animals,
but there's simply no food on

land that could compare to
the seals that the bears eat on

the sea ice.

A future without polar bears
would be very sad, but the sea

ice is not just essential
for animals. It's a lifeline for

many of the four million people
who call the Arctic their home.

People here call themselves Inuit.

Alekasiak Perry lives in
Kanak on Greenland's west

coast, the most northern
Inuit town in the world.

For centuries, life here has
depended on the sea ice.

The dogs are the safest
way to travel on the sea ice.

Without the dogs, our ancestors
would have never survived.

Not only are dog sleds a
way to reach neighbouring

communities, which can be
over 100 miles away, but in a land

where no crops can grow,
traveling over the sea ice is a

vital route to food, fur and
livelihood. We rely on the sea

ice to hunt the seals, to make a living.

The way of hunting is who we
are and where we come from.

But the dwindling of the
sea ice is making this way of

life not only difficult, but
increasingly dangerous.

This year, the sea ice
has a lot of waterfalls, and

it's breaking off quite fast.

We trust our dogs.

Somehow we know when
they are on the thin ice.

So based up, we cannot travel.

Today, they must turn back.

It has become difficult to
be a hunter. The sea ice has

become too dangerous to
make enough money to live. For

Canach's 650 residents,
the loss of sea ice is the loss

of an entire way of life,
and it is creating an uncertain

future. When the sea ice is
gone, it will affect everything.

If the world is changing,
then we must change with

it. But with us, the change
has been going very fast.

And there's a reason for this
accelerating rate of change.

In the last 30 years, over
14 trillion tons of ice have

been lost from the Arctic,
creating a vicious cycle of ever

-increasing temperatures.

Normally, large areas of snow
and ice would act as a mirror,

reflecting up to 85% of the
sun's rays back into space. But

as the ice melts, the
great white mirror is being

replaced by the darkness
of the ice-free ocean.

The dark ocean absorbs the
sun's rays, so causing even more

ice to melt. Creating a
feedback loop that contributes to

further warming.

Because of this, the
Arctic is now warming more

than twice as fast as
the Earth as a whole.

That has far-reaching
consequences not just for the Arctic

Ocean, but for the vast frozen
lands that surround it. The

tundra.

In summer, the open tundra provides
refuge for great concentrations of life.

But today, its thick surface
soil, that has been deeply

frozen for thousands of years,
is thawing. And the pooling

water is creating millions of new lakes.

Here in Alaska, we've seen a 40%
increase in the lake area since the 80s.

Professor Katie Walter-Antony
has worked across Alaska and

Siberia, studying their lakes.
She is interested not so much

in the lakes themselves, but
in what is seeping out of them.

We are seeing a bright spot
in the satellite image that we

suspect is gas bubbling.

To identify the gas in these
bubbles, Katie must collect

some of it. I'm surrounded
by tiny bubbles that are rising.

Methane appears to be the dominant gas.

Methane is produced by the
decaying remains of prehistoric

plants and animals. As the
frozen soil beneath the lake

starts to thaw, it releases
stores of this potent greenhouse

gas, which is up to 30 times
more effective than carbon

dioxide when it comes to
trapping heat in the atmosphere and

accelerating global warming.
45 parts per million for these

tiny bubbles rising higher and
higher. Now it's going above

70. This is a huge amount of
methane. It could be a mega

-seap.

We are discovering more and
more of these methane mega

-seaps. It's streaming out and
entering into the atmosphere.

Methane can be seen escaping from lakes,

but it also rises from the
land wherever the frozen

soil, known as the
permafrost, begins to thaw.

And the arctic tundra is
thawing and collapsing at an

unprecedented rate. It's
concerning because permafrost, or

frozen ground, occupies
about a quarter of the northern

hemisphere land surface. As
permafrost thaws, even a small

fraction of that trapped methane escapes.

It will accelerate climate
warming, and you cannot reverse it.

It's clear that in the Arctic,
changes to permafrost on

the land and floating ice on
the sea will have far-reaching

consequences to the planet
as a whole. And there is

nowhere better to see the
extent of these global changes

than from space.

All of my life I've thought
about how this would feel to

gaze back on the planet with
my own eyes. NASA scientist

Jessica Mir has spent six
months in orbit. From the space

station, you have the planet
spinning beneath you, and

you're passing over it at
17,500 miles per hour. We are

going around the entire planet
every 90 minutes. So you can

begin to see larger scale
phenomena in ways that you just

can't experience on the ground.
And we can see the change in

these systems over time. We
cannot deny that we are having

an incredible effect on the
fate of our planet. And the

effect that we have as
humans on our planet, right there

actually, I'm looking down
at several fires. I'm not sure

where those are. Let's take a quick peek.

So right now we're flying over Europe and I
can see some fires over in that direction.

And that is of course
something that we have to

contend more and more
with as our climate changes.

As the Arctic warms, wildfires
are not only getting more

intense, but they're breaking
out in parts of the Northern

Hemisphere where they
have never occurred before.

Some scientists believe that
unusually warm air rising in

the Arctic is disturbing
high-altitude wind currents like

the polar jet stream. Once
disturbed, the jet stream

produces hotter and drier
conditions much further south.

All of these factors that
contribute to wildfires, the

temperature, the soil moisture,
the presence of trees and

shrubs and other fuel, have either strong
direct or indirect ties to climate change.

A warming Arctic may not only be
responsible for the outbreak of wildfires,

but it may also be
leading to extreme weather

conditions across the whole
of the Northern Hemisphere.

I've always cared so much
about the environment and known

that we all need to do our
part in protecting it. But after

seeing this view with my own
eyes, after seeing all of those

ecosystems from up here, it
really makes it resonate even

more loudly.

Outside the Arctic, there's
another frozen realm that

stretches across the world's
continents, a high mountain.

Home to an extraordinary array of species.

But here, too, there's a problem.

Across the world, mountain
glaciers, which have existed for

tens of thousands of years,
are shrinking and vanishing.

By the end of this century,
some ranges may have no ice

remaining at all. And this
will affect not just animals, but

people, too.

Ice lost from the mountain
glaciers, from the great ranges

of the world, have a huge
consequence for the populations

downstream. And that
consequence is their water supply.

Glaciers in the Himalayas
are the source of ten of the

largest rivers in Asia, which
together provide reliable

fresh water for around a
billion people downstream.

If the glaciers disappear, so,
too, will the water they supply.

We know that these glaciers
are losing about half a metre of

ice a year. What we don't
know is how much ice is left. So,

if we know how many metres
of ice are left, we can work out

how long they'll last. How
long this water supply will keep

going. Dr Hamish Pritchard
is part of a team of scientists

who have devised a new
instrument to measure ice. They

measure one of the largest
Himalayan glaciers. What we're

putting together here is a
long frame structure, and it's

designed to hang underneath
a helicopter. We're going to put

a radar on it, and the radar
will send out radio waves and

then bounce back off the
bottom of the glacier, and we'll be

able to measure how thick the
ice is. Once his team know how

thick the ice is, they can start
to work out how long it will last.

Yeah, today was the moment
we were just waiting for it to

get lifted up for the first
time. We're hoping it's going to

be nice, steady, stable, nice, easy
lift off, but we're about to find out.

Line is clear.

There's a lot of lifting.

Okay, Mike, we must north
of me, north of H.E.V. to the

Khunjung area. Hi, Dr Hamish
here. How's it flying? Yeah,

with the wind picks up, it's
a little more squirrely, but no

problems otherwise. Yeah, it
might want to go up a bit more.

We're going a little bit
of height there. Yeah, no

problem. Yeah, we'll fly
up the net towards Everest.

After hours of scanning,
the projection for

this particular glacier
is finally revealed.

Yeah, that's pretty nice
and clear. I can see exactly

how thick that ice is.
That's about 150 meters.

So at the current rate of
melting, this section would last

maybe two to three hundred
years. But we know that the melt

rates are increasing.

And this is one of the biggest
glaciers, so there are many,

many glaciers which are much
smaller than this. Much thinner

ice. And they're going to be
disappearing much, much earlier than that.

Water is already scarce in
parts of Asia. And as glacial

water supplies dry up, there
will be even less to go round.

So what happens if
these glaciers disappear?

Is that in dry summers, the
rivers dry up. Tensions rise,

especially between nations
as they share water across

borders.

So one of the big risks of losing this
ice is that it raises the risk of conflict.

And that's a frightening
prospect. If I have a one-year-old

son, children born at the
same time as him will see this

happen.

We need to act now to
turn those trajectories round.

There's no doubt that large
tracts of our frozen wilderness

are undergoing dramatic
changes. But what about the largest

body of ice of all? Antarctica.

We have already seen how
even here, animals live in the ice.

The living around the fringes
are starting to be affected by

climate change, including
chinstrap penguins.

But for another penguin, the Adelie, the
consequences are even more extreme.

I arrived here for the first time in 1974.

This part of the world was just

incomprehensibly wild.
It was filled with life.

Antarctica absolutely captured me.

Professor Bill Frazer
has dedicated his entire

45-year career to
studying the Adelie penguin.

What really fascinated me
was the incredible hardiness of

these penguins. Feisty,
determined, beautiful little animal.

But this environment is changing.

In the last 45 years, the
tremendous warming that has

occurred has had an incredible
impact. The changes have been

very rapid, more rapid
than anyone anticipated.

Bill has witnessed firsthand
how these changes have affected

one of the largest colonies
of Adelies on the western side

of the Antarctic Peninsula.
Four decades ago, this area

contained 20,000 adults.
Currently, we only have somewhere

in the order of 400,000 adults.
We have 100 breeding pairs.

One of the issues that
Adelies are clearly experiencing

right now is just the increase in rainfall.

Adelies are a creature of the
high Antarctic. They evolve in

a dry, cold polar system. They
simply cannot tolerate being

continuously wet.

The chicks are soaking.

The rain is penetrating
their down, breaking

down their ability to
insulate themselves.

That's why you see they're
shivering, because they're just

trying to maintain their body
temperature and they can't.

Sad.

This tiny chick at this point
has zero chances of surviving.

They can't even react to
the presence of a predator.

We are standing, looking
at climate change, actually

killing off these Adelie
penguins, one at a time.

Before he leaves Antarctica
for the last time, Bill is

visiting an island that was
once an Adelie paradise.

When we used to walk
onto this island, you could

immediately hear the
Adelies. They were everywhere.

In 1974, the populations here
were somewhere in the order of

a thousand breeding pairs.
All that remains are these little

pebbles scattered throughout
the area, stones that were used

in former nest sites. The
pebbles are still visible, they're

very abundant, but the
birds are gone. This is where

we recorded the first
island-wide extinction of Adelie

penguins.

And now the silence that
exists here is pretty overbearing.

There's no words that can really
describe what I'm feeling at the moment.

We're working with canaries
in the coal mine. The Adelie

penguins are, without a
doubt, indicator species that are

telling us that the globe is
changing, the globe is getting

warmer, it's happening, and
we need to do something about

it.

The disappearance of Adelie
penguins along the Antarctic

Peninsula is just one
example of how record warming

temperatures are affecting life here.

But warming temperatures
are also affecting the very

coastline itself. With serious
implications for global sea

levels...

Across the glaciological
community, we've identified that

sea level rise from Antarctica
is the most pressing question

for the next 50 to 100 years.
And we as a collaborative

group have come together
to try and understand it, and

governments have come
together to try and understand it

because it's important. Professor
Sridhar Anandakrishnan has

been working in the polar
regions for over three decades.

He's part of a team of
scientists undertaking the largest

Antarctic expedition for
more than 70 years. Their

destination is a remote part
of western Antarctica called

the Thwaites Ice Shelf.

Without getting out on the ice, you
can't measure things underneath the ice.

Those kinds of things can't
be done from space. They can't

be done by drones or aircraft
flying over it. You actually

have to go and put your
instruments on the ice.

The interior of Antarctica
is covered in a giant sheet of

ice, which for millennia has
been slowly flowing to the

coast.

But because it's so cold
here, rather than carve into the

sea, the ice continues to flow
out into the ocean, forming a

floating platform known as an ice shelf.

As an ice shelf grows, it begins
to act as a dam, preventing

more of the ice sheet behind
it from slipping into the sea.

And the Thwaites Ice Shelf holds
back a body of ice the size of Florida.

But scientists are concerned
that the ice shelf itself is

now at risk of melting. We're
going down through 600 meters

of ice. Once we drill the hole, I'm
going to put the explosive charge down.

Small seismic surveys...
Okay, firing the hole.

...help establish exactly
where to sink their robotic

underwater probe, which
the team hope will record the

temperature of the seawater
directly beneath the ice shelf.

Okay, Andy, ready to
descend. Try to go a little slower.

Okay. Coming up on 75
meters. 75 meters now.

425 meters. We've arrived
at the ice-ocean interface.

Early results are not encouraging.
Have we noticed a huge

change in the temperature?
Uh, yeah. It is warm water. Can

you see it melt? Like, what's
going on there? Because of

climate change, warmer seas
directly beneath the ice shelf

are melting it from below.
So it's no longer a question of

if this giant dam will disappear,
but when. When the vast

ice sheet behind it spills
into the ocean, it could have

catastrophic consequences
for global sea levels over the

coming centuries.

The amount of water
that Antarctica contains

that could go into
the ocean is so huge.

This is a global problem.
The oceans are all connected

together, so as soon as a
glacier puts water into the ocean,

it rises all over the world.

If sea levels rise as
predicted, by the year 2050, 150

million people could be
displaced from coastal areas.

And by 2070, cities including
Miami, New York, Shanghai

and Mumbai will be at
risk of serious flooding.

How much water will Antarctica
contribute to sea level rise?

The biggest wild cardinal of
that is how we as humans affect

climate.

Recently, at COP26, 120
nations came together in

an effort to limit global
warming to 1.5 degrees.

While a 1.5 degree rise
will still bring significant

changes with it, to some
extent, it will be a challenge. To

understand any chance of
saving what remains of our

frozen planet and saving
ourselves from the devastating

consequences of its loss, we
must stick to this commitment

and honor it no matter how
challenging it might be. We know

that climate change is happening.
We know the main driver of

climate change is human
activities, it's human emissions. As

a whole human species, we
are not recognizing the impact

that we're having and the
fact that we do need to do

something. But the important
thing is that I believe all

these processes are reversible.
If everybody can make the

effort of doing just one
thing, reducing their carbon

footprint. Consume less, think
about what we need, what we

really want. Think more sensibly
about the journeys we take,

about the food we eat, how
that's produced. Figure out a

lifestyle that is sustainable.

And we're right at the point
where we can generate all the

power that we need from
renewable sources like solar and

wind. To do that, you need
to really transform society as

a whole. We can speak to
our representatives to try and

reconsider energy policies.
If enough of us are educated

about the effects of carbon in
the atmosphere, even the most

poorly educated politician
will respond to what their

citizenry wants. The awareness
and the concern is greater

now than it ever has been.
So that gives us some hope. It

won't be easy, but it's
doable. If you can do something

about it, then do it.
Instead of just thinking about

it, if you can do something
about it, then do it.

We can do it. It's within our power
to do it. We can do it. We must do it.

Then there will be a future for the planet.

We can do it. We can

do it.