All language subtitles for Earth from Space S01E02

From high in space,

we can see the familiar shapes
of countries...

and continents.

But now, satellite images

allow us to look closer...

revealing our planet as a patchwork

of extraordinary landscapes...

created by natural forces...

by animals...

and by us.

These patterns give an insight
into the health of our planet.

Behind every line and every pattern...

there's a story.

Around the world...

tropical coastlines are fringed
with coral reefs.

At first glance,

their shapes seem random.

But a closer look reveals a pattern...

pale discs surrounding
patches of dark coral.

Using satellite images,

scientists have now found these shapes

on coral reefs across the globe.

Understanding how they are formed

offers a new insight
into the health of our oceans...

and the animals that call them home.

For fish that live on coral reefs,
there are different strategies

for finding food.

Some stay close to the reef...

feeding from the coral itself.

Others venture out

to the surrounding seabed.

But feeding in the open...

can be dangerous.

Predators, like coral groupers...

and sharks,

patrol the reef perimeter.

So small fish only feed
as far from the coral

as is absolutely necessary...

staying within easy reach of safety.

Over time, the seabed around
each patch of coral is stripped of food...

creating rings of bare sand

that scientists call grazing halos.

They are a sign that both predator
and prey populations are healthy.

But where this pattern disappears,

it may be a sign
that predator numbers are falling.

These halos now allow scientists

to monitor the reefs'
delicate balance from space.

Satellite cameras can now look down
on every part of our planet...

allowing us to explore
Earth's most remote habitats.

The Congo jungle in central Africa.

This forest is home
to thousands of animal species.

But from space, it appears as
little more than a blanket of green...

except, that is, if we look down
over one remote corner.

Satellite images reveal a strange shape...

with dozens of trails leading in
from the surrounding forest.

This shape was created
by the Congo's mightiest residents.

They spend most of their lives
hidden in the thickjungle...

but travel hundreds of kilometres
to gather here.

Forest elephants.

Locals call this place Dzanga Bai...

the Village of Elephants.

Forest elephants spend most of
their lives in small family groups.

But here, up to 150 individuals

are drawn together every day.

Their diet of tough leaves and
jungle fruit is lacking in vital minerals.

So generations of elephants have come
to this one spot in the forest...

where deposits of sodium,
potassium and calcium

lie just below the surface.

Using their tusks to dig at the soil

and their trunks to blow into the water...

these elephants have excavated
a network of boreholes...

allowing them to extract these minerals
from underground.

Over hundreds of years,
the constant digging

and movement of elephants
has caused this clearing to grow.

It's now more than 500 metres long...

and clearly visible from space.

For a young forest elephant,
a first visit to the Bai

is full of new experiences.

While the adults drink effortlessly...

she's still getting to grips
with her trunk.

Infants are raised by their mothers
for up to four years...

and learning how to drink
from these wells

is one of life's vital lessons.

For a calf who spends most of
her time with her mother...

this is a rare opportunity
to socialise.

Relationships formed at this young age
can last a lifetime.

But while they play...

mothers must keep a close watch.

Male forest elephants are also drawn here.

This gathering is the ideal place
to find a fertile female.

To display their size and strength...

bull elephants
charge around the clearing.

And if more than one male appears...

tensions run high.

Young forest elephants have been
killed here by charging males.

Mother retreats
to the safety of the forest.

Her baby should be able to return
to this clearing throughout its lifetime.

But these elephants
face an uncertain future.

In the last 20 years,

more than half of all the forest elephants
in the world

have been killed by poachers
for their ivory.

But cameras in space
may be able to help.

Scientists can now use satellite images

to identify other clearings
used by forest elephants...

protecting them from poachers...

and preserving these unique gatherings.

But you don't need to be
as big as an elephant

to make a mark visible from space.

In South Australia...

the outback is speckled
with mysterious light patches...

interlinked with narrow trails...

the work of an unlikely architect.

He's a southern hairy-nosed wombat...

a marsupial only found
in this part of Australia.

Exposing the thinner fur of his belly

helps to keep him cool as he waits
for the midday heat to pass.

Then there's work to be done.

It's springtime,

and with each passing day
temperatures are steadily rising.

In just a few weeks,

it could be close to 5O degrees Celsius.

Wrapped in a thick fur coat,
this heat could be deadly.

But the wombat has a solution.

With sharp claws
and short, powerful limbs,

he's built for digging.

It's 15 degrees cooler below ground...

a hiding place from
the worst of the summer sun.

But high temperatures aren't
the only threat wombats face.

Habitat loss and the impact
of invasive species

caused wombat numbers to plummet
in the early 20th century.

But now, using satellite images
to locate their burrows...

scientists can see
they're bouncing back...

with around one million
southern hairy-nosed wombats

now living in this corner of Australia.

In South America,

vast areas are covered with
lush, green tropical forest.

But on the coast of north-east Brazil,

the forest is interrupted
by a very different landscape.

Vegetation is being
swallowed up by sand.

Washed up by the ocean and blown inland
over thousands of years...

a field of sand dunes covering
more than 800 square kilometres.

The Lengéis Maranhenses.

The surface of the scorched sand

can reach 80 degrees Celsius.

To survive here you have to
be made of tough stuff.

A Pininga turtle.

She's left the surrounding forest
behind...

and is making her way
into the heart of this desert...

walking for days

beneath the burning sun...

each step on the soft sand
sapping away her precious energy.

Without food and water,
she won't survive for long.

But she's made this journey for a reason.

It's the wet season.

And in these dunes,
the rain changes everything.

Only from space can we see
the scale of the transformation.

Once a year, rainwater
floods the desert...

forming thousands
of freshwater lagoons.

Beneath the sand, a layer of solid rock
stops rainwater escaping...

creating a landscape

like nowhere else on Earth.

And that's just what she came for.

As the lagoons grow,

fish make their way into the pools
from surrounding rivers.

They'll keep her fed for weeks.

But this water won't last forever.

In the tropical sun, these lagoons
will soon evaporate.

Dozens of desert species now race

to make the most of
the life-giving water...

even after the sun has set.

A tiny four-eyed frog.

He's been lying dormant in the cool sand.

But the rains have triggered
the breeding season.

And there are thousands just like him.

In other parts of the world,

frogs migrate for kilometres
to reach their breeding pools.

But here, the water has come to them.

Around the lagoons,
grasses have sprung up,

creating sheltered spots for breeding.

And it's not only four-eyed frogs
who come here.

Seven different species of frogs and toads

are all hoping to breed.

It's a struggle to make yourself heard
above the noise.

Eventually, the four-eyed frogs
find each other.

Each pair may produce
more than a thousand eggs...

an explosion of new life.

And just in time.

When the rains ease,
the lagoons begin to disappear...

and sand reclaims
this corner of Brazil.

Around the world, the forces of nature

create mysterious and intriguing patterns

visible only from space.

Star-like shapes in the Sahara desert

are sand dunes whipped up by the wind.

In West Africa, a ring
of concentric circles...

formed by magma forcing its way
through the Earth's crust.

And in Iran's salt desert,

these abstract swirls are the remains
of an ancient ocean...

sculpted by the wind
over millions of years.

In the Amazon rainforest, hundreds
of rivers wind through the jungle.

Alongside them

are strange arcs and horseshoe shapes.

Satellite images taken over 30 years
reveal how these patterns are formed.

As the water forges a path
through the jungle...

bends in the river are cut off
and left behind...

creating isolated oxbow lakes...

like El Dorado Lake in northern Peru...

a special place for wildlife

and for local people.

Elvira is nine years old.

She and her friends
live in a small village

close to the oxbow lake.

They're fascinated by animals...

and their favourite
is perhaps the most elusive...

the Amazonian manatee.

Manatees spend their lives hidden
in the murky water of jungle rivers...

surfacing only briefly to take a breath

or to feed on floating plants.

In many parts of the Amazon,
manatees are hunted for their meat,

and their numbers are declining.

Elvira has never laid eyes on a manatee.

Va mos, chicas!

But that's all about to change.

The oxbow lake has
all the benefits of a river...

but its isolated waters
are still and safe...

perfect for manatees
in need of a second chance.

For Elvira, it's an opportunity

to finally come face to face

with her favourite animal.

This manatee is one of a lucky few.

They were rescued from illegal captivity
and rehabilitated

by an international team of experts.

They're now fit and well enough

to be released.

Radio tags will allow their progress
to be monitored...

as they start their new life
in the safety of the oxbow lake.

The twists and turns
that lead to oxbow lakes

are typical of slow jungle rivers
meandering over flat ground.

But across the globe, each river

has its own unique character.

In Egypt, the River Nile
brings life to the desert...

creating a ribbon of green.

At the base of the Himalayas,

the Brahmaputra River pulls in water
from hundreds of streams

pouring out of the mountains...

creating a complex channel
ten kilometres wide.

In the USA, the movement
of Utah's Green River

has carved out deep canyons
over millions of years.

In eastern China...

five major rivers converge...

to form a body of fresh water so huge

that the only way to see it
in its entirety is from space.

Poyang Lake.

This is no ordinary lake.

Each year, when the dry season arrives...

it begins to shrink.

Within three months,
it almost totally disappears...

leaving behind huge areas
of nutrient-rich mud...

and hundreds of
shallow freshwater pools.

This transformation is the cue

for one of the greatest migrations
on our planet.

Half a million birds flock here
from all across Asia.

But none have travelled further

than the critically endangered
Siberian cranes.

This is the end of a month-long journey
from northern Russia,

almost 5,000 kilometres away.

They've come for
a unique feeding opportunity.

The falling water has revealed
the nutritious roots of aquatic plants.

The cranes gorge themselves
after their long journey.

And they aren't interested in sharing.

Among the many families

are two parents with
their five-month-old offspring.

He's successfully completed
his first migration.

But 5,000 kilometres was a long way to fly

on young wings.

He begs for food.

But his mother...

ignores him.

It's every bird for themself.

And from space,

it's clear to see why.

As the dry season progresses,
the pools shrink...

increasing competition
for the best feeding spots.

A rival has strayed
onto the family's patch.

This cannot go unchallenged.

Father squares up to the intruder.

Neither is willing to back down.

Their claws are razor-sharp.

15-centimetre-long beaks

become weapons.

The intruder...

is seen off.

But the youngster still hasn't
been able to get a meal.

There's only one thing for it.

He finally works out
how to feed for himself.

The whole family can now fuel
themselves up for the return journey

to Siberia.

After four months, the rivers that flow
into Poyang begin to rise again...

and the cranes start
the long flight home...

an epic journey...

triggered by a remarkable
transformation.

The coming and going of water

makes for some of the most beautiful
landscapes on Earth.

Rivers arriving at the coast

deposit vast quantities of sediment...

creating deltas that reach out
into the ocean.

In northern Russia,

the Lena River forks into
thousands of separate channels.

And in the Gulf of Mexico,
the Mississippi River Delta

spans 10,000 square kilometres.

But the largest delta in the world

lies in the Bay of Bengal.

This maze of waterways

is the Sundarbans.

Twice a day, it's transformed
by the tide...

blue...

to brown...

as the tide falls,

exposing the mud below.

Silt from river water is
trapped by mangrove roots...

creating a habitat like no other.

A home for timid chital deer...

troops of macaques...

elusive Bengal tigers...

and over three million...

Pe0ple.

Bhoben and his son Hridoy live

in the north of the Sundarbans.

Bhoben is a fisherman.

He's teaching his son the family trade.

But they won't be fishing
with lines or poles.

Instead, they'll be using

ten smooth-coated otters.

The people here have been fishing
together with otters

since the sixth century.

Wild otter populations
are declining in the Sundarbans.

This specially bred captive population
could be crucial

for the survival of the species.

And they're extremely precious
to their owners.

But they can only fish
at very precise times of the day.

They have to wait for the tide.

While it's high,

thousands of tiny inlets
crisscross through the mangrove forest.

Water dominates the landscape,

giving fish plenty of places to hide.

But from space,
we can watch the tide turn.

Water is replaced with mud.

And at the very lowest tide,

fish are forced into the few
remaining stretches of water.

And the otters get to work.

Their sensitive whiskers
detect the movement of fish...

and they flush them towards the nets.

Young otters swim freely.

They're supposed to be
learning from the adults,

but it's easy to get distracted.

The otters bring in up to twice as many
fish as using nets alone.

And they take their cut.

Ten otters can eat
eight kilos of fish every day.

But it's getting harder
for fishermen here to make a living.

Large-scale fishing
and pollution from growing industry

are decimating the fish stocks
in the Sundarbans.

From over 200,

this is nowjust one of eight boats
keeping this ancient skill alive.

The tide turns,

and the fishermen follow the water home.

Humans have always found
ways to survive

alongside our planet's natural landscapes.

But around 10,000 years ago,

we began to create patterns
of our very own.

Alongside nature's chaotic curves,
more ordered shapes appeared...

designed with great precision...

to help us feed ourselves.

At first, farming could only take place
alongside natural water sources.

But now, even in the driest desert,
crops are being grown.

And one shape has come to dominate.

By using rotating sprinklers,

farmers can water a circular field
more easily than any other shape.

In the American Midwest,

these irrigation circles
stretch for hundreds of kilometres.

Intensive farming like this
can force out wildlife.

But no matter how tightly
circles are packed together...

there'll always be gaps
left between them.

In Missouri, farmers are encouraged
to keep these spaces wild...

creating pockets of habitat
for animals...

like the bobwhite quail.

On the edge of this circle,

just enough space has been left
for quail to raise their chicks.

With hungry new mouths to feed,

families are always on the move
in search of food.

Young chicks are inquisitive -
keen to explore their new world.

But in the thick undergrowth,

parents can find it difficult
to keep an eye on all of them.

And there are others here

looking for a meal.

Kestrels have their own young to feed.

Mothers know the best thing to do

is hunker down and stay still.

But a lone chick's instinct

is to keep running.

She's inside the circle of crops.

An alien world.

Row upon row of soybeans

arranged in a circle
almost a kilometre wide.

There's nothing to eat

and, in the height of summer,
nothing to drink.

Dry conditions are bad for the crops, too.

But here in Missouri,
they have a solution for that.

Millions of gallons of water
pumped from deep underground...

and piped along a rotating arm
300 metres long.

A life-saver for the crops...

but potentially deadly
for a quail chick.

Life beside industrial farming
comes with dangers.

But each small patch of wild habitat

can be an important oasis for animals.

There are now 125,000
circular fields in the USA.

Who knows what dramas may be unfolding
in the spaces left between them?

Human agriculture now covers more than
one third of the Earth's land surface.

Add to that the space taken up
by our homes and our industries

and humanity's impact can now be seen
on more than half of the planet's land.

For millions of years, natural forces
have shaped Earth's surface.

But now, it is undoubtedly us
who will decide

what our home will look like
in the future.

Next time...

The view from space
reveals our blue planet

as a kaleidoscope of incredible colours.

Vast turquoise swirls in the ocean

trigger the planet's
biggest feeding frenzy.

Billions of flowers turn
a Chinese landscape bright yellow.

And a lake in East Africa is transformed

by the pink of thousands of flamingos.

Each colour has its own
remarkable secrets to reveal.