-Greenland is a remote frontier land dominated by ice.

It's raw, it's rugged, and this is the very essence of Greenland.

The biggest island on the planet is home to less than 60,000 people, and there are still indigenous communities living sustainably and surviving in one of the most extreme environments on Earth.

♪♪ ♪♪ It would be easy to think that this distant land of ice doesn't matter to you or I, but the future of Greenland will impact on us all.

If its entire ice sheet were to melt, global sea levels would rise by 7 meters.

♪♪ We're on a quest to travel to North Greenland, to the very end of the realm of man and beyond.

On the way, we will see stunning wildlife, where, in places, the abundance of life here is staggering.

♪♪ And we're going to find out how climate change is reshaping the lives of the people in this extraordinary landscape, where the land is constantly changing and affecting the whole planet and the very future of humanity.

♪♪ ♪♪ Greenland sits on top of the world between the Atlantic and Arctic oceans, and it's absolutely dominated by a vast ice sheet that covers 80% of the island.

♪♪ This ice has experienced record melting in the last few decades.

We want to find out how global warming is profoundly affecting the country's climate and what that means for the island's wildlife and its people.

♪♪ Greenland is the biggest island in the world.

It's over 2,500 kilometers from top to bottom.

Although it's been part of Denmark for several hundred years, it gained the right to self-rule in 2009.

♪♪ Its icy landscape makes it feel like we've stepped into another universe.

♪♪ Greenland's ice sheet is the second largest in the world.

It covers an area of about 1.7 million square kilometers.

It's one of the best places to see the impact of a warming climate.

In the winter, temperatures here can plummet below -40 degrees Celsius, and it's hard to get your mind around the immensity of the ice sheet.

In places, it can be up to 3 kilometers deep.

Entire mountain ranges can be underneath you.

♪♪ Every spring, the warming temperature triggers the surface of the ice below the snow line to melt.

And the ice has always melted in the summer.

What's changed is the ever-increasing rate at which it's happening.

♪♪ ♪♪ Just a few months ago, this would have been a continuous sheet of ice.

♪♪ But now look how quickly the ice has melted into rivers that carve out ice valleys, creating blue pools of water on the surface of the ice sheet.

♪♪ The Arctic is heating at a much faster rate than the rest of the planet, and this melting ice sheet is now the main factor swelling the Earth's oceans.

Greenland's ice sheet has become one of the benchmark measurements for the march of global warming.

On the ground, the ice melt is dramatic.

But to really understand the enormity of the ice sheet, you have to get up in the air.

♪♪ The epic scale of this sheet is incredible.

Snow has accumulated and built up over thousands of years.

Some of it is at least 100,000 years old.

As the snow falls, the ice compacts.

It slowly moves out to the coast, to the exterior.

You can see a continual stream of ice coming off the main sheet itself.

This is the ice fjord.

It's dynamic, it's ever-changing, and this vast ice fjord and the glacier behind it is retreating faster and faster than ever before.

And the faster the ice melts, the faster it loses the benefit of what climate-change scientists call the albedo effect.

That's where the very whiteness of the ice protects it by reflecting heat.

But blue pools of water absorb heat much more, and that means the more the ice melts, the more the melt escalates.

It's a runaway cycle that feeds into itself, ever increasing the melt of the ice.

♪♪ And there's a reason why we should all take this very seriously.

If the ice melts entirely, global sea levels would rise by 7 meters.

That would wipe out every major coastal city on Earth and affect about 2 billion people.

♪♪ Of course, the first people to be profoundly affected by the loss of ice are the people of Greenland themselves.

We want to see what this changing landscape means for them.

♪♪ As most of the country is uninhabitable, the vast majority of Greenlanders live in the fjords on the southwest coast, where the climate is milder.

We're starting our journey in the town of Ilulissat, 350 kilometers north of the Arctic Circle.

♪♪ Ilulissat is one of the sunniest, driest settlements in Greenland, and with just under 5,000 inhabitants, it's Greenland's third largest town.

♪♪ It's a charming place, and as you walk around the harbor, you can see the boats that are part of an age-old way of life.

Fishing is still one of Greenland's biggest income generators and the source of many people's livelihoods.

♪♪ Despite the lack of grass... [ Cheers and applause, whistle blows ] ...everyone loves football.

It's Greenland's national sport.

♪♪ There are several good restaurants in Ilulissat serving fresh local produce.

This is really a place where, if you want fresh food, you eat what the locals eat.

♪♪ The market by the harbor is the place where hunters and fishermen sell their catch.

Today's selection includes minke whale and seal meat.

There's kidney, blubber, and intestines.

Every part is used.

[ Saw buzzing ] And what can't be eaten also has a use.

♪♪ Here, local craftsmen still practice the ancient tradition of carving figures out of the bones of dead animals.

In Greenland's Inuit folklore, these are avenging monsters called tupilaks.

It's clear that hunting and fishing are integral parts of Greenlandic culture.

They're not just a way of life.

They're vital to the people's very survival.

So we're going to see where people go to find muskox, a key source of meat for the Inuit.

We're traveling south from Ilulissat to an area of a beautiful lake called Tasersuatsiaq.

♪♪ And what a surprising landscape!

It's warm, biodiverse, and it's green.

In fact, the whole reason Greenland is called "green land" is because back in the 10th century, this is the area where the Norseman Erik the Red landed when he was exiled from Iceland.

Some say he used the name as a marketing strategy to attract more settlers.

But here, finally, Greenland lives up to its name.

This vast glacial landscape might look empty, but this 500-square-kilometer area is actually home to 25,000 muskox.

They're big animals, but Greenland is simply enormous.

And, also, they've been hunted for hundreds and hundreds of years, so they're very shy and prone to running off when they see man.

To find them, We're really going to have to search.

♪♪ Surprisingly for Greenland, it's over 20° Celsius down here in the lowlands, so the muskox have probably headed to higher ground, where it's cooler.

♪♪ ♪♪ Finally, a muskox!

This is the biggest land herbivore alive today in Greenland.

And although they're called "ox," muskox are actually more closely related to sheep and goats than cows.

These shaggy survivors from the Ice Age are beautifully adapted for this part of the world.

In the spring and summer, the green tundra provides a feast of willow leaves, tussocks, grass shoots, and flowers to graze on, and in the winter, they'll use their excellent sense of smell to break the ice to rustle up a meal of sedge and lichen.

♪♪ The next day, it's time to get back on the road on our journey north.

We've returned to Ilulissat to take to the water.

We're heading to the harbor to find the boat we've charted, called the Kisaq.

This is the vessel that's going to take us north into the High Arctic.

The crew on this boat have years of experience negotiating Greenland's treacherous waters.

Even though it's summer, this could be a dangerous journey.

The Kisaq is an interesting vessel.

She was built in 1964 and has a wooden hull.

She's been plying these waters for the last 20 years, and she's going to be our home for the next three weeks.

We're undertaking a journey that's been a long time in the making, an ancient journey that's both exciting and dangerous.

Our plan is to go from Ilulissat right up the west coast of Greenland.

As we go further north, the towns will get smaller and smaller, more remote, and more inaccessible.

We aim to reach an area called Thule.

This is home to some of the most northern human settlements on Earth.

We want to find out why people live here and how they survive in this extreme climate and why this is the northernmost limit for our species.

♪♪ This ice fjord is so beautiful and became a UNESCO World Heritage Site in 2004.

♪♪ It's the birthplace of a massive collection of icebergs that have been carved from one of the most productive glaciers in the world.

♪♪ It's just impossible not to be awed by the beauty of the water and its creatures.

♪♪ This truly is the land of the midnight sun.

It's 1:00 in the morning right now, and it's like daylight.

♪♪ This glacier produces immense icebergs.

They can be hundreds of meters high with most of the ice below the water.

They just take your breath away.

♪♪ ♪♪ The Sermeq Kujalleq glacier produces 1/10 of all of Greenland's icebergs.

During the summer months, as the ice sheet melts, around 35 billion tons carve off into the fjord.

[ Banging ] As we approach the glacier, you can hear the movement of the ice.

[ Banging ] This glacier has been studied for over 250 years, and it's directly informed our modern understanding of climate change.

[ Rumbling ] The power behind the ice is remarkable, and the ice that's falling is certainly tens of thousands, maybe even hundreds of thousands of years old.

It's been locked up here on Greenland's huge ice sheet and only now reaching the coast and being released.

♪♪ Across the bay from all this beauty, on Disko Island is an abandoned mine with an important story to tell.

♪♪ ♪♪ It's ironic to think that the coal mined here has contributed directly to the melting of Greenland's ice sheet.

♪♪ ♪♪ ♪♪ It may look like a ghost town now, but from 1924 to 1972, the Danish government exploited the island's rich resources, employing over 1,000 Danes, Swedes, and Greenlanders.

♪♪ A whole infrastructure grew up around the mine.

By the 1960s, the mine was producing 40,000 tons of coal a year, and its football team was top of the National League.

But by the 1970s, the mine was controversially deemed economically unviable, and it was abandoned.

♪♪ Back in Disko Bay, we're at a site that played a part in a famous British disaster story.

♪♪ In 1845, explorer Captain John Franklin departed England with two ships, HMS Erebus and HMS Terror.

For centuries, European explorers had been looking for a navigable passage as a trade route to Asia, but they were always blocked by the ice.

Franklin's mission was to make it to the last unnavigated, icebound sections of the infamous Northwest Passage through the Canadian Arctic.

When Franklin reached these waters here in Disko Bay, he met one whaling ship.

The whalers reported him and his men were in very good spirits.

He then sailed north off the map and into the unknown.

But shortly after, the expedition met with disaster when both ships and all 129 men became trapped in ice.

Stories of hypothermia, starvation, and even cannibalism are now the stuff of legend, and, eventually, every single one of Franklin's expedition perished in this hostile environment.

♪♪ ♪♪ ♪♪ Following in the footsteps of Franklin's doomed expedition is daunting.

There are dangers everywhere, and ice mist can roll in off the land, making life at sea treacherous.

♪♪ Ironically, warming sea temperatures mean this passage will one day become a regular sea lane.

♪♪ The icebergs loom out of the mist like ghosts.

They can be just 50 meters away and almost invisible in this white horizon.

And not only that, there could be submerged icebergs, called "growlers," that we could easily run into, and considering the Kisaq's got a wooden hull, the crew have to take this really seriously.

At all times, there are people looking out for the ice.

♪♪ It's easy to see how the tragedy of the Titanic happened when that famous ship struck a massive iceberg.

If the conditions then were anything like what they are today, the visibility and just the general haze and the mist prevents you from seeing the icebergs until it's too late.

♪♪ ♪♪ For much of the wildlife here, icebergs provide a welcome resting place.

The captain has decided it's too dangerous to continue in these misty conditions.

So, like these walruses, we're going to take a break and moor up.

♪♪ This snowy owl is using the cover of mist to search for young bird chicks.

♪♪ ♪♪ This is one of Greenland's many small islands, and as visibility improves, we can see that it was once inhabited.

♪♪ This was settled over 1,000 years ago.

♪♪ ♪♪ There's evidence of simple dwellings and even crop growth.

People have long since left this island, and now it's home to wildlife like these red-necked phalarope and eider ducks.

♪♪ But we're here on this island, one of dozens dotted around Greenland, for one very special resident.

[ Birds calling ] ♪♪ This is Green Island, home to the largest Arctic tern breeding site in the world.

This tiny bird undertakes the greatest migration of all animals, traveling from here to overwinter down in the Weddell Sea off Antarctica, some 20,000 kilometers away.

[ Calling continues ] ♪♪ This journey means that this bird sees two summers a year and more daylight than any other creature on the planet.

And when it stops off here, the Arctic tundra provides the perfect home for its nests, with excellent camouflage for the chicks.

♪♪ Arctic terns can live for over 30 years, and during that time, they'll fly over 2.5 million kilometers.

That's the equivalent of flying to the moon and back three times.

Arctic terns will also defend their nests by dive-bombing any intruder.

[ Birds calling ] ♪♪ It's time to move on.

♪♪ Back on the Kisaq, we're beginning to think about the next leg of our journey north.

We need to stop for some vital supplies, so we're heading for Upernavik, one of the last supply towns on our journey before moving into the High Arctic.

♪♪ ♪♪ Upernavik is part of an archipelago near Baffin Bay.

♪♪ It's one of the earliest settled areas of Greenland, when the first migrants arrived from North America around 2,000 B.C.

The town itself was formally founded in the 18th century, when the Danes first colonized Greenland.

For large parts of the year, it can only be reached by air.

During the summer, a ship like this will arrive twice a month to drop off supplies for the town, but in winter, when the sea freezes over, they get absolutely no supply ships at all, and they have to hold out on their own until the sun reappears.

Right.

Now the goods are in, it's time to head to a local store.

And shotguns and rifles are a strange thing to see first.

In a way, it's a miracle to find such bounty in this remote town.

We're not going to find anything like this when we head north.

♪♪ Upernavik, like all towns and settlements, sits on the edge of Greenland's vast ice sheet, and whilst people don't live on the ice, it does provide them with food, especially in winter.

Because it's summer, there's no snow down here in the lowlands, but up in the hills, there's still ice and glaciers, and there are active sled-dog teams.

So we're going to climb up and see if we can go out with one of the dog teams.

♪♪ In winter, with the oceans around them frozen over, the Inuit depend heavily on dogs and sleds, not just for transport but for hunting.

♪♪ There have been dogs on Greenland for over 4,000 years, and with their thick fur, they are superbly adapted to life in these cold temperatures.

♪♪ If we can make it up to the top, Ikan has offered to take us out on the ice.

[ Dogs barking ] The Inuit have used sled-dog teams for thousands of years to hunt seal, caribou, and even polar bears on the ice.

And these clothes aren't just for show.

Even in summer, it's very cold on the ice, and these sealskin furs are perfect for keeping warm.

♪♪ ♪♪ -[Shouting in native language] -For the Inuit, these are not pets, they're work dogs, and the leader must be kept in check.

He has to keep them together in one pack to pull the sled forward.

These sleds enable the Inuit to travel vast distances over the snow and ice, and subsistence hunting is important here.

As well as using the meat for food, no part of the animal is wasted.

This sled is lined with reindeer fur, and the clothes are made out of sealskin and polar bear.

♪♪ -[ Calling ] -The dog-sled drivers make these different whistles and sounds, and the dogs immediately understand the commands.

It shows how incredibly close the relationship is.

It's hard to imagine how the Inuit can survive in this incredibly harsh landscape without them.

♪♪ Our boat's called the Kisaq, which means "anchor" in Greenland's Inuit language.

We're hoping that's a good omen as we set sail on the next leg of our journey north, because, as we head up along the coast, the weather's taking a turn for the worse.

We're getting into the High Arctic, the wild Greenland.

♪♪ Our plan is to head north to the more remote parts of Greenland and to meet the people who live in one of the most isolated places on the planet.

Our aim is to reach Siorapaluk, which is the most northern natural settlement on Earth.

[ Birds calling ] ♪♪ ♪♪ By morning, the storm has passed and the calmer waters are providing food for this huge colony of guillemots and kittiwakes.

Over the years, seabirds have been overhunted, and their numbers have been declining.

These days it's becoming rare to see colonies like this.

♪♪ There are guns on the Kisaq, and Carsten explains why we need them.

-We're now moving north, so we're moving into polar bear territory, so it's important, as a precaution, to -- to carry a rifle at all times now every time we go ashore.

The chances of actually meeting a polar bear at this time of the year -- they're rather small, but -- but we need to do it from now on.

-Guns are only carried to scare the polar bears, and Carsten needs to test them regularly to check that they're in good working order, just in case.

[ Gunshot ] ♪♪ ♪♪ We want to leave the safety of the Kisaq and go ashore to explore.

♪♪ This is an area where polar bears are regularly sighted, so Carsten insists on going ahead to check the coast is clear.

♪♪ These tracks have been made by an adult polar bear.

Thankfully, they're are a few days old, and Carsten is happy that it's moved on.

♪♪ We get the all-clear to leave the boat.

As we get further north, the landscape is becoming increasingly desolate, but there are some surprises.

We're here to experience one of Greenland's natural wonders -- an extraordinary rich, green landscape amongst the barren terrain of the High Arctic, a place with a unique ecosystem.

♪♪ ♪♪ This valley is like a little oasis, a miniature world contained within these slopes, and the sheer abundance of life here is absolutely staggering.

♪♪ ♪♪ The reason that all this bounty exists is down to one tiny bird, the little auk -- actually, not just one but millions of them!

♪♪ ♪♪ Every summer, 60 million little auks travel from Newfoundland to their breeding grounds here in northwest Greenland, and they arrive just as the phytoplankton in the ocean is boosted by the warming temperatures.

These tiny birds drop literally tons of guano here every single day, and it's this release of nutrients that flows down and sustains the ecosystem in the valley slopes below.

♪♪ The auk guano transforms the landscape.

It creates an oasis of grass and flowers that, in turn, is food for many larger animals.

But the fate of this oasis is balanced on a knife edge.

As the climate warms, the phytoplankton are starting to appear at the wrong time for the auks' migration, and all of this could soon be lost.

Oh, my goodness.

-Oh, that's cool!

-Ohh.

When we get back to the Kisaq... -Aah!

-[ Laughs ] -...we find the crew engaged in some rather eccentric behavior.

-I'm alive!

Ohh!

-Even in summer, these waters are icy cold.

This will certainly toughen everyone up for the journey ahead.

-You can't go back so soon!

You only just got in!

-That was like an hour!

Ohh!

[ Laughter ] ♪♪ ♪♪ -As we push further north along the coast, the waters are thankfully calm, giving us a chance to enjoy some of these extraordinary floating mountains of ice.

♪♪ These icebergs are formed when they break away from glaciers that push out to the coast around the edges of Greenland's massive ice sheet.

They can be sculpted into extraordinary shapes by the elements, and none more so than this one, which has an enormous archway.

♪♪ It's time to move on.

But as we get to a safe distance away, one of the crew alerts us to some movement in the ice.

[ Rumbling ] That was close!

When massive bergs break apart, they can be lethal.

♪♪ Events like this stir up the nutrient-rich waters... ♪♪ ...creating an opportunity for whales like these to feed on the plankton here.

♪♪ The ocean doesn't just feed the wildlife, it provides a lifeline for the Inuit, who live in a handful of small fishing villages along the coast of northwest Greenland.

♪♪ ♪♪ ♪♪ We want to find out more about the fishermen here and how they survive, especially in the harsh winters in this extreme part of the world.

But people here don't just fish, they hunt whales and dolphins, taking just what they need to sustain their communities.

And although they now have modern equipment and boats, some of the hunting and fishing techniques have not changed for centuries.

This man has been hunting narwhal, a much prized member of the whale family.

♪♪ This traditional method of using a lightweight kayak and a harpoon is an ancient one.

♪♪ ♪♪ When a catch is landed, it's often butchered immediately.

The dogs are sometimes the first to get a meal.

[ Dogs whining ] ♪♪ We've been invited to come ashore.

♪♪ Meat and blubber from a narwhal provides an important source of calories this far north, and the Inuit sometimes eat their meat raw because of a traditional belief that it keeps them warmer and makes them stronger.

Meat is often hung up in the sun to dry and preserve it.

This is very much part of the local tradition and customs and, in fact, how local people here eat.

♪♪ But this traditional village way of life is under threat.

♪♪ As the ice melts, narwhals are losing their habitat.

♪♪ That melting ice brings ships and their noise pollution, which, in turn, disrupts the narwhals' ability to navigate.

Now populations have plummeted to critical levels, and some people want to ban hunting altogether.

This might be the last we'll see of this ancient culture.

♪♪ We have been invited to spend time with an Inuit family in Savissivik to experience firsthand their way of life and to see some of their ancient traditions.

♪♪ Savissivik is one of the northernmost human settlements in the world.

It was first populated in 2000 B.C.

by nomadic polar Inuits, and the people speak the local Inuktun language.

This place feels like a real frontier town.

It's raw and rugged.

This is the essence of the extreme north of Greenland.

[ Birds calling ] ♪♪ ♪♪ ♪♪ ♪♪ ♪♪ For Gideon and his family, the little auk we met earlier provides a valuable food source.

♪♪ This is true subsistence hunting.

They only take what the community needs.

And this tradition of catching them in nets has been used by generations of Inuit.

♪♪ As we explore, it soon becomes clear that Gideon and his family hunt polar bear, one of the most ferocious predators in the world.

♪♪ ♪♪ For the people here, the polar bear's fur is key to their traditional way of life.

We have been invited to try on the Inuit clothing that they wear when hunting on the ice.

The clothes, like these sealskin boots, are made here in the village, and the detail in the stitching is remarkable.

The gloves are also made of sealskin and polar bear.

[ Indistinct conversations ] These trousers are lined with sealskin with polar bear fur.

Temperatures can drop to below -40 degrees Celsius here, and you just can't get a warmer, more insulative material than this to protect against the harsh winter climate.

[ Conversations continue ] It's important to familiarize the dogs to humans wearing the traditional clothes so that they can tell the difference when they're hunting polar bears.

[ Conversations continue ] Gideon's family have been preparing the little auk they caught earlier.

To eat them, you have to peel the skin, a bit like a banana.

It's dark meat -- tastes similar to chicken.

After dinner, there's time to catch up with Gideon and ask him about the dangers of hunting such a powerful predator and just how he does it.

The dogs work as a pack to trap the bears and provide the hunters with protection.

He used to catch bears in his area, but climate change has made life much harder.

Gideon is concerned for his grandchildren's future.

♪♪ It's devastating to hear how the loss of sea ice is affecting polar bear habitats, and when the polar bears go, so will this traditional way of life.

♪♪ Hunting might seem brutal, but it's been sustainable for thousands of years.

Unlike most Western farming, nothing is wasted.

If we're to save the planet, perhaps we, too, in the rest of the world, should adopt a more sustainable way of life.

♪♪ We're heading north, almost at our journey's end.

As we travel, the mist descends over the waters once again, making life amongst the icebergs treacherous.

Then, on the distant shoreline, through the mist, we spot something.

♪♪ ♪♪ ♪♪ Fully grown male polar bears can weigh up to 3/4 of a ton, and this one has certainly attracted the attention of the local residents.

Polar bears are great swimmers.

Sadly, the ever retreating ice means they often now have to swim vast distances in search of prey.

What a joy to see this magnificent creature in the wild.

This is the largest land predator on Earth, and they have been known to track humans, so it's time to move on.

After weeks on the water, we've nearly made it to our final destination.

♪♪ Through the mist, we can just about make out a few homes.

This is Siorapaluk, the northernmost natural human settlement on Earth.

♪♪ ♪♪ It's been awe-inspiring and hugely humbling to learn about this remote land and its people, all the more so because of the critical threat to Greenland's ice sheet and all the life that depends upon it.

So, we've made it.

Somewhere in the mist behind this town, there's an invisible line that marks the end of the realm of man.

It's amazing to think that no human being lives further north of here on our planet.

This is the end of our range as a species.

What a testimony to the survival skills of the few hardy Inuit who live here.

♪♪ But before we leave Greenland, there's one more adventure to have.

♪♪ We want to find out what lies beyond the realm of man.

♪♪ ♪♪ We need to get above the cloud line before we can see anything.

♪♪ This land has an otherworldly quality.

It's like walking on the face of some distant planet.

♪♪ ♪♪ Almost nothing can live here.

Even in summer, conditions are just too difficult for life to thrive.

♪♪ The landscape is dry, barren, and frost-shattered.

There's little soil and virtually no plants.

We haven't seen any birds or animals, and it's easy to see why we just simply can't survive here.

♪♪ ♪♪ ♪♪ We head back to the coastline, where there is life and where, for millennia, people have carved out an existence in this Arctic landscape.

It's now up to all of us to act on climate change to save their way of life.

♪♪ ♪♪ ♪♪