Original subtitles

Narrator: they're watching you.

More than 4,000 satellites Circle the earth.

Every day, they uncover New mysterious phenomena.

Some defy explanation.

Bam! This sticks out Like a sore thumb.

That's is the strangest Thing going.

Narrator: a black mark darkens The desert in war-torn iraq.

What the heck is going on? It looks completely scorched.

Narrator: a moving wall of ice Causes terror in the suburbs.

It's like a zombie glacier --

Slow, but unstoppable.

Narrator: and something Transforms the sahara desert

Into a technicolor wonderland.

I've never seen anything Like this.

Baffling phenomena, Mysteries from space.

What on earth are they?

-- captions by vitac -- Www.Vitac.Com

Captions paid for by Discovery communications

Narrator: july 11, 2015,

Notorious drug lord "El chapo" guzmán

Vanishes from his cell

In mexico's Most heavily guarded prison.

The altiplano prison Is a fortress

Designed to be escape-proof.

There's an army of guards With military-grade weaponry

And state-of-the-art technology.

Narrator: The high profile escape poses

Difficult questions For the authorities.

Nobody saw that?

Nobody heard anything?

That's crazy.

How do you go about that Without drawing attention?

That shouldn't be possible.

Narrator: one satellite image Could hold the answers.

El chapo's escape was actually

A rather remarkable Engineering feat,

Which we can see In that image.

And it -- it's an amazing Piece of work

If you think about it.

Narrator: altiplano prison is In central mexico,

50 miles from mexico city.

It's supposed to be One of the most

Secure incarceration Facilities on the planet.

Many of the security features Are visible from space.

You look at the satellite Images of the prison today,

It's nothing but empty space All around.

And that's by design 'cause you want clear sight

To be able to see the bad guys Coming in or out.

Narrator: along with the walls And towers,

A battery of cameras covers Every approach to the prison.

It even has state-of-the-art Seismic sensors

To detect ground tremors Caused by tunneling.

It's the only prison in mexico Believed secure enough

To hold the legendary criminal.

El chapo was a bad, bad dude.

He's implicated In all sorts of things.

Murders, massacres,

Kidnappings, extortions, You name it.

Enormously ruthless individual.

Um, a lot of blood On this man's hands.

He's made billions, Actually, $3 billion a year,

In drug trafficking, contraband.

He controls Government officials.

He's almost untouchable.

Narrator: el chapo guzmán Has escaped custody once before.

So when he was caught In february 2014,

The authorities made sure He was locked up

In what they thought Was an unbreakable prison.

But despite all The security measures,

In july 2015,

El chapo disappears Without trace.

It's like something about of A marvel comic book, you know?

Narrator: a satellite photograph Taken just before

The escape initially seems To offer no clue to the mystery.

But when analysts compare it To one taken a year before,

They notice a key difference.

We can clearly see that There's been some very focused

And targeted construction.

Narrator: at some point in The 12 months before he escaped,

A farmhouse has appeared Less than a mile

From the altiplano prison.

February 2014, it's not there. It's an empty field.

February 2015, There's your farmhouse.

The questions that This image raises

Is actually what is The building there to do?

It's set back From the main road.

And that would really suggest That, uh, somebody

Doesn't want people To go to that area.

You have the world's Most wanted man in a prison,

I would think that Mexican intelligence

And law enforcement

Would be overseeing That whole area.

Surprising that they Didn't see that.

Narrator: when police finally Investigate the farmhouse,

They make A mind-blowing discovery --

A newly dug tunnel Almost a mile long.

Members of el chapo's Drugs cartel

Had dug a tunnel Into the prison,

Evading all of Its high-tech security.

Turned out the tunnel Had a very precise

Predetermined course,

Turning a couple of times

To avoid the prison's Seismic sensors.

Narrator: digging a secret Tunnel almost a mile in length

To arrive at a 3-foot square Shower drain

Requires extraordinary planning And precision.

El chapo's escape shows A real high degree

Of skill In terms of the engineers

That were responsible For digging this tunnel.

Narrator: el chapo's people Had thought of everything.

Had electricity, Had a lighting system in there.

Had transportation, Had oxygen supplies.

When the guards go into The escape tunnel

And follow it All the way to the end,

They find a motorcycle.

Evidently, el chapo Didn't want to walk.

Narrator: throughout the whole Elaborate escape bit,

The tunnelers leave clues All hidden in plain sight.

If you go back into The satellite images,

You can actually See the progression

Of this construction site And the tunnel.

It took 12 to 16 months To construct.

Narrator: satellite imagery Could have prevented the escape

Of one of the most dangerous Criminals on the planet.

Chapo's tunnel will Forever live in infamy

On a satellite image.

But nobody in the prison,

None of the officials,

Not a guy driving a truck,

Not the guy delivering the food,

Nobody saw it.

Narrator: el chapo guzmán's Freedom doesn't last long.

Mexican law enforcement Track down his location

When he uses a cellphone To exchange messages

With mexican soap opera actress Kate del castillo.

It appears that, uh, guzmán, uh,

For all his brutality, uh,

And all his reputation, Had a schoolboy crush on her.

That communication between The two of them

Allowed us to lock in on Where he was.

Narrator: in january 2016,

Mexican federal police And special forces

Recapture el chapo After a fierce gun fight.

He's returned to The altiplano prison

To serve the rest Of his sentence.

The federal penitentiary Has now undergone renovations

To improve security.

Whether they're enough To hold el chapo

Remains to be seen.

An aerial image taken Over the southern

Sahara desert reveals Dazzling pockets of color

Standing out From the rocky terrain.

Well, this is A-a really strange image.

There looks to be kind Of a honeycomb kind of texture.

It almost looks like Soap bubbles on the land.

It's, uh, very puzzling What this might be.

I've never seen Anything like this.

Narrator: june 21, 2003,

A photographer Flying over the southern sahara

Captures a bizarre image.

Hundreds of brightly-colored Circles standing out

From the barren landscape.

These markings, uh, Are really intriguing.

What could create such a bizarre And beautiful landscape?

Looking closer, They look like ponds.

But...For what?

Narrator: the image is taken Over teguidda-n-tessoumt

In niger, west africa.

Investigators first consider Whether the area's geology

Could be responsible For the colors.

This location sits In a dramatic landscape,

Formed by millennia Of violent volcanic eruptions.

There are some volcanoes In this part of africa.

And so the question is, You know,

Could this be caused By those volcanoes?

Narrator: intense underground Volcanic heat

Can create bright-colored Hot pools of water.

The pools remind me, uh,

A bit of hot springs In geothermal areas

Where the volcanoes Are heating up the ground,

Hot water, uh, is rising up.

There's big bubbles Creating these circular pits,

Or depressions in the ground.

The color, the nature,

All of these things Resemble hot springs.

In yellowstone, there are Beautiful hot springs

That are green and blue And sometimes even orange.

Typically, it's associated With algae growing in them.

Narrator: if the mysterious Colored ponds in the image

Are volcanic like The yellowstone springs,

It could be bad news For the people of niger.

Yellowstone's Hot springs are powered

By the world's big supervolcano,

Bubbling underground.

Niger's colored ponds could be

A warning sign Of a volcanic apocalypse

Brewing beneath the sands.

If it were volcanic, It may mean that

There's a more active system Coming up beneath.

There could be volcanic Eruptions again in the future.

Narrator: But the aerial image is missing

A crucial piece of evidence.

We would expect these would Have steam coming out of them

If they were hot springs.

Narrator: the absence of steam Above the pools

Means it's unlikely

That volcanic geothermal Activity created them.

If these colorful pools Aren't associated

With geothermal activity,

Then what are they?

If you look really closely,

You can see the shadow Of people near the pots.

But you can't see What they're doing.

Narrator: the vivid colors Make some suspect

That the pools Could be something to do

With west africa's famous Leather industry.

You can sometimes See pools of colored water

Like this in tanneries

Where animal hides Are being turned to leather.

Narrator: Tanning leather is one of

The nastiest jobs on the planet.

Hides are first soaked For three days in cow urine

And pigeon poo To make them soft.

To create colored leather,

They are then dyed In pools of vivid pigments.

But there's a problem With the desert tannery theory.

You'd expect to see the leather Skins hanging out to dry.

But here, we only see The colored pools.

Narrator: tanning doesn't seem To be the answer.

But to geologists, the colors In the pools provide a clue

To what is going on.

I recognize some Of the same colors from colors

I've seen in the large Salt evaporation ponds

On the shores Of the great salt lake.

What we're looking at are Pits made by people

That are used to evaporate water To collect salt.

As the water evaporates,

The color of the residue changes From blue water

When they're full-up, To brown sludgy water

When they're half-full, To salt color,

Nearly white When it's all evaporated.

Narrator: For the people who live here,

The salt is far more Than just a seasoning for food.

Because it's portable And non-perishable,

They use it as money.

In this part of africa, salt is Used as a currency even today.

And the local nomads Have been trading salt

For as far back as we've known.

Narrator: salt caravans travel For up to three weeks,

Hundreds of miles Across the sahara,

To reach the source Of this precious commodity.

In ancient times,

These caravans could be up To 20,000 camels strong.

Because salt is -- Is essential for life,

The pits are a very Highly-prized possession.

Narrator: this remarkable image Has captured

The unique spectacle Of the people of niger

Harvesting wealth directly From the earth itself.

The salt is literally a lifeline

For the people that live there.

Narrator: a satellite passing Over a dangerous area of iraq

Captures An unidentified dark mark

In the blistering Desert terrain.

Why is it so dark?

What the heck is going on? It looks completely scorched.

Something's happened.

Narrator: december 2010, The worldview-2 satellite

Passes high over war-torn iraq.

It captures An unsettling image --

A dark mark seemingly Burnt into the earth.

The image was taken Near the city of nasiriyah,

200 miles southeast of baghdad.

This is a dangerous Part of the world.

Border conflicts, Guerrilla warfare,

Insurgencies have been Raging for decades.

Now you've got isis coming in.

There's just not been Any stability in the region

For a very long time.

Narrator: analysts immediately Wonder if the dark mark

In the image could be damage From one of iraq's many battles.

[ explosion ]

Something's happened. Bomb damage would come to mind.

This image does have Characteristics of a bomb site,

Sorta the scorched pattern That exists there.

So this image appears To be where a bomb

Or some kind of explosion Has taken place.

Narrator: The photograph was taken

Near the iraqi air defense Base of tallil,

A key strategic target

For american-led Coalition forces

During the first gulf war.

In the '90s, there was a battle

That took place not far from

Where this photograph was taken At the tallil air field.

Given that it housed A radar center,

It was, you know, right at Our targeting priorities.

Obviously, you take out The radar capabilities

Of the country to allow For a successful air campaign.

Narrator: But the scale of the dark mark

Doesn't seem big enough To be the result

Of sustained air strikes.

Tallil took a lot of ordnance At that time.

Given that we dropped A significant amount of

Ordnance, uh, in this area,

I'm surprised There's not more evidence

Of bomb damage.

Narrator: this may not be damage From air strikes.

But it could still be A grim legacy of the war

That devastated this country.

So the worst case scenario In my mind

Is that this image Is reflective of a burn,

What would be seen As a large-scale

Charring of the earth.

Enormous number of sites Share similar characteristics

To this image In terms of scorched earth.

You know, it's very sad.

Narrator: Scorched earth is the name given

To the destructive strategy Used by saddam hussein

At the end Of the first gulf war.

Over 700 oil wells

In kuwait were set ablaze By retreating iraqi troops,

Causing one of The largest man-made

Environmental disasters In history.

The policy of Defensive destruction

May have even extended To other sites suspected

Of holding weapons Of mass destruction.

There were places like this All over the country,

Sites that had been Suspected for chemical

And biological warfare

That were completely burned down

And blown up For no apparent reason.

You should be very concerned

When you see scorched Earth marks, you know.

What the heck is going on?

What is it that They're blowing up?

What is it, you know, that We should be looking at here?

Narrator: further Investigation casts doubt

On the scorched earth theory.

The site in the satellite image Is 100 miles

From the oil fields Destroyed in 1991.

And the nearby tallil air base Was occupied by u.S. Forces

In the second gulf war.

Investigators are forced to look Much further back in history

To try to solve the mystery Of the dark mark.

This is a area where The archaeological record

Is dense and, uh, the history's Incredibly rich.

Narrator: Excavating sites in a country

As dangerous as iraq

Is virtually impossible For archaeologists.

Hanson: modern excavations have Been limited by conflict,

Uh, in iraq for some time.

Something like only 5% Of the country

Has really been Thoroughly analyzed

For archaeological sites.

Narrator: In these danger zones,

Archaeologists must rely

On satellite photographs To study sites.

Features visible in The satellite image

Suggest the dark mark

Could be some kind Of ancient settlement.

When you zoom into the site, You can see that it's elevated.

Narrator: It's possible the raised area

Was created by centuries Of human occupation,

Building and rebuilding,

With layers of ruins Creating an artificial mound.

And so you're going To see these classic marks

Of being elevated,

Being circular, Um, and being darker

Than the surrounding flat plain, Which is a clear indication

That it's An archaeological site.

Iraq, of course, Is known to us, uh, perhaps,

All for the wrong reasons.

Iraq, in the ancient world,

Was one of the most Important regions, uh,

For many Ancient cities, uh,

Human societies, For instance, babylon.

Narrator: this image was taken Near to the remains

Of a great babylonian City called ur,

One of the first cities Built by mankind.

Altaweel: Ur was, at one point, one of

The most important cities In the ancient world.

It was a very Rich-trading town.

It connected to faraway places Such as india, as in egypt.

Uh, it brought all this Wealth together,

Uh, to create, uh, Fantastic structures.

So it was a place Of great fascination,

A place of great wonder.

Narrator: The ancient city of ur

Is one of the birthplaces Of civilization.

This area is where Humanity first

Unlocked the mystery of writing.

Here was one of The first city-states

With the earliest forms Of government.

And just 12 miles from ur Is the site in the image,

Known locally as teilhaber.

Teilhaber was discovered Using satellite imagery.

It, perhaps, was a kind Of satellite town or suburb,

If you will, of ancient ur.

Narrator: the site in the image Was deemed too dangerous

To visit until 2012,

When archaeologists finally got The green light to excavate it.

Uh, radio carbon dates Were used to date

When the site was occupied.

Roughly around 1800 b.C.,

So that's roughly 4,000 years old.

Most recent excavations at this Site have found tablets,

Ancient cuneiform tablets.

And this is really Suggestive of the fact

That it was Facilitating administration

For probably the city of ur

And then also The province of ur.

[ gunshot ]

Narrator: The continuing conflict

Gripping iraq prevents

Fuller exploration of sites Like teilhaber.

Many of its secrets May still lie buried.

But without satellite imagery,

They could have Been lost forever.

We're looking at the dawn Of civilization.

There's much more to discover.

And the more we discover, The more we learn about

How that society Has actually affected us

In terms of its influence And impact on the world.

Narrator: an astronaut looking Down over europe

From the international Space station

Takes an extraordinary Photograph --

A vast expanse Of shining white light.

We're looking at The southern coast of spain.

And you see the desert up Here and the ocean down here.

And then, in between, Is this massive white surface.

And you wonder, "Where has the desert gone?"

Narrator: february 7, 2004,

As the international Space station

Orbits high above Southern spain,

An astronaut takes An extraordinary photograph.

A glowing white mass Seems to be spreading

Across an area of desert.

Is that natural or man-made?

Narrator: the remarkable image Was taken over almeria,

Southern spain, The dryest region in europe.

The area that we're Looking at here is the area

That they used to make The old clint eastwood

Spaghetti western Movies of the '60s.

Those movies had Stark brown landscapes.

One wonders, "What has changed Between the time

"Of those movies And the stark whiteness

That we see In the images today?"

Narrator: is it possible that Freak weather conditions

Could explain This strange white-out?

This might be a picture Of a rare snowfall.

Snowstorms can be very heavy Near mountain areas.

You get that lift and elevation.

And that helps To generate cloud development.

And that could fall with Some heavy snow in that area.

Narrator: A snowstorm in a desert isn't

As weird as it might sound.

In 2015, killer storm goliath

Caused 10-foot snowdrifts In the deserts of texas

And new mexico.

But analysis of weather data

From the time Of the image records

Light winds with Moderate temperatures.

There was no snowstorm.

Meteorologists struggle To find a new theory.

I'm left confused.

What could cause such An intricate white shape

In what is obviously A fairly limited coastal area?

If these astronauts Aboard the iss

Aren't seeing a blanket Of snow across almeria,

Then what exactly is it That they're looking at?

Narrator: some of the brightest White landscapes visible

From space are salt flats.

From the space station, I have seen salt flats both

In utah and in bolivia.

And they're big, Large expanses of pretty,

You know, white material.

Salt flats are areas

That used to have Salt water on top.

But then the salt water Has evaporated away,

Leaving this dry, Crusty white salt.

And sometimes, These can be large enough

That they're seen from space.

Narrator: This area of spain does have

A salt-mining industry.

Around 40,000 tons of salt

Are harvested each year From a site called cabo de gata.

But this is located 20 miles away,

Across the gulf of almeria.

Something else must be going on.

Another detail in the image Poses further questions.

Instead of a solid white surface

That would be typical Of a salt flat,

Hundreds of dark lines

Divide the glowing white mass Into distinct chunks.

Why is it broken up And interspersed

With little bits Of land and water,

Almost as if they're Little squares or pieces

That have been thrown down?

Narrator: In some parts of the world,

Farmers divide their land

Into small intensely Irrigated pools

That can sparkle in the sun.

The enormous honghe hani Rice terraces in china

Are an example of this.

They cover an area roughly The size of washington, d.C.,

Big enough to be Seen from space.

The chinese rice terraces Can be much larger than --

Than many people think.

They can be up to 3,000 steps Down, which is quite enormous.

It means they can be seen From a long way up.

Vast areas of china grow rice.

And they do grow rice in spain.

Is that what this is?

Rice is really important In spain.

It forms the base of their Most famous dish, paella.

And they actually grow quite A bit of rice in the country.

Narrator: analysis of historical Satellite images

Shows that almeria began Turning white in the 1970s.

That's simply not enough time

To have developed Paddy fields large enough

To be visible from space.

It can take generations To transform an area

This large into paddy fields.

This change has Happened too quickly.

Rice is not the answer.

Narrator: Aerial drone footage ultimately

Reveals the true nature Of the glowing white mass.

Practically the whole region Is covered in white plastic.

What looks like snow, Salt, or rice

Is actually 150,000 square miles

Of super reflective greenhouses And polytunnels.

Narrator: this is the biggest Concentration

Of greenhouses in the world.

It is larger an area

Than the city Of denver, colorado.

Narrator: farmers grow 2.5 million tons of fruit

And vegetables here every year,

Most of which is exported To the rest of europe.

Thanks to the greenhouses,

Food can be grown All year round.

But almeria's plastic sea Doesn't just help produce

An extraordinary amount of food.

The greenhouses seem to alter The temperature

Of the outside air For miles around.

One of the intriguing things

About all of these greenhouses

Is that it's bouncing back A lot of sunlight into space.

In contrast to the world

Where the temperature Has been going up,

For this localized region,

It's actually been going down.

Over the last 25 years,

The temperature of this region

Has gone down by over a degree.

Narrator: by reflecting sunlight Back into space,

The plastic sea has lowered Almeria's average temperature.

The vast expanse Of white plastic

Is turning back time.

This strange anomaly Could now offer

A possible solution For a global problem.

It tells us that The concept of certain

Kinds of geoengineering Can actually work.

Narrator: the food from almeria Feeds much of europe.

The beneficial effects Of the plastic sea

Could extend much further.

Reflecting sunlight might offer

The first real hope Of slowing climate change.

Narrator: An aerial photograph taken

By a government survey team In australia

Reveals a weird pockmarked Pattern scarring the outback.

You can see This very obvious gap here.

This is fairly typical-sized.

You could park a car in it.

What could make the grass Grow in round rings?

Narrator: august 2013,

An aerial photograph taken

By an australian Government survey team

Reveals something unusual in A remote patch of the outback --

A huge pattern Of bright red pockmarks

Scarring the landscape For hundreds of square miles.

I get kinda creeped out

When I see images Of pustules and stuff.

And that's kind of what It looks like right here.

Just really a bad case Of acne or something.

Narrator: the photograph is Taken near the remote

Town of newman in the pilbara,

A sparsely populated Desert region

Of western australia.

So you got a lotta green, And then all these, like,

Very evenly-spaced brown spots.

They're just so evenly spaced.

That's the thing That's really remarkable.

So what's really going on here?

Narrator: the outback makes up Around 70% of australia's

2.9 million Square mile land mass.

But these red pockmarks appear Only in the pilbara region.

This image is fascinating.

It's something like I've never seen before.

Narrator: Another satellite image,

Taken over 6,000 miles Away in africa,

Could offer a clue To what's happening.

The only other place In the world

That something like this Has been found is in namibia.

[ chanting ]

Narrator: the people that Inhabit this wilderness

Are an isolated tribe Called the himba.

They believe the circles Seen in the namibian desert

Are scorch marks left

By the breath Of a legendary dragon.

There are obviously No dragons burning the earth.

But the deserts of Australia and namibia

Have both been scorched By apocalyptic fires.

Could the marks in Both satellite images

Be explained By nuclear testing?

There is a history Of testing nuclear weapons

In very desolate desert areas.

You do nuke test in a desert Area for two reasons.

You have no people To worry about.

And then the second thing is,

You don't have A lotta water or rain

To carry radiation around.

So it's -- it's pretty Self-contained

In the desert area.

Narrator: Declassified military documents

Reveal that, in the 1950s,

The british conducted Top-secret nuclear experiments

In the australian outback.

The combined force Of the test weapons was

Twice that of that of the bomb Dropped on hiroshima in 1945.

Namibia also had Nuclear testing.

So you've gotta ask, could this Be the common denominator?

Narrator: Radioactive fall-out has been

Known to kill vegetation.

But the only aboveground Nuclear tests

Ever to happen In australia took place

At least 300 miles From the location in the image.

And the terrain doesn't Show the telltale signs

Of an underground Nuclear explosion.

Looking at that image, there's No indication of subsidence

That you'd get With an underground test.

Uh, there's no, uh,

Indication of a lotta people Moving back

And forth across the area If it was a nuclear test.

Narrator: the mystery attracts The attention

Of environmental scientist Bronwyn bell.

So I was on the plane Coming into land

And I noticed out the window

That there was a pattern In the spinifex.

Narrator: bell is the first Scientist to investigate

The australian phenomenon On the ground.

You can see you've got all The individual spinifex plants

Around the outside,

Um, but then this gap In the middle.

Narrator: This tough spiky grass

Is inedible to most animals And insects,

Except one -- the termite.

Is it possible that these tiny

Insects are harvesting The spinifex grass,

Leaving circles Of bare earth behind?

So you can see here, We've got some termite mounds.

And so the theory is that That termite activity

Is actually what's causing These circles to occur.

But you don't get these Termite mounds occurring

Consistently Throughout the area.

And you'll have lots of circles Which will have none of that

Sort of activity in it at all.

Narrator: bell turns to another Scientist for help.

Biologist dr. Stephan getzin

Studied the same Weird phenomenon in namibia.

He calls the strange patches Fairy circles.

When I saw these picture For the first time,

I was really blown away.

What was weird, uh, was the fact

That this image is From australia and --

And not from southern africa.

And until now,

People believed That fairy circles

To only exist in namibia.

Narrator: getzin's findings Back up bell's belief

That termites Are not responsible.

We took a hammer and crushed

The soil crust And looked underneath.

There was no termite, Uh, galleries, nothing.

Termites could never explain These large areas

With bare soil where Nothing's growing.

Narrator: Getzin thinks that something

Much more mind-boggling Is going on.

He believes that the plants Are organizing themselves.

And you see that the plants

Are arranging themselves By self-organization

To maximize water access

And to grow better.

Narrator: getzin has a theory That the plants

Have evolved to grow in circles

As an adaptation to survive

In such a dry desert.

In arid environments When water is not enough

To sustain

The complete coverage With vegetation,

Plants create patterns.

And these plants Are simply forming a circle

In order to maximize Access to water.

The soil in the center Of these circles

Actually helps conduct moisture

Out to the plants On the outside.

Narrator: As if some higher intelligence

Is directing them,

The plants arrange themselves

To form large Circular catchment areas.

These act as rain collectors,

Which then direct any water Back towards the plants.

The smart plant theory Is still unproven.

But it could offer an answer

To the mysterious circles Seen in two deserts

More than 6,000 miles apart.

Fairy circles here In the pilbara

Are just another example Of how, you know,

Nature responds To the climate it's got.

Plants are smarter Than you think.

Narrator: an aerial image of

A bizarre icy weather phenomenon Baffles meteorologists.

There's a ramp of ice Or snow or something

Between the water, uh, And the houses.

But behind that, The surface of the water

Looks pretty ice-free.

Narrator: a gigantic ice wall Has appeared from nowhere.

The image doesn't show any snow In the surrounding areas.

Why would you have That much ice

Just very isolated Right along the coastline?

We gotta figure out What's goin' on here.

Narrator: May 2013, an aerial image

Is captured of a wall of ice

Invading the residential shores

Of a normally tranquil lake In canada.

Something weird has gone on.

Why would you have That much ice

Just very isolated Right along the coastline?

Narrator: the image comes from Dauphin lake

In western manitoba.

This area of canada Can suffer heavy snowfall,

Even during springtime.

Is it possible that the wall Of ice was created

By a supersized blizzard?

Tremendous winds can carry snow

To the point of burying Entire buildings.

Snowdrifts are gonna happen

When you have a big snowstorm That comes into an area

And the snow gets blocked By an object.

Snow hits upon that, falls,

Stops and then starts To build up an accumulate.

Narrator: But the concentration of snow

And ice into one small area

Makes it clear this Is no ordinary blizzard.

I have seen my share Of snowdrifts.

But in this particular case,

The problem is that Where we see snowdrifts

Right along the coastline,

We don't see them Further inland.

And that's where we should Also see snowdrifts.

So the idea of just having A big blizzard go through,

Probably not the case here.

If it's not from a blizzard, What else could it be?

Narrator: investigators Face the disturbing possibility

That the wall could be caused By a strange natural force known

As lake-effect snow.

Lake-effect snow happens When you have warm air

Traveling across a lake.

Narrator: the air picks up Moisture as it travels

Until it hits The freezing cold ground

On the other side of the lake.

When you cool that air That's holding moisture down

To freezing,

All of a sudden, As it moves over land,

It dumps out lots And lots of snow.

A lake-effect snow Band can be so intense

That you can go From very good visibility

To absolutely zero

In the blink Of an eye with thunder

And lightning in the snow.

It's one of the most powerful Winter storm events possible.

Narrator: in many respects, Lake-effect snow

Could explain This strange phenomenon.

But it doesn't quite fit With the localized nature

Of the wall of ice.

One characteristic Of lake-effect snow

Is you get these long bands Of snow going inland,

Perpendicular to the lakeshore.

And that's not What's happening here.

So if it's not a snowdrift

And it's not lake-effect snow,

What is actually Causing all this ice

To build up right along This coastline?

Narrator: The search for the cause

Of the ice wall narrows down To the lake itself.

You can see from the image That there's probably

Substantial property Damage here.

What's going on here Is something referred to

As an ice shove,

Where wind has driven lake ice

Or sea ice, uh, up onto shore.

The ice in the front That moved onshore first

Had nowhere to go because ice Kept pushing from behind,

Much like a cattle stampede.

Narrator: Ice shoves can be devastating.

The relentless white wall grinds Over everything in its path.

And this strange phenomenon

Doesn't just hit The residents of dauphin lake.

Just one day later,

An unstoppable wave Of wind-shoved ice

Hits the lakeside community Of mille lacs, minnesota.

woman: look at that!

it's really pushin' in.

Narrator: Locals living on the lake edge

Caught the relentless Ice tide on camera.

It's like a zombie glacier --

Slow, but unstoppable.

Narrator: Footage of this ice shove

Became one of the most Widely shared videos of 2013,

With almost four million views.

how is it doing this?

The footage shows The ice creeping forward.

And it looks unstoppable.

nicky, it just busted through a door over here!

all the way through! the door's caving!

Narrator: Lakeside residents are powerless

To halt the destructive Phenomenon.

Ice at the front slows down.

And the ice Behind crashes into it.

But it keeps pushing it Forward, more and more.

And all of that massive ice

Ends up turning into This unstoppable steamroller.

It can create a massive Amount of destruction.

The homeowners had no idea What was goin' on.

It was this mystery Force of nature

Coming at them from the lake.

And that moment just happened To be caught on video.

Narrator: residents of Dauphin lake in canada

And mille lacs in minnesota

Can only hope the rare Weather conditions

That produced the ice Shove never occur again.