(bright music) - [Narrator 1] Ice, it is simply frozen water, but it can be as small as an ice cube or as big as an iceberg.

Ice can be as mobile as a glacier, as feather light as falling snow, or heavy enough to carve up fjords.

Ice is the hallmark of our polar regions, creating unique environments only the hardiest creatures can endure.

And when ice turns into an Ice Age, our planet's destiny changes forever.

Melting, freezing, then melting again, ice is Mother Nature's shape-shifter, and definitely the coolest icon-maker.

(bright music) One of the most majestic and little-known ice icons on our planet, is this.

Garibaldi Glacier.

Situated in the Beagle Channel of Southern Chile, this frozen icon is considered the world's most beautiful glacier.

(bright music) Visually it appears to link sky to sea, with a towering face several stories high.

(bright music) Glaciers like Garibaldi form over many centuries, when snowfall accumulates faster than it dissipates.

Snow compacts into ice, which builds up height and length.

Although not perceptible, this huge body of ice is constantly moving under its own weight, and is heavy enough to have ploughed out the fjord in which it's cradled.

And gives Garibaldi its iconic colours.

(bright music) Brown lines called "medial moraines" show where rock has been collected by ice flow, and pushed into lines, as smaller glaciers meet and fuse.

Only found on top of or inside glaciers, if Garibaldi should ever retreat, these medial moraines would remain as a long ridge of earth.

(bright music) But one of Garibaldi's most eye-catching features, is the colour of its ice.

And the blue hue is due to compression.

In dense glacial ice like this, air bubbles have been squeezed out.

It's the air in ice that gives it the classic white colour.

(bright music) But compressed ice, like deep water, absorbs the red colour spectrum and reflects the blue.

The more compressed the ice, the bluer it looks.

But no need to feel blue, this glacier has plenty of company.

(bright music) Many other forms of ice are adrift in the Garibaldi fjord.

When water freezes it increases in volume but decreases in density, enabling ice to float.

(bright music) Paradoxically, the Garibaldi Glacier is the frozen jewel of Chile's Tierra del Fuego, or "Land of Fire."

The archipelago was named after explorer Ferdinand Magellan, the first European to discover the waterways in 1520.

(bright music) This is the southernmost part of the mighty Andes' range, where fjords and channels snake towards Cape Horn, the Drake, and Antarctica beyond.

These waterways are important navigable routes for ships accessing Chilean ports, both for commerce and ecotourism.

(bright music) What you see beyond the decks is a landscape literally frozen in time.

Tens of thousands of years ago, southern Chile was totally covered by a vast ice sheet.

When the glacial period ended, the ice sheet melted away and what remains are the Patagonian Ice fields, three vast areas which include Garibaldi Glacier.

(bright music) Today, 90% of Chile's ice fields have shrunk due to global warming.

But, although a shadow of its former self, Garibaldi still holds the title of the second largest extra polar ice field on the planet.

(bright music) To find the largest ice field on our planet, one must travel south from Garibaldi Glacier, to the extraordinary landscape that is Antarctica.

Occupying the planet's south pole, Antarctica is the fabled "White Continent," with a land mass almost twice as large as Australia.

Or roughly the combined size of Mexico and the United States.

(bright music) Home to 90% of the planet's ice, Antarctica is the largest unbroken piece of ice on earth.

At its thickest, it's 4,776 metres deep.

It's estimated that if the weight of Antarctica's ice were removed, the underlying rock would rise on average by 1,000 metres.

(bright music) Antarctica's size is not fixed.

(crushing of ice) The sea ice for example, increases dramatically from 3 million square kilometres in summer to around 19 million square kilometres in winter.

(bright music) The best time to visit Antarctica is between November and March, summertime in the south pole, when temperatures can reach a bearable zero degrees Celsius and there's almost 24 hours of daylight.

(bright music) One of the best places to access Antarctica is the Antarctic Peninsula.

(bright music) This 1,300-kilometer-long finger of earth, is located on the northwest corner of the White Continent, two days hard sailing across the mighty Southern Ocean.

(bright music) The Peninsula consists of both continental landmass and many islands.

Most of these islands are ice-covered, connected to the land by pack ice, the glue that welds the Peninsula together.

(bright music) But ironically, it was fire that first created this region.

(bright music) About 180 million years ago, a vast geological supercontinent called Gondwanaland, broke up and gave birth to several smaller continents such as Africa, South America, Australia and the most southern continent, Antarctica.

Mountains buckled upwards along the peninsula, and volcanoes created most of the islands.

Hot springs still bubble in many bays.

Gaps in the ice reveal the reddish-brown earth of lava, ash and granite, which is visual proof of the Peninsula's volcanic history.

(bright music) Antarctica is a place of contrasts.

Although covered in ice, it's classified as one of the world's driest deserts with on average, only 150 millimetres of rain falling each year, as snow.

It's also the windiest and coldest place on earth.

With temperatures dropping in some places to minus 60 degrees Celsius.

(strong wind blowing) So its creatures have evolved to live on ice, to the point that some now depend upon it for their survival.

(bright music) Humpback whales migrate here every summer to feast on krill, a small crustacea resembling shrimp, which in turn is sustained by microbes and algae residing in ice.

(bright music) All six Antarctic seal species rely on ice for habitat or diet.

(seals roaring) Somewhere between half a million and a million seals live here.

(seals roaring) Crabeater seals are particularly ice-loving.

They prefer to haul out on floating pack-ice, and travel with it throughout the seasons.

(rumbling of ice) Watching them are orca.

(bright music) Antarctic pods specialise in seal hunting, and work cooperatively to wash seals off ice.

Orcas are indiscriminate carnivores, eating everything from penguins to squid to other whales and of course, seals.

(water splashing) (bright music) But the best ice mascot, is the penguin.

(bright music) This bird's evolution is completely tied to the deep freeze.

Their bodies are insulated with blubber.

Their feathers are waterproof.

And when they fly, it's strictly underwater.

(bright music) Penguins' feet are also ice-adapted.

Webbing between their toes shows they've long farewelled tree roosting, in favour of the aquatic, and their claws are designed like crampons, to grip slippery surfaces.

(bright music) It's difficult to be certain but it's estimated there are 20 million breeding pairs of penguins in Antarctica.

Five species of penguins are found in Antarctic waters, and three, the Adelie, Gentoo, and Chinstrap, all breed on the Peninsula.

Each year, they return to the nesting sites where they hatch, and reunite with lifelong partners through song.

(penguins singing) Although the breeding colonies are surrounded by ice, the penguins prefer ice-free nest sites, seeking out exposed areas during the summer breeding period.

(bright music) To make the nests even higher and drier, they build them up with pebbles.

(bright music) And if they haven't got enough, they'll steal from a neighbour.

(bright music) Penguin breeding cycles coincide with summer, and numbers are dependent on food availability.

Once the chicks have hatched, the demand for food is endless.

They're fattened on fish, squid and crustacea caught beneath the ice.

(penguins honking) Since they evolved from birds some 50 million years ago, life for Antarctic penguins has remained stable and in harmony with their environment.

(bright music) Penguins arrive and depart from their breeding colonies as season and ice cover dictate.

For aeons, the food and habitat offered by ice has enabled penguin colonies to boom.

Now global warming and loss of ice, directly correlates to the decline in penguin populations.

It's a matter of holding on tight to a melting world.

(bright music) Antarctica is a breeding ground for more than just penguins.

One of the most beautiful and certainly the biggest of Antarctica's offspring are these, icebergs.

Icebergs are large chunks of ice that break free of the mainland and float on the ocean.

And icebergs come in all shapes and sizes.

In 2021, an iceberg 170 kilometres long and 25 kilometres wide, about the same size as the state of Rhode Island in the US, broke off from western Antarctica.

It's the biggest iceberg ever recorded.

(bright music) Other icebergs are more modest in scale, but they've been sculpted by wind and water into some of the most hypnotically alluring shapes in the natural world.

(bright music) These icebergs are one of the main drawcards for humans who venture to the "White Continent."

The desire to see Antarctica ignited tourism in the 1950s.

It's a multi-million-dollar industry, with tens of thousands of visitors coming each year.

Many fear the impact of such intense human presence.

But others argue that to fall in love with this icon, and be inspired to protect it, you need to see, smell and taste it.

And return home with ice in your veins.

(bright music) (feet thumping) Neither thick ice nor frostbitten toes have deterred humanity's quest to explore every frozen corner.

And journeying by foot, is still the preferred way to discover one of the southern hemisphere's most revered ice icons, Cradle Mountain.

(bright music) Set in the pristine north western wilderness area of Tasmania, an island off the southern coast of Australia, Cradle Mountain is on the bucket-list of any serious hiker.

(bright music) It rises 1,545 metres above sea level, and is located on a high windswept plateau.

(bright music) Walking trails rather than roads traverse it.

There is no ring road around the mountain, and definitely no lift to the top.

Step by step is the only way to get closer.

And every step is a step back in time.

(bright music) All the way back to Antarctica.

(bright music) Cradle Mountain is a reminder of the supercontinent Gondwana, when Australia and Antarctica were fused.

But when they began to separate 80 million years ago, magma was released and Cradle Mountain was born.

It's composed of a unique lava basalt also found in Antarctica.

(bright music) The mountain gets its name from the distinctive narrow ridge at its peak which resembles a cradle.

(bright music) The landscape around Cradle Mountain, is some of the most dramatic and varied on Tasmania, and the handiwork of ice is everywhere.

Over two million years, three separate eras of glaciation shaped Cradle Mountain and hollowed out a series of lakes in its surrounding area.

(bright music) The most famous is Lake St Clair, the deepest freshwater lake in Australia, and whose local Indigenous name, Leeawuleena, means "sleeping water."

(bright music) The lake forms the southern end of the Cradle Mountain-Lake St Clair National Park, notable for its Jurassic peaks and glaciated "moraines."

(bright music) Even in summer when snow cover is minimal, these ridges and mounds remind of the power of ice.

And what it can do to a landscape given enough time.

(bright music) Cradle Mountain also earns its ice-icon status, because of its climate.

This climate is classified as subpolar oceanic and experiences high rainfall and snow year-round.

In the lower slopes of the Mountain, temperatures might only fall as low as six degrees Celsius.

Temperate compared to Antarctica, but critical in that it allows flora to flourish.

(bright music) The alpine vegetation is diverse and ice-resistant, and includes ancient plants of Gondwanan origins, all of which have adapted to the conditions on Cradle Mountain.

Forests of peppermint and swamp gums, pines and beech trees stand resolute in the sleet.

Frost-resistant mosses, button grasses and heath carpet the moorlands, bejewelled by frozen droplets.

(bright music) As a protected National Park, Cradle Mountain has become an ark for hundreds of animal species.

(bright music) And iconic Australian animals, normally associated with warmer climes, have adapted to live here happily, in truly icy conditions.

(bright music) It's difficult to imagine today, but so many of our planet's countries and continents can trace their ancestry back to the icy continent of Antarctica.

And one of Antarctica's most spectacular relations is also one of its closest.

(bright music) When Gondwanaland split apart, a huge mass of continental crust called Zealandia moved northward beneath the Pacific Ocean.

But two small spots broke the surface.

Today they're called the north and south islands of New Zealand.

(bright music) Two thirds of the South Island are snow-capped mountains.

And the star of these is Mount Cook or Aoraki.

(bright music) Mri legend explains this mountain as the frozen corpse of an ancestral being.

Aoraki was the son of Rakinui, the Sky Father, and perished when his canoe sunk.

(bright music) Both were turned to stone by the icy winds, and the canoe became the South Island and Aoraki and his brothers became the peaks of the Southern Alps.

(car engine roaring) (bright music) The Alps extend approximately 650 kilometres along the western side of the South Island.

With 24 of its peaks measuring over 3,000 metres.

But towering above them all, is Aoraki.

(bright music) Aoraki is the highest mountain in New Zealand, rising over 3,700 metres.

(bright music) The mountain lies in the centre of the volatile Alpine Fault, a 650 kilometre long active faultline which runs through the Southern Alps.

(bright music) It was formed by tectonic uplift, which continues to this day, so that every year Aoraki grows a few millimetres taller.

(bright music) But, however tall Aoraki grows, no-one will ever set foot on its peak.

For Indigenous Mri, Aoraki's summit is sacred, and to step on it would violate its status.

(bright music) This is hardcore mountaineering country, and the training ground for Sir Edmund Hilary before his conquest of Everest in the 1950s.

(bright music) - [Narrator 2] The majestic Tasman Glacier in the southern alps of New Zealand, is an ideal training ground for the forthcoming New Zealand expedition to the Antarctic.

Sir Edmund Hilary will be leading the expedition, which forms one of the activities during the international geophysical year.

(bright music) - [Narrator 1] It continues to inspire fitness to this day.

(bright music) Aoraki is the jewel of the Aoraki-Mount Cook National Park, which was established in 1953 and is a UNESCO World Heritage Site.

(bright music) This park is home to New Zealand's highest peaks, longest glaciers, and permanent snow fields.

(bright music) But it's in the water where ice really works its magic.

(glaciers roaring) Glaciers pulverise rock and fill meltwater streams with a fine silt called "glacial flour."

When this enters a lake, the silt doesn't sink but remains suspended in the water column.

(bright music) Both water and particles absorb colours in the red spectrum, and reflect back blues and greens.

The result is a turquoise colour, glowing neon in the sun.

(bright music) These gems can be seen from outer space, as captured by NASA earth observatories.

NASA identifies four lakes on the South Island which stand-out due to their turquoise colour.

Lake Tekapo, Lake Pukaki, Lake Ohau and Lake Benmore.

(bright music) From the stars, it's also possible to see the frozen form of Aoraki in all its glory.

And even watch it avalanche.

(bright music) Back down on earth, the most iconic glacial flour lake is found on the other side of the planet, in Alberta, Canada.

(bright music) This is Lake Louise.

(bright music) Named after the fourth daughter of Britain's Queen Victoria, Lake Louise, like New Zealand's turquoise lakes, is fed by glacial meltwater and owes its colour to suspended silt.

(bright music) Located in Banff National Park in Alberta, it is one of Canada's most photographed wonders.

And in the warmer months, over 15,000 people per day pay a visit.

(bright music) Inevitably, summer is followed by winter and temperatures at Lake Louise can drop as low as minus 23 degrees Celsius.

Unsurprisingly, visitor numbers thin during the winter, but the ice thickens.

In fact, every year the lake freezes over and doesn't thaw out until well into spring.

(bright music) Assisting ice in this lake-take-over, is Lake Louise's high elevation of over 1,600 metres.

Even in midsummer, the water temperature rarely gets above 5 degrees Celsius.

(bright music) The route taken by visitors to the lake, is as iconic as the lake itself.

(car engine roaring) This is the Ice field Parkway.

Linking Lake Louise to the south, with Jasper National Park to the north, this highway is considered one of the most picturesque on the planet.

And for 230 kilometres, the Ice field Parkway is true to its name.

The highway runs parallel to the Continental Divide, traverses the Canadian Rockies, and cuts through jaw-dropping scenery of mountain peaks, sweeping valleys and ice fields.

(bright music) Prior to the Parkway, access to the area was limited to Indigenous tribes and early European fur trappers and hunters.

But in 1931, the Canadian government decided to build a single-track road as an economic stimulus project during the Depression.

Today, 1.2 million people make an annual pilgrimage along this breathtaking road, to take in the area's extraordinary landscapes, which is complete with year-round ice caps.

(bright music) One thing to keep a look out for is wildlife.

This area is teeming with native fauna.

Over 50 mammal species live in this stretch of The Canadian Rockies, including two species of bear, the black and the grizzly.

(bright music) One of the most common sightings from the Parkway, are North American Elk.

These large deer are jay-walkers.

(bright music) And thankfully pretty good at it.

(bright music) Ice cover, and associated food access, dictates the life-cycle of the elk.

(bright music) Autumn compels the elk to forage constantly, gaining weight to survive winter.

Elk have the ability to store excess food in their stomachs, which they regurgitate when a sustaining snack is required.

(bright music) When favourite grasses become buried in snow, they change diet to twigs and leaves.

As winter descends, they take refuge in valleys.

In summers warmth, they range the high country.

In response to ice, they shed or regrow fur coats, and slow down or speed up their metabolism.

(bright music) And melting snow is an elk's aphrodisiac.

(horns clunking) It's the springtime cue to grow antlers, and go to battle.

(horns clunking) (bright music) Before it reaches its end, the Ice field Parkway has one last surprise.

Straddling the border between British Columbia and Alberta is the Columbia Ice field, the largest ice field in the Canadian Rockies.

(bright music) This Ice field was formed during a period of extreme glaciation, some 240,000 years ago.

It covers 230 square kilometres and reaches a depth of 365 metres, making it one of the largest non-polar ice fields in the world.

(bright music) Within the Columbia Ice field there are 25 glaciers and whilst the ice field has been slowly shrinking due to a warming climate, the number of tourists drawn here, increases steadily.

(bright music) The majority come to visit one of the most majestic natural icons in the Rockies, the Athabasca Glacier.

(bright music) The Athabasca is a huge tongue of ice that spills over three enormous bedrock steps, as it makes its way down between Mounts Andromeda, Athabasca, Kitchener and K2.

(bright music) Part of the glacier's attraction is, undoubtedly, its accessibility.

Tourists can drive just over two kilometres from the Parkway, and from there take tracked vehicles, called Ice Explorers, onto the glacier itself.

In places, the ice is 300 metres thick.

That's equivalent to the height of the Eiffel Tower.

So there's no chance of the glacier cracking underfoot.

(crowd chattering) Athabasca is constantly fed by snow, with up to 7 metres falling per year.

At the top end of the glacier, fresh snow shines white.

Over time, and seasons, the snow melts, freezes and compacts as it travels downwards.

(bright music) Ravines and crevasses open and close, making the higher terrain treacherous.

(bright music) By the time the glacier peters out, 6 kilometres from where it began, the ice is so compressed it's blue in colour.

(bright music) Summer warmth and climate change reverts some of this ancient ice to water.

(bright music) The water from Athabasca and the wider Columbia Ice field flows via river systems in every direction, eventually draining into the Arctic Ocean to the north, the Pacific Ocean to the west and the Atlantic Ocean to the east.

In this simple and magical way, ice, transformed into water, connects the highest peaks of our planet to its darkest depths.

(bright music) More than 29 million cubic kilometres of ice covers the planet's surface.

(aeroplane engine roaring) This ice is distributed between the Antarctic ice sheet which covers 8.3% of the earth's land surface, whilst the Greenland ice sheet covers approximately 1.2%, with glaciers and ice caps making up only 0.5% of the total ice coverage.

(bright music) Unfortunately, the volume of ice in these regions is decreasing rapidly.

Between 2012 and 2106, the Greenland ice sheet alone lost 15 gigatonnes of ice per year.

That's 15 billion tonnes of ice that's been lost, flowing into the sea and contributing to global sea level rises.

The rest of our frozen freshwater, is locked up in alpine areas and glaciers worldwide.

This leaves just 1% of the earth's water available to us for our daily needs.

(bright music) In many ways, a waterfall is water wastage.

(bright music) But that's the last thing on anyone's mind when visiting one of the world's waterfall capitals.

(bright music) Norway's fjordland.

(waterfall roaring) According to the world waterfall database, Norway boasts 10 of the world's 30 tallest waterfalls.

(bright music) The tallest, Mongafessen, is 773 metres high, which is just over double the size of the Empire State Building.

(bright music) But behind every great waterfall, is great ice.

Ice determines the ebb and flow of all these falls, and it's ice, not water, that makes the Norwegian Fjords iconic.

(bright music) During the last Ice Age, approximately 20,000 years ago, a huge part of Northern Europe was covered in a thick ice sheet, up to 2 kilometres deep.

Over time, giant glaciers scoured and segregated the bedrock, carving deep U-shaped valleys which we now call fjords.

(bright music) A true fjord is always longer than it is wide, and is normally deepest farther inland, where the glacial force was strongest.

(bright music) Fjords are typically shallow at the entrance, where gravel and sand was deposited by the glacier as it lost strength and momentum.

(bright music) All this, equals easy cruising for even the biggest cruise ships.

There really is no other way to access nor appreciate this ice-carved countryside, than via the water.

And to sail here, is to imbibe a Viking's seafaring spirit.

(bright music) The word 'fjord' derives from the Viking or Norse word "fjoror" which translates as "where one fares through" or "where you travel across."

(bright music) Now "fjord" is one of the few Norwegian words known internationally, and it draws an international crowd.

(bright music) The tiny village of Flam, huddled at the end of Aurlandsjorden, has less than 400 permanent inhabitants.

But every year over 450,000 tourists pay a visit.

(bright music) More than 1,000 fjords are found in Norway, and UNESCO has included this entire fjordland on its World Heritage List.

(bright music) After Greenland's Scoresby Sound, Norway has the next two longest fjords in the world.

The 203-kilometer long Sognefjord, and the 179-kilometer long Hardanger Fjord.

All of which, were forged by ice.

(bright music) The Norwegian fjordland has been shaped, over millennia by ice.

But there are places on earth that have been shaped as much by the absence of ice, as its presence.

This is the Mendenhall Glacier which sits in the Juneau Ice Field, in southeast Alaska.

(bright music) Thirty-seven glaciers make up the Juneau Ice field, which covers an area of 3,800 square kilometres, a third larger in area than the whole state of Rhode Island.

(bright music) The ice field also stretches nearly 185 kilometres from north to south, and just over 70 kilometres from east to west.

(bright music) Mendenhall Glacier, which is 22 kilometres in length, is the only glacier in the Juneau Ice field accessible by road, which has done much to put this icon on the map.

But, as imposing as Mendenhall is, it's retreating fast due to climate change, and over the past century alone it has withdrawn by approximately 3 kilometres.

Scientists term this as "negative glacier mass balance," whereby the glacier is reducing faster than snowfall can rebuild it.

(bright music) There is, though, an upside of sorts to glacial retreat.

In its wake, Mendenhall glacier leaves a lake, 2.4 kilometres long, 1.6 wide and 65 metres deep at its centre.

The Mendenhall Lake first appeared in 1929, when the glacier retreated enough to expose a deeply scoured valley.

(bright music) Meltwater from the glacier filled the valley, and Mendenhall Lake came into existence, which now covers a few hundred acres and hosts a variety of cold-water fish.

(bright music) Upwards of half a million visitors make the journey to Mendenhall Lake during the summer months.

And from the visitors' centre, the hardiest can go on to explore the glacier, by canoeing across the lake or taking a 12-kilometer round trip on foot via a hiking trail.

(bright music) As the Mendenhall Glacier retreats, it uncovers bare ground which is a fertile bed for new life.

Wind carries seeds and other plant spores which find a home to grow and this new growth eventually adds more organic matter to the soil.

The result is a transformed landscape.

(bright music) Instead of thick ice, thick forest now dominates the area.

Mendenhall Lake is part of the 17 million-acre Tongass National Forest, and is rich in wildlife.

(bright music) This part of southeast Alaska is wolf country.

Brown and black bears overwinter here in dens, and emerge in spring to feast and spar in the shallows.

(bears growling) Both the lake, and the life it supports, is a positive from the negative of a vanishing glacier.

But ice giveth, and ice taketh away.

(bright music) Mendenhall Glacier sits at the northern end of Gastineau Channel.

This 25-kilometer strip of water, separates mainland Alaska from Douglas Island, and presents a peaceful panorama of whites and greens.

But beneath the emerald surface, there's havoc.

The melting of Mendenhall is filling the channel with sediment and silt.

(bright music) And without the weight of ice, the earth rebounds slowly, making the channel more shallow, so that at each low tide, water turns into mud flats.

This is having a huge economic impact in the area.

With each passing year, the channel becomes less navigable, which restricts access to the town of Juneau, which depends on cruise ships for much of its income.

Losing ice has come at a cost.

(bright music) From the tiniest snowflakes, to the largest ice sheets, ice has long made its presence felt on earth.

From the north pole to the south pole.

From mountain caps to glacial lakes, ice has proven itself the ultimate sculptor.

Out of its deep freeze, unique life emerges.

(bright music) Under its weight, majestic landscapes are born.

Melting and refreezing, ice reminds us of the power of impermanence.

(bright music) Whilst leaving behind enduring icons, to defy the imagination.

(bright music)