CHD Lee-king
Of all the planets in our universe,
there is only one we know can support life.
just the right distance from its sun with a perfect climate.
lt's been called the lucky planet.
About five billion years ago, a huge asteroid crashed into Earth
tilting it at an angle of exactly 23 and a half degrees to the sun.
This cataclysmic accident turned out to be nothing short of a miracle.
Without that crucial tilt,
everything would have been different.
For it created the seasons, the extremes of climate, hot and cold,
and landscapes of spectacular beauty.
The perfect conditions for life on Earth.
January, the high Arctic,
and there has been no sun for over a month.
At this time of year, it's permanent night.
Male polar bears are on winter patrol, but there is little to eat.
Every living thing is just waiting.
March,
and the sun makes its first appearance over the horizon.
This female bear has been underground in her den the whole winter.
She toboggans down the slope.
Perhaps it's just to clean her fur,
but it looks like sheer joy.
She hasn't been alone down there.
Her cubs were born underground.
They're two months old,
but this is the very first time they've seen the light of day.
since they were born deaf and blind beneath the snow.
The cubs haven't been fed this morning.
The mother has delayed their first meal on this special day.
Hunger will draw them to her.
lt's the beginning of their training.
Milk is the only food the cubs have known
The mother hasn't eaten for five months,
and has lost half her body weight.
She's giving the last of her reserves to her cubs.
Every year at this time, female bears need food desperately.
They know they must get down to their hunting grounds on the ice.
What they can't know, is there's a problem waiting for them there.
our planet is warming and the sea ice is melting earlier every year.
This is the only place the bears can hunt for seals.
lf they don't make it there before the ice breaks up,
their families will starve.
So far this year, the ice holds firm,
firm enough to support the male polar bear, the father of the cubs,
as he searches for his prey.
He won't help the female.
lnstinct makes him fend for himself alone.
Ten days later,
and the starving mother is trying to lead her young down to the sea ice.
They've found their feet now,
but they still don't share her sense of urgency.
At last, everyone seems ready for the journey,
but it may already be too late.
A few miles from the coast, the ice is already breaking up.
She is leading them into an increasingly dangerous new world.
lt's unlikely both of her cubs will survive their first year out on the ice.
The ice is become too thin to support the weight of cubs father,
Glacial melt waters pour from the land, mix with the sea, and speed up the thaw.
Each year, as the climate warms, there is less and less ice in the Arctic.
This is a disaster for polar bears.
Without a solid platform, they father will struggle to hunt the seals he need to survive.
Far the south,the melting snows reveal lot vast expense of arctic tundra
Visitors flock to this haven from all over our planet.
They've come to make the most of the brief flush of spring food
and to have their young.
Caribou travel north following the form -
more than three million in vast herds crossing the tundra.
Some herds travel more than two thousand miles every year
in search of fresh pasture.
lt's the longest overland migration on Earth,
They are constantly on the move.
lf newborn calves are to keep up,
they must be on their feet and running the day they're born.
but these vast herds don't travel alone.
Wolves shadow them all along the way... and they're hungry.
At first, the attack seems random,
but this running of the herd is a tactic to generate panic.
ln the chaos, the young can be separated from their mothers.
Now it's easier to target an individual calf.
By this stage, the odds are even.
Either the caribou will make a mistake,
or after a mile or so, the wolf will give up.
Mid summer on the tundra
And the sun does not set
There are no trees here
To find the first woodland
We must travel much further south
This stump to chops, mark the tree line of our planet and the start of the Taiga Forest.
This vast belt of trees forms an almost unbroken circle around the north of the globe.
lt's one of the last great wildernesses.
These conifers have needle-shaped leaves -
virtually inedible -
so the forest supports very little animal life.
ln this silent world, the snow is rarely marred by footprints,
and those who do live here are so hard to glimpse, they're like spirits.
The lynx roams hundreds of miles in search of prey.
lt may never visit the same patch of forest twice.
This creature is the very essence of wilderness.
There are as many trees here as in all the world's rain forests combined -
one third of all the trees on Earth.
As spring creeps up from the south, the Taiga is unveiled.
With this transformation
oxygen level in the air we breath rise over our planet
And the further south we go on our journey
The meddle sun works its magic
Summers are longer here and deciduous trees can flourish.
They're far more edible than conifers,
so these forests bustle with life.
Spring has also come early for the mandarin ducks.
The female is leaving her nest high in the treetops.
lt's her job to lead the way.
lt's a long way down for a maiden flight.
A few calls of encouragement are needed here.
There are still two missing.
This is the legacy we've inherited,
thanks to that all-important tilt of the Earth's axis -
the rhythm of the seasons.
The transformations of our world year on year,
Then the challenge is winter
Here,in the broadleaf forest Russia
Winter can be impeccably hard
The Amur leopard
Where it's cat in the world
Her cub is a year old
And still depend on it's mother
There are fewer then fourty amur leopad left in the wild
They been hunted almost extinction
And the harsh winter here, in the that recovery
There are a parts of our world that have no seasons.
Here in the tropics, the sun shines for 12 hours a day,every day
And so the jungle grow unchecked all year arround
and support so abundance of life.
Rainforest now covers a third of the area it once did -
and yet, it contains more than half of all the plants and animals on Earth.
The rain forests of New Guinea are especially precious -
home to 42 different kinds of birds of paradise,
each more extraordinary than the last.
This is a particularly rich forest,
so the six-plumed bird of paradise has no problem finding food.
He can concentrate on more important tasks,
like tidying up his display area.
He's obsessed with housework.
Everything has to be spick and span.
Finally, the stage is set.
This contender is called the superb bird of paradise.
This magician has a special trick.
First, he advertises his show,
calling to attract a female.
And he has more luck
She just has to have been impressed with that.
She retires a little way off to consider her verdict.
After all that effort, can she still have doubts?
You can't help feeling deflated when even your best wasn't good enough.
These tropical forests not only enjoy 12 hours of sunshine all year round,
but also we see more rainfall in anywhere else on earth
Without so much fresh water the jungle will not grow
Deserts cover one third of the land's surface on Planet Earth,
and they're getting bigger every year.
This is a land where only few can survive -
The Kalahari Desert in Southern Africa.
lt's the dry season here,
and thousands of elephants have started the desperate trek for food and water.
All are making their way to the Okavango,
a vast inland delta in the desert.
At the moment it is dry, but water should come.
Buffalo join the great trek.
All across Southern Africa, millions of animals are on the move,
on the same life or death quest for water.
This tiny calf struggles to keep up.
lts mother's instinct is to care for it,
but her need for water is so desperate,
she may be forced to leave it behind.
Dust storms make the going tough all the way.
They've become separated from the herd.
This is a dangerous place to lose your way.
There's sanctuary a few miles ahead - a small patch of woodland.
They daren't rest until they reach it.
The main herd has aleady arrived the safety
Finally, the stragglers emerge from the dust.
Blinded by sand, the calf barely has the strength to go on.
The storm has died down.
but not all the animals have been so lucky.
One youngster got lost.
Thirsty and exhausted, it follows the tracks of its mother, but in the wrong direction.
Where dust meets water,life return.
Sand dunes give way to prairies and savannah.
Grass is a great unsung hero of our planet.
lt keeps deserts in check and fuels many of Earth's great spectacles.
Every day on wide open plains the world over,
a timeless ritual plays itself out -
the drama of hunter and hunted.
The elephants have been marching now for two weeks.
The little calf and its mother have caught up with their herd,
but they're desperately thirsty now.
Perhaps spurred on by a memory from the past,
the matriarch leads the herd to a temporary water hole -
one that may have saved her life years ago.
The elephants have to share the water with others.
These are uneasy alliances.
By day, the elephants dominate the water hole.
ln the night time, the balance of power shifts.
The calf and its mother are most at risk.
They're closer to the lions than they can know.
ln the darkness, an elephant's vision is little better than our own.
Lions can see easily.
The lions bide their time.
lt's the calves they're after.
As the lions rally, the elephants herd their young together,
forming a protective circle to keep them away from the predators.
Normally, a solitary lion would stand no chance against this elephant,
but the whole pride is here - 30 of them -
and they're specialist elephant hunters.
There are more dangerous in the long road ahead
the Okavango Delta is still many miles away.
The sun that scorches the air also brings water to the desert.
As it beats down on tropical seas,
moisture rises from the warming oceans powering our global weather system.
Moist winds from the Indian oceans sweep north towards the Himalayas.
As the air rises, so it cools and the water falls as snow.
The scene is set for one of nature most challenging migrations.
Each year, thousands of demoiselle cranes try to escape the harsh winters in Mongolia,
by flying south to the warmer climes of lndia.
To get there, they have to cross the highest mountain range on Earth,
the Himalayas.
As the sun heats these great slopes, warm air rises from the valleys,
turning, by late morning, to ferocious winds.
The cranes hit violent turbulence.
They'll have to turn back or risk certain death.
The sun's rays weaken in the afternoon and the turbulence falls away,
but it's too late for today.
A new day, a new chance to a tame hazardous trip.
lt's early morning and the warm air is already rising fast.
They use the thermals to gain height.
Soon it'll get stormy again, maybe too stormy to go on.
ln the final ascent, every wing beat is a desperate battle against the freezing winds.
At last, they've made it. They've conquered the highest peaks on Earth.
On the other side there's sanctuary for the winter.
The sun raise melts the snow and the waters go on their way again -
This is the great unending cycle.
sunlight and fresh water bringing life to every corner of Planet Earth.
After months of drought, the rivers begin to flow again in the Kalahari.
The buffalo reach the end of their long journey.
As the water sweeps through desert lands,
the Okavango is transformed into a fertile paradise.
This is an Africa we rarely see -
a lush water world
Many animals are quite at home in the flood,
but there are some more apprehensive bathers.
After weeks of marching, the elephants are exhausted.
They struggle to stay focussed on the road ahead.
The matriarch can smell the water,
and encourages the herd to make one last effort.
After so many weeks,
many hundreds of miles,
they've arrived.
like the polar bears the lives easy elephants dominat by the sun
it's driver,is annual cycle of weat and dry
Just it dose for the land the sun fuel lives in the oceans.
This calf is no more than a few weeks old
and as he begins to tire,
his mother supports him close to the surface, so that he can breathe.
These shallow equatorial waters make good nurseries -
they're warm and calm and there are few predators.
The playful calf is now drinking 600 litres of milk a day,
but its mother is starving.
There's nothing for her to eat in these crystal clear waters.
To find food, she will have to lead her calf on an epic 4,000-mile journey
to richer feeding grounds at the southern extremes of our planet.
Out in the big blue, dolphins are closing in on their prey.
A hundred sailfish join in the attack.
Reaching almost 70 miles an hour, they are the cheetahs of the sea.
Mother and calf swim on south through the vast open oceans.
They have to cross half the globe,
from the equator all the way to the edge of Antarctica.
The tropical seas are a long way behind them now.
And they're heading for stormy weather.
Winds and currents stir the water draw nutrients up from the depths
life blooms wherever the sun's rays can penetrate.
The great white shark.
harp seal are the victims today.
The whales are 3,000 miles from the equator.
And the waters are getting colder and rougher.
Mother and calf must stay close.
So as not to lose track of each other, they slap their fins on the surface.
They can hear these sound signals above the roar of the ocean.
As the sun melts the ice, life returns to the Antarctic Peninsula.
The whales reached the far south at last in time for the summer.
Adelie penguins...
and they're in a hurry
The Antarctic summer is all too short,
but for a few brief weeks the sun will not set
its warmth unlocks sheltered bays
ln the depths, something stirs.
At last, after their 4,000-mile journey, the humpback whales can feed.
They harvest krill, shrimps that begin to swarm here as soon as the ice retreats.
Now, at last, the mother can replenish her reserves
as she and her calf join the rest of the team.
The whales create a spiralling net of bubbles,
concentrating the krill into one gigantic feast.
They work round the clock, for the boom will be short-lived.
Summer is already fading
they'll soon have to swim all the way back north,the tropical waters.
The greatest seasonal change on our planet is underway.
The sun begins to retreat from Antarctic.
Soon the continent will be plunged back into darkness.
The Aurora Australia illuminates the southern skies,
but these spectacular lights bring no warmth to the wilderness of ice.
In the north of the planet, where our journey began,
it's hind summer now
our polar bear's ice world has completely vanish.
lf he doesn't find land soon in this vast ocean, he will drown.
After many days at sea,
the exhausted male bear is drawn by the pungent smells of the colony.
He has lost half his body weight.
He's desperate for food,
but walrus are munch larger than his unseal prey.
lt's the pups he'll have to get to.
The powerful adults can do terrible damage with their huge tusks.
He may be the world's biggest land carnivore,
but it looks like he's met his match and he's badly weakened by starvation.
A pup hides behind its mother.
lf he can just prize her off.
With the herd retreating to the safety of the water,
the bear has little time left.
He tries again.
And again, in sheer frustration now.
He has to avoid the lethal tusks at all costs.
lt slips from his grasp.
lt's only when bears are on the verge of starvation
that they'll risk attacking such dangerous prey.
This one took the gamble...and lost.
The walrus are calm again.
The bear is no longer a threat.
Unable to feed, he can't survive.
As the global climate continues to warm,
and the arctic ice melts sooner every year,
more of his kind will come to this sad end.
The polar bear has become an emblem for the state of our planet
and for all the creatures who are struggling to live alongside us.
Finally, we've begun to understand
how precarious is the state of our once lucky planet.
lf we are to go on sharing Earth with such a rich variety of life,
and preserve its fragile balance for our own children,
now, more than ever...
it is in our hands.