(Majestic music)
NARRATOR: In a realm of snow and ice...
(Ice crackling)
..water transforms into nature's most powerful sculptor.
From fragile snowflakes...
to towering glaciers...
..it shapes landscapes...
(Low bellow)
..and lives.
Driving epic journeys...
..extraordinary adaptations...
..and crowning rulers.
This is the magic... of frozen water.
(Waves crashing)
Take a dive into our planet's mesmerising world of water.
(Epic music)
From the monumental open ocean,
to the rugged coasts that serve as the dividing line
between two worlds.
From the changing rivers that carve through continents...
..to mysterious lakes and swamps.
Immerse yourself in the magic that unfolds...
..as we reveal...
The Secrets of Our Enchanted Waters.
(Gentle music)
Water shapes life in the most unexpected ways.
When seasons change, and temperatures plummet,
water takes on its mightiest personal.
Building frozen empires,
and influencing everything in its path.
Water in its solid state even has the power
to create an entirely new species
and then turn it invisible.
(Intriguing music)
This female polar bear is conserving her energy.
She has thrived throughout the long, dark winter.
But now, as temperatures steadily rise,
her kingdom of ice is disappearing.
She needs to make the most of the frozen water
while she still can.
(Water sloshing)
Soon, the sea ice will melt away completely,
along with her hunting advantage.
(Polar bear groaning)
Even the greatest apex predators
struggle to find the motivation to get going.
But her inertia is not due to the cold.
She was born for these conditions.
(Birds squawking)
Her ancestors diverged from brown bears.
When a small population was trapped in the north
as the Ice Age descended,
they had to adapt to survive... and fast.
(Inspiring music)
Over the next 500,000 years,
the frozen realm gradually transformed those brown bears
into the polar bears that now roam the far north.
The iconic Arctic residents we see today
are the result of one of the fastest evolutionary changes
amongst all mammals.
To endure the deep freeze,
wandering foragers became masterful hunters.
Forged by ice and guided by instinct...
lumbering land animals were streamlined
to fit their new semi-aquatic lifestyle.
(Water splashing, polar bear groaning)
(Gentle music)
And to combat the cold,
extra layers of fur grew with a crucial additional feature.
Each hair has a hollow core, offering life-saving insulation.
As a result, their ancestral brown fur lost its pigment
and turned translucent.
Blending in seamlessly with their winter wonderland.
Now, having perfectly evolved to a life in the Arctic,
this polar bear needs the sea to freeze over
so she can use the ice as a platform
for hunting her primary prey.
But as it begins to fracture,
just finding food is a monumental challenge.
She may have to swim hundreds of kilometres in search of a meal.
Until finally, she picks up a scent.
A bearded seal hauled out on an ice floe.
The melting ice means her journey across the sea
may be more unstable.
But it also offers her the opportunity for an ambush.
(Water splashing)
(Tense music)
Her sleek shape makes her an efficient swimmer,
with her huge paddle-like paws pushing her silently
through the water.
She can't risk being spotted.
Her smooth movements mimic the floating ice.
Silently, she fully submerges in the water...
..and swims under the ice...
..for the ultimate sneak attack.
(Dramatic stinger)
(Splashing)
Even an ice queen can't win every time.
(Polar bear panting)
With one shake of her water-resistant fur,
she'll be dry in no time.
(Gentle music)
Every failed hunt costs her valuable energy,
and time is running out.
When summer peaks, most of her ice will disappear,
and she'll be forced to return to dry land.
Left to scavenge whatever scraps she can find
until the freeze returns.
This seasonal thaw brings hardship for the polar bears.
But every year, it is this great melt
that breathes life back into the Arctic,
igniting an entire food chain.
(Enchanting music)
For much of the year, the Arctic is a frozen wilderness.
But beneath the ice lies a hidden secret...
waiting for the sun to unlock its potential.
After the darkness of winter, spring approaches.
It's still well below freezing,
but the daylight hours are getting longer,
and the sun's force is increasing.
Then a pivotal moment arrives...
..and the balance is tipped.
The sun's power becomes just strong enough
to set off a chain of events
that will bring new life to the Arctic.
(Mesmerising music)
Underneath the sea's frozen surface,
the ice has been stained green by algae, a tiny marine plant
that has lain dormant throughout the winter.
(Clouds whooshing)
As the sun's rays start to penetrate the ice...
..it awakens the algae.
Like all plants,
they use photosynthesis to turn sunlight into food.
And now, there's just enough of it
to kick the algae into action,
which in turn, stirs another creature from its winter torpor.
The Copepod.
These tiny marine crustaceans, just two millimetres long,
rise up from the depths.
(Water bubbling)
Despite their diminutive size,
these creatures are the key to all life in the polar regions.
They devour the algae in their millions.
This transfers the sun's energy to the copepods...
..where it's stored in their bodies as a fatty oil.
Now, locked beneath the ice within the copepods,
lies a store of pure bottled sunshine,
waiting to be released.
(Joyful music)
Above the water, the sun continues to melt the surface ice...
..slowly unlocking the pantry door.
(Water sloshing) Fish are the first to arrive,
to feed on the abundant copepods.
Followed by Arctic seabirds.
(Birds squawking)
(Majestic music)
And then, the largest predators join the feast.
The sun's life-giving energy now flows throughout the food web,
all triggered by the Great Melt.
This explosion of life will fuel the Arctic residents
during the summer months,
until the big freeze returns
and the waters fall silent once again.
(Sombre music)
Frozen worlds can rise
and fall with the changing temperatures.
(Snow pattering)
But when the snow arrives early,
being caught in last season's wardrobe could be fatal.
(Intriguing music)
It's late autumn in Norway.
Among the changing leaves of the forest,
this stoat is prepping for winter.
He doesn't hibernate
but needs to store some emergency rations, just in case.
He has time.
Highly attuned to the dwindling daylight hours,
his internal clock will warn him when change is coming.
(Gentle music)
But this year, winter arrives unseasonably early...
..taking everyone by surprise.
(Enchanting music)
And it seems some creatures like surprises.
(Playful music)
As fun as it is, there is a problem.
The early snow has caught the stoat unprepared.
(Ominous music)
As he ventures out to look for food,
his brown fur stands out against the white,
making him an easy target for his greatest foe.
The golden eagle.
He needs a costume change.
Stoats have the remarkable ability
to turn completely white in winter,
to blend in with their changing surroundings.
But it's not the arrival of snow on its own
that triggers the change in colour.
It's actually the length of the day.
As the days shorten, he produces more melatonin,
which changes the way his fur grows.
(Stoat pattering)
Meaning his transformation is usually perfectly timed.
(Curious music)
But now, the sudden change in weather
sends the melatonin within his body into overdrive,
speeding up his moult.
First, he waits for the thicker white hairs to grow...
..before he sheds all of his brown fur.
While he moults, he's neither one colour, nor the other.
So he needs to remain wary.
Oops, still not quite ready yet.
A few days later...
..his makeover is complete.
As white as pure snow.
And hard to spot.
He's even changed his name.
Now, he's known as Ermin.
He still has the black tip to his tail.
This acts as a useful decoy for predators, so he's keeping it.
Now fully camouflaged,
he can safely continue his search for food.
Snow can influence coat colour throughout the Arctic.
But could winter white be going out of fashion?
(Gentle music)
The ice worlds of our planet's wild north have helped create
one of nature's most charismatic shapeshifters.
The Arctic fox.
Like the stoat,
this female has already changed her coat for winter.
She is equipped for survival
in the most changeable of environments.
As the frozen brown earth of the tundra turned white,
so did she.
Becoming a ghost in the snow.
(Wind howling)
(Delicate music)
The ice and snow have demanded a thicker winter coat,
to protect her against temperatures
as low as minus 50 degrees Celsius.
(Harsh wind gusting)
But winter brings other challenges.
The snow that conceals her also buries her prey.
Finding food beneath layers of ice and snow takes...
..a different approach.
(Wind whistling)
No luck today.
But this hunter is also happy to scavenge.
The border where the tundra meets the unfrozen sea...
..brings new opportunities.
(Waves crashing over gentle music)
She scours the beach.
The ocean never fails to deliver tasty morsels
to this shoreline, whatever the season.
But she's not the only one looking for leftover seafood.
Another Arctic fox.
A perfect shadow of herself.
Despite the snowfall, this fox never turns white.
He's what's known as a blue morph.
He's the same species,
but a genetic mutation means his coat only ever turns
different hues of a grey-brown colour.
This is his domain,
and he's not one for sharing.
She'll have no luck on this stretch of beach.
In this salty habitat, snow rarely lingers.
Her white coat,
which camouflaged her so well on the tundra,
now works against her.
(Pensive music)
Whereas the blue morph's colouring,
tailormade for this ice-free environment,
gives him a unique evolutionary edge.
And the numbers of his kind are on the rise.
As climate change increasingly disrupts nature's calendar,
white might no longer be the most fitting colour here.
By living near the sea, where saltwater melts snow,
the blue morph fox has inadvertently prepared itself
for a future where snowfall could become more unpredictable.
The transformative power of snow is extraordinary.
The collective force of trillions of individual ice crystals,
each one uniquely crafted.
(Enchanting music)
As water freezes, the sorcery begins.
Creating long icicles...
..vast sheets...
..huge blocks...
and some of the most beautiful and delicate patterns
in the natural world.
(Ice crackling)
Snowflakes appear seemingly out of thin air.
Their fleeting, ephemeral nature is what makes them so magical.
Each ice crystal is a one-of-a-kind phenomenon...
..shaped by its origin story.
(Clouds whooshing)
It all begins high in the atmosphere, within a cloud.
When water vapour encounters frigid temperatures,
the individual droplets cling to a microscopic dust particle
found floating in the air...
..and start to freeze.
(Twinkling music)
And as each dust particle is shaped differently,
so are the foundations of every snowflake.
More water molecules then freeze around this core,
creating the framework for a tiny ice masterpiece.
It extends outwards...
..naturally forming a six-armed lattice -
the snowflake's signature shape.
Each branch lengthens with every minuscule addition of water.
Its intricacies fashioned by subtle variations.
Dancing within its cloud, it encounters pockets of air
with different temperatures and densities,
which also influence the snowflake's form and design.
Some grow slender needles.
Others bloom into star-shaped crystals.
By each taking a different journey,
their identities are finessed into something unique.
It takes a billion billion water molecules
to make a single snowflake,
sculpted in just fifteen minutes of fleeting magic.
(Enchanting music)
As they continue to grow bigger and heavier...
..gravity eventually wins.
Pulling them towards the Earth.
Gracefully falling together, their arms intertwine,
forming fluffy clumps of snow.
Snowflakes are one of nature's true marvels.
And when they settle, blanketing the landscape,
wildlife is forced to find imaginative ways
to escape the cold.
(String music)
Deep in the snow-covered Japanese Alps...
(Macaques chattering)
..this troop of macaques scour through the frozen drifts.
(Macaques chattering)
Food is scarce.
(Twigs snapping)
But their real prize in this frosted world...
..is warmth.
(Water rippling)
Geothermal forces beneath the Earth's surface
heat the groundwater here...
..to a balmy 40 degrees Celsius.
(Relaxing music)
This troop is the only group of monkeys in the world
to enjoy a natural spa.
A comforting bath where they can escape the winter chill.
But access to this exclusive retreat is strictly controlled.
The alpha male moves through his subjects like a king.
(Macaque chatters)
Physical strength alone secures his status.
But his partner, the alpha female,
has earned her position by climbing up through the social ranks.
For most, the water is a welcome escape and time to relax.
But not for her.
Her authority comes with a job
as the enforcer of social rank.
She holds court in the warm water,
attended by subordinates who groom her, currying favour.
At the pool's edge, the outcasts wait.
Watching, hoping for her permission to bathe.
Entrance is not a right.
It's a privilege.
Even when it's minus 20 degrees outside,
she decides who can benefit from the soothing hot water
and who can't.
All based on strict hierarchy and favouritism.
One nod, and you're in.
(Splashing)
Nearby, her partner lounges, unbothered by pool politics.
Unlike him, her power is precarious.
(Tense music)
Just one challenge to her rule, and she could lose everything.
(Macaques screeching)
(Macaques continue screeching)
So, despite the daily spa,
for her, this is the most stressful time of year.
(Water rushing, gentle music)
Order must be maintained
if she's going to keep the perks that come with the job.
But in this frozen world, it's worth it.
While these monkeys are fortunate enough
to have the luxury of a winter hot tub...
..other creatures need the force of a bulldozer
to reach their own thermal waters.
In the depths of winter,
Yellowstone National Park falls silent.
(Gentle music)
Each year, over three metres of snow
envelops this vast volcanic landscape.
Its sprawling forests and plains transform,
now locked in a deep freeze.
For the wild residents, life grinds to a halt.
(Mountain goat bleating)
Food vanishes.
Trails disappear.
Leaving many stranded.
There's only one group of municipal workers
who can get this snowbound town up and running again.
(Country music)
Bison are nature's snowploughs.
This female is the leader of the convoy.
Her job? Creating roads in the snow.
Broad and muscular, driven by powerful neck muscles
and extra long vertebrae,
she ploughs through even the deepest drifts.
(Wind whistles, bison huffing)
With every swing of her head, she uncovers buried treasure,
grasses locked beneath the snow.
(Bison grunting)
And as they clear the snow to graze,
their tracks become Yellowstone's winter highways.
Benefiting the community...
..coyotes eagerly follow the trail.
And deer nibble vegetation exposed by the bison.
And smaller inhabitants can roam again.
The matriarch drives her way
towards Yellowstone's geothermal basins.
(Bison grunting)
Here, The Earth's heat melts the snow,
revealing expansive grasses and mineral rich soils.
(Enchanting music)
Other bison herds gather,
heading towards the volcanic warmth.
Together, they are the caretakers of this wilderness.
Along with snow clearing,
their grazing and scattering of nutrients
leave behind a healthier ecosystem.
Come spring, thanks to their work,
bison grazed areas will regrow faster and stronger.
But there are other giants made of ice
that leave their stamp on the landscape
on a much grander scale.
(Intriguing music)
Glaciers have been weaving their magic across our planet
for billions of years.
Shaping everything in their path.
These slow-moving rivers of ice
flow to the rhythm of a deeper passage of time,
sculpting the land on their relentless march onwards.
They are the largest moving objects on the planet
and keepers of 70 percent of Earth's fresh water.
Gravity slowly propels them downhill.
Gouging out lakes and valleys in their wake.
(Awe-inspiring music)
Their faces tell the story of their long lives.
A tapestry of dark deposits reveals their journey
through land and time.
While their jagged spines chronicle a lifetime
of melting and refreezing.
(Wind gusting)
(Magical music)
In contrast,
their rarely seen underbelly is as smooth as glass.
Over eons, the glacier's colossal weight
has slowly compressed snow layers into clear, solid ice.
Allowing light to travel deeper within its core.
Producing a luminous turquoise glow.
(Water dripping and flowing)
Some glaciers, like this one, have a hollow heart.
(Intriguing music)
When temperatures warm...
..the glacier's outer layers start to melt.
Droplets flow down through tiny cracks.
Forming streams of meltwater that bleed from their midst,
carving out glimmering ice caves.
Although glaciers have always given way to seasonal fall,
their melting is now accelerating
at an alarming pace.
(Ice and water roaring)
As the world gets warmer,
ancient waters once frozen in time...
(Ice crashing)
..start to cascade
from land, into sea.
Causing sea levels to rise...
..land to flood...
..and storms to intensify.
(Dramatic music)
These towering giants are vital to the health of our planet.
Holding fresh water locked in ice
for hundreds of thousands of years.
While many still stand firm today,
their future remains uncertain.
(Lively country music)
Ice can bring even the mightiest rivers to a standstill.
Each winter, parts of the Mississippi freeze over,
trapping the unwary beneath its glassy surface.
But one creature's demise becomes another's lifeline.
As the shallow backwaters thaw, opportunity arises.
(Bird crying)
And for one smart parent,
it's the moment they've been waiting for.
(Wings fluttering)
(Gentle music)
While late winter may seem an unlikely time to lay their eggs,
these bald eagles know better.
For this feisty Midwestern mother of two,
it makes perfect sense.
She finds it easier to keep her brood warm in the cold season
than it is to keep them cool in the heat of the summer.
Plus, there's another big advantage.
(Wind whistling)
As the frozen river cracks under the strengthening sun,
it reveals the ultimate winter bonus.
A wealth of frozen fish.
(Birds squawking)
Starved of oxygen beneath the ice,
they now float to the surface.
Perfectly preserved.
The only catch?
Every other parent in the neighbourhood
has had the same idea.
Time to get pushy.
(Birds squawking)
She can't afford to go home empty handed.
Her chicks demand 100 grams of food a day...
..each.
But as the ice continues to retreat,
more victims of the freeze rise to the surface...
..ready for collection.
(Joyful music)
This fleeting moment of abundance,
delivered by the freeze and unlocked by the thaw,
makes winter nesting a success,
as it fuels her chicks' incredible growth.
In just two months, they'll be strong enough to fledge,
ready to take to the skies...
Like their mum.
In nature, timing is everything.
Further north, a creature's imminent journey
could hold the power to shape our planet's future.
In the far reaches of Scandinavia,
the approach of snow and ice is about to kickstart
a migration on a truly immense scale.
(Reindeer grunting)
As the first flakes of snow arrive...
..it serves as a signal for these reindeer.
Over the past summer months, this three-thousand-strong herd,
mostly mothers and calves,
have gorged on these coastal pastures.
(Reindeer grunting)
But now, their real challenge is about to begin.
For over ten thousand years,
snow has dictated their winter migration.
(Uplifting music)
The oldest and wisest of the herd
will lead them across the landscape.
(Reindeer grunting)
And along the way, the influence of water in all its forms
continues to shape their destiny.
(Suspenseful music)
Norway's fjords, ice cold and up to 1300 metres deep,
hide a maelstrom of undercurrents.
(Waves crashing)
She has made this crossing before.
But for the calves, it's their first experience of deep water.
Reindeer are built for snow and ice.
But frigid, choppy water like this
poses the most serious threat.
Her instincts tell her to wait for calmer conditions.
(Reindeer grunting)
When the weather breaks...
she makes the pivotal decision
and steps forward.
The others cautiously follow her lead.
The fjord's strong currents and near-freezing waters
are still treacherous.
But reindeer are strong swimmers.
Their powerful athletic legs and wide concave hooves
propel them through the water.
(Tense music)
But the crossing is long.
As fatigue kicks in...
..the calves struggle,
their small bodies fighting the currents...
..and the cold.
(Perilous music)
The weary herd just need one last push...
..to reach the shore.
(Reindeer grunting)
This year, every member has survived the crossing.
Only another 80 kilometres to go.
(Wind gusting)
(Gentle music)
Finally, they arrive at the high plateaus, their winter home.
(Enchanting music)
Here, they can feast on the carbohydrate rich lichen
hidden just under the snow.
It's the seasonal rhythm of the Arctic ice
that guides the reindeer to these highlands.
As they travel across the vast landscape,
their appetite plays a crucial role in maintaining the balance
of not just their ecosystem...
..but the entire planet too.
Throughout the year, as reindeer graze,
they trim back grasses and shrubs,
preventing them from taking over the tundra.
Allowing snow to settle unbroken
in a shroud of pure white.
Rather than absorbing the sun's rays,
this snow blanket acts like a giant mirror,
reflecting the solar heat back into space.
Known as the Albedo effect,
this simple act keeps the Arctic cold,
which in turn creates more snow, to deflect more heat.
And when these cooler temperatures are mixed
with the warmth of the tropics,
it helps stabilise our global temperature.
(Pensive music)
It's vital that the poles retain their snow cover
for as long as possible each winter.
And driven by the ice itself,
these reindeer are playing their part.
(Majestic music)
Every step they take echoes far beyond their frozen realm
to safeguard this blue planet we all share.
(Enchanting, majestic music)
Water...
from ice...
to ocean...
is our most dynamic force of nature.
Life on Earth simply wouldn't exist without it.
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