Original subtitles

[narrator] How could the weather in space

have impacted the fate of the titanic?

A strong geomagnetic storm can cause havoc on a large scale.

[narrator] What secrets of America's nuclear past

lie in the frozen waters of Greenland?

The fact that people haven't realized what it was...

is mind-blowing.

[narrator] And who is to blame when a bag of human hands

is found on the banks of a Siberian river?

Who are these people? Whose hands are they?

[Jeremy] The underwater realm is another dimension.

It's a physically hostile place

where dreams of promise can sink into darkness.

I'm Jeremy Wade, and I'm searching the world

to bring you the most iconic and baffling underwater mysteries

known to science.

The vast majority of our ocean is unobserved, unmapped, and unexplored.

[Jeremy] It's a dangerous frontier that swallows evidence...

You have nowhere to run.

[Jeremy]...where unknown is normal,

and understanding is rare.

It's a tale we all know.

April 14th, 1912.

RMS Titanic collides with an iceberg and sinks into

the freezing water of the North Atlantic.

More than 1,500 people perish.

The reasons behind the world's most infamous ocean disaster

have been debated for more than a century,

from lack of lifeboats to human error.

Now, could a phenomenon called space weather

change everything we thought we knew

about the loss of this unsinkable ship?

The largest moving man-made structure on Earth

set sail from Southampton, heading to New York on its maiden voyage.

Over 2,000 passengers and crew are on board the Titanic.

It was the largest and most luxurious ship that had been built.

It was supposed to be the most secure,

the safest, the most watertight.

[Michael] Everybody knows the story of the Titanic.

The greatest ship, the ship that wasn't made to sink actually sank.

[Jeremy] Four days into her journey,

the Titanic collides with an immense iceberg.

The frozen mass towers 100 feet above the water,

and weighs an immovable two million tons.

Only 705 people survive, less than a third of those on board.

[Beverly] How did this happen?

How come no one came to the rescue right away?

Who's to blame?

We're still searching for answers more than 100 years later.

[Jeremy] An inquiry begins into what went so tragically wrong.

The month-long investigation is overseen by Lord Mersey

who takes volumes of notes in his private journals.

After the hearings end,

these journals are kept locked away by his descendants

for more than a century.

It's not until 2020 that they're finally released.

His journals reveal his innermost thoughts on the inquiry.

[Jeremy] Can Lord Mersey's newly-disclosed writings

finally expose the truth?

He mentions in the journal that the watertight doors in the hull

were left open after initially being closed.

If these doors are left open, then water can flood the length of the vessel

and also create instability as the weight shifts.

[Jeremy] This finding was made public in the initial investigation.

But the notes also confirm something that's only ever been speculated.

Mersey had underlined and paid special attention to one key detail.

There was no reduction in speed following the impact.

Captain Smith ordered the ship to move forward at a steady pace

for another 20 minutes,

a decision that had disastrous consequences.

By keeping going, that means more water coming into the hull.

This puts pressure on the bulkheads.

[Jeremy] The journals give us new insight into how the ship sank so quickly.

But the full story of how the collision happened is still a mystery.

Then, a scientific discovery in 2020

gives rise to a completely new theory,

something that has never been considered before.

The night that it sank, it was actually a very beautiful, very cold but very calm night.

The sea was said to have been really flat.

[Michael] Many of the people who were rescued said,

"Oh, the aurora borealis were beautiful that night."

They fanned through the sky. It was marvelous, it was spectacular.

[Jeremy] Behind this beautiful light show lies formidable power,

and it's something that weather researcher, Mila Zinkova,

believes could have played a defining role in the Titanic disaster.

[Jeremy] Geomagnetic or solar storms are caused by

charged particles shooting towards the Earth

at a speed of nearly 200,000 miles per second.

[Colin] The magnetic field guides these particles

towards the north and the south poles.

And so, when they come down to around 100 kilometers or so,

they bang into the molecules of the air

and they cause light to be emitted.

[Jeremy] And these charged particles in the sky

cause more than an extraordinary light show.

A strong geomagnetic storm can cause havoc,

and I mean havoc on a large scale.

All this kind of cloud of particles

cause the magnetic field to kind of wobble or to vibrate.

And that generates currents in the Earth.

If you look at the global risks to civilization,

space weather is right up there.

[Jeremy] So, extreme weather conditions in space can wreak havoc on Earth.

1989, a geomagnetic storm

causes a 12-hour power outage in Quebec.

It damages a nuclear power plant in New Jersey,

plunging six million people into darkness.

That solar storm of 1989 was an immensely powerful storm.

Big. Bigger than your average solar storm.

[Jeremy] Could a similar event have contributed

to the sinking of the world's greatest ship?

In the Titanic era,

a compass was the most important navigational tool.

an instrument that depends totally on the stability of the Earth's magnetic field.

If you were sitting on a ship in the middle of the ocean,

a wobble to the magnetic field could make it look like north was somewhere else.

[Jeremy] Could the geomagnetic storm that night

have affected the ship's compass so much

that it changed the Titanic's intended course?

[Jeremy] By studying the space weather from that night,

Mila made a vital breakthrough.

[Jeremy] Most major solar storms occur

between 50 and 55 degrees of geomagnetic latitude,

the precise region where the Titanic is found.

Something else has also been recently discovered,

a hand-drawn observation of the Sun from the day before the Titanic sinks

showing a sun spot.

Sun spots are areas on the Sun where the magnetic field is much stronger.

This can cause solar flares and explosions called coronal mass ejections.

These can contribute to even more powerful geomagnetic storms on Earth.

[Jeremy] Is this further evidence that an intense solar storm

played a decisive role in the tragedy?

Aurora borealis happens all the time.

Were there people in the Canadian Maritimes going,

"Whoo, this is a light show"?

Were there people on the American West Coast, Alaska, and Norway

seeing the same thing?

[Jeremy] Mila's research uncovers that magnetometers around the world

did, in fact, pick up the storm.

Sensors in Alaska, Canada, and Scotland

all are disturbed around the time of the sinking.

So, this celestial event was strong enough to be detected everywhere.

But did it have a critical influence

on the reliability of the Titanic's compass?

[Mila speaking]

[Jeremy] Mila believes that if the compass was just 0.5 degrees off,

it could've altered the Titanic's course,

and therefore, how it collided with the iceberg.

[Beverly] The ship hits the iceberg on the side,

and six of the 16 compartments are damaged.

If three of the watertight compartments had been damaged,

it might have survived.

A solar storm may have contributed

to the catastrophic sinking of the Titanic.

But further investigation is showing that its effects

may not have been entirely destructive.

It could even have played a key beneficial role

in the rescue of the survivors.

More than 2,000 passengers and crew

fought for their lives on the night the Titanic sank.

Over 700 of them managed to escape the icy deaths of the North Atlantic.

Many people are still wondering how they did it.

New research suggests space weather played a key role

in the rescue ship, Carpathia, finding the survivors.

Was this a celestial savior to those in need of rescue?

23:40 hours, April 14th, 1912.

The Titanic has collided with an iceberg of unimaginable size.

The ship's fourth officer, Joseph Boxhall

determines their position to send out an SOS.

[Beverly] Boxhall calculates a SOS position

and he's 13 nautical miles off.

[Jeremy] If the geomagnetic storm did affect the Titanic's compass,

it could have contributed to this false reading,

with big ramifications for the rescue.

The Titanic's incorrect position is sent out.

Yet, bizarrely, one ship, the RMS Carpathia,

manages to locate the stricken lifeboats.

How could this be possible if they received the wrong location?

[Jeremy] As well as the Titanic's compass,

Mila believes the storm also affected the Carpathia,

accidentally leading them straight to the lifeboats.

[Jeremy] If the Carpathia had not been affected by the compass variation,

it could've missed the lifeboats by six nautical miles.

Because of this, the Carpathia saves

705 people from the freezing water.

But could the storm have had a further impact

on why more boats didn't come to the Titanic's aid?

The storm that night might have affected

the radio communication of nearby ships,

with cataclysmic effect.

[Jeremy] Many ships that night

record abnormal malfunctions

of their communication equipment.

[Simon] La Provence couldn't contact the Titanic

but could hear the Olympic

which was 500 miles further away than the Titanic.

[Beverly] Baltic couldn't hear the Mount Temple,

but it could communicate

with the Virginia which was further away.

[Michael] The Mount Temple responds to the SOS,

but the Titanic doesn't get the call.

[Jeremy] What dealt the definitive blow to the Titanic

with its 2200 people on board will continue to confound us.

But the might of space weather

has added a new line of enquiry to this tragic mystery.

It was just another strike for it.

I guess once you say you have an unsinkable ship,

the universe is gonna turn against you

and try to sink ya at whatever the cost.

Every year eight million tons

of trash ends up in our oceans.

In 2018 on a remote Siberian island

something turns up that is truly bizarre,

a bag of frozen hands.

Where it came from and how it ended up on this icy beach

puzzles locals and scientists alike.

The Amur river in the South-East of Siberia,

19 miles from the border with China.

On March 8th, 2018,

a fisherman makes a grim discovery.

He sees a hand coming out of the snow...

[Jeremy] He searches for clues as to where it has come from

and makes an even more disturbing find.

When he goes to investigate it further,

he finds 53 more hands.

[Jeremy] The severed, frozen hands are spilling out

of an unmarked bag.

It is not a good day if you stumbled upon a bag full of frozen hands.

[Jeremy] This gory find sparks intense speculation.

Why would somebody have a bag of frozen hands?

Who are these people? Whose hands are they?

[Jeremy] Incredibly, body parts washing up on shores around the world

is not a new phenomenon.

There were cases of feet showing up

on the coastline in Canada...

15 feet have been found over 12 years.

[Jeremy] Investigations reveal the feet have become severed

from the decomposing bodies

of accidental deaths or suicides,

kept intact by the sneakers

that acted as floatation devices.

Unique ocean currents in this wild and remote area

push them all onto a small strip of shore

in British Columbia.

Can the same science help pin-point where

the gruesome bag of hands started its Siberian journey

and lead investigators to the people responsible?

[Beverly] Were they brought there?

Did they go through the water?

You could have a, sort of, going along the bottom in a slower manner

versus the speed at which it would probably travel

if it stayed on the surface.

[Jeremy] How the bag travelled

would also depend on the Siberian climate.

[Rob] The water around the island where the bag was found,

wouldn't have been fully flowing until April.

So there could be ice jams which could raise the level of the river...

All of these little pieces of information and clues

can help to reconstruct their history.

[Jeremy] Whether the bag washed ashore

the previous spring and was then buried under snow

or just travelled a short distance more recently is unknown.

But this doesn't stop some people jumping to sinister conclusions.

Clearly they were collected and put together.

[Jeremy] As the story breaks wild rumors circulate.

[Peter] This location is 19 miles

from where the river borders with China.

Is this the work of Russian or Chinese mafia?

Could it be evidence

of limbs cut off to hide their identities?

When a bag of frozen hands

washes up from a Siberian river

there's intense speculation

that organized crime syndicates are involved.

They're infamous for disposing their victims

in the watery depths of rivers and oceans.

However, authorities discount the controversial theory

and announce that the hands

have come from a local forensics lab.

It's a claim that raises even more suspicion.

Russian investigators assert that the hands were severed

during routine autopsies

and kept for evidence.

Why would the hands even need to be retained?

[Lisa] In some cases when a dead body is discovered

and you're unable to identify it,

medical examiners will retain one of their hands

to hold on to the fingerprints.

This way they hope to be able

to identify them in the future.

Why wouldn't you just do the fingerprints

with the hands still attached to the body?

[Jeremy] Forensic labs elsewhere in the world

have been known to hold on to body parts.

London in 1989,

in a tragic accident the Marchioness, pleasure boat

collides with a dredger on the river Thames and sinks.

51 people are killed.

[Lisa] More than 20 hands of the victims

of the Marchioness are severed and retained.

These hands should have been returned to their rightful owners

and buried along with the rest of the human remains.

[Jeremy] The hands from the Marchioness disaster

and the 54 frozen hands found in Siberia

do have something in common.

They've all been immersed in water.

You can get expansion and changes to the skin

that's going to alter what the prints looked like.

So, to be able to fingerprint

a hand that's gone through that type of decomposition

is very difficult.

[Jeremy] At the time of the Marchioness disaster

fingerprinting is the main way to identify a dead body.

And the only lab that has the equipment

to take prints from water-logged hands

has limited storage.

However 30 years later

when the Siberian frozen hands are discovered,

forensic methods have moved on.

We don't need to sever hands any more to identify who someone is.

[Jeremy] Today DNA analysis and other tools

tell us so much more than fingerprints can.

Radiocarbon dating can be used

to determine when an individual lived and died.

Stable isotope analysis allows us to determine

the kinds of things that they ate.

While strontium isotope analysis

can tell us where they grew up.

[Jeremy] Why would the frozen hands be removed

when advances in forensic investigation

means it's no longer necessary?

Storing a body takes up a lot of space

and it's quite costly in a morgue or facility that has refrigeration.

So, instead storing a single hand is much easier

and cost effective.

[Jeremy] If they were retained for identification

why are they then found abandoned in a bag?

This is not the way they dispose of human remains

in any circumstance.

[Jeremy] A day after the discovery,

in a bizarre twist,

the official narrative is refuted.

Both the forensic authorities and the disposal company

strongly deny any involvement.

They claim their last disposal was made in 2015.

[Jeremy] Who severed the hands and why

may never be fully proven

but is there still a chance

of finding out who they belong to?

DNA is particularly well preserved

in very cold climates.

Some of the best preserved DNA we've ever discovered

has come from the Siberian region.

Even in the case of ice age animals.

So there's every chance that this DNA will lead us

to who these people are.

[Jeremy] What the genetic tests could reveal

and if they will even be undertaken is still unknown.

And there's still one big obstacle

to finally solving this puzzle.

If these people aren't on record

and nobody's actively looking for them this could remain a mystery.

In the early hours of Sunday, May 31st, 2020,

the megaton oil tanker, Willowy,

is sailing in the South Atlantic

when it puts out an urgent mayday call.

They've lost control

and they're spinning in circles.

Other ships in the area

are reported to be experiencing the same bizarre rotating.

What could be causing

this inexplicable nautical nightmare?

[Rob] The ship carrying thousands of tons of crude oil

starts spinning in a circle.

[siren blaring]

They lost control.

[Jeremy] Confusion erupts on the bridge as the captain

desperately tries to get back on course.

You would be in a huge state of panic...

It's devastation waiting to happen.

[Jeremy] What's even more frightening for the crew of the Willowy

is that four other ships

are reported to be sailing in circles nearby.

The potential for destruction is terrifying.

If they don't fix it,

they could well converge and crash.

[Jeremy] How is it possible for five gigantic vessels

to be turning in circles in the middle of the ocean?

To have so many ships at one time

having the same human errors seems quite odd.

Perhaps there's some sort of other physical force at play.

[Jeremy] 300 miles off the coast of South Africa

the crew of the oil tanker, Willowy,

are desperately searching for a reason

as to why they have suddenly started turning in circles,

dangerously close to four other ships.

[Alexander] At first the senior officers assumed

that it's sea currents.

That the oceans itself are moving the ships around.

[Jeremy] Could the answer behind this mystery

be down to the sheer power of the water?

[Lisa] Ocean currents may have contributed to its spinning a bit.

It's unlikely that ocean currents

could make a ship spin continuously.

[Jeremy] With the strength of the ocean currents

unlikely to be causing these bizarre nautical rotations,

what else might be behind this terrifying event?

[Lisa] The ocean is quite a lawless place.

[Jeremy] Could a new growing criminal activity

be responsible?

The more connected we are

to the internet and international systems,

the more likely we are to experience hacking.

Could someone have remotely hijacked the ship?

[Jeremy] Hackers can manipulate a vessel's navigational tools

by overriding its GPS signal.

[Alexander] You are feeding false data to the ship,

so it thinks it's doing a correct heading.

It's going in the right way.

So, if you can fool them,

then the ship will go where you want it to go.

[Jeremy] It's an illegal practice called spoofing.

But why would hackers

want to manipulate the Willowy's GPS?

[Rob] An oil tanker could potentially be the target of spoofing

to alter its course for some sort of nefarious purpose,

say for example, to run a vessel aground in a narrow straight.

[Jeremy] The 57,000 tons of crude oil on the Willowy

could be worth more than $11 million.

Are criminals trying to reroute it in an attempt to steal the valuable cargo?

Piracy has not gone away.

It's often connected with large, multinational criminal organizations.

Huge organizations which have

a lot of money, a lot of resources...

[Jeremy] In 2020, GPS data appears to show

more megaton cargo ships spinning out of control

with scientific investigator, SkyTruth,

revealing a strange case of Point Reyes, California.

The data shows many circles, which are supposed to be the paths of different ships.

[Jeremy] The team monitoring the Californian data believe these tracks are possibly

the result of large-scale, GPS manipulation

designed to undermine a tracking network

called Automatic Identification System, or AIS.

[Helen] It's a system that ships have to have now

to track where they are.

It means you can finally see who's doing what.

[Jeremy] Until AIS started monitoring criminal activity,

the sea was much harder to police.

[Rob] There is piracy, there's illegal contraband smuggling.

There is human trafficking, there's the trading in arms.

It's really a Wild West.

So, obviously, there is a huge interest by a lot of criminals

in subverting these systems.

[Jeremy] Extreme manipulation of the AIS system has also been investigated

along the Chinese coast in 2019,

when the GPS of hundreds of ships mysteriously malfunctioned.

All of them reportedly close to valuable targets for criminals.

This seems to often occur near oil ports and refinery facilities.

[Jeremy] Is this evidence that powerful entities are determined

to distort the GPS of ships in order to conceal criminal activity.

International states are engaging in hacking of all forms more and more.

So there's every chance that international superpowers

could be responsible for GPS spoofing.

[Jeremy] No one knows for sure who is behind the spoofing

of the Chinese and American coasts.

But is the Willowy a victim of GPS manipulation.

Where the oil tanker was sailing may give a tantalizing clue.

[Rob] There's less patrols, there's less scrutiny on that route.

So it would be much easier to hijack a vessel off the west coast of Africa

than it would off the coast of Europe, for example.

[Jeremy] After urgent investigation, the crew of the Willowy

in communication with officials on shore

come to a conclusion as to what is behind this bizarre behavior,

the ship's gyro compass.

It's one of the systems which the ship relies on

in order to maintain a steady course.

The gyro compass is wrong.

It's not calibrating.

[Jeremy] If it fails, it could cause exactly

the issues which the Willowy is experiencing,

potentially resulting in a crash with a nearby ship.

Luckily, they avoid a collision by switching

to their secondary gyro compass.

And for further measure, they then continue on their route

using an old-fashioned magnetic compass.

[Jeremy] But the failed gyro compass on the Willowy doesn't explain

why the four other ships are reportedly spinning.

Could a startling new discovery in the area they are sailing in

hold the key to unlocking this mystery?

The south Atlantic, where the Willowy and four other ships

are at risk from a looming menace,

one that's hidden from view, but growing by the day.

The planet and everyone on it is protected from the sun's deadly radiation

by the Earth's magnetic field.

But scientists have detected a localized weakening of this vital shield.

It's called the South Atlantic Anomaly.

The South Atlantic Anomaly is an anomaly over the South Atlantic,

but in space.

[Michael] The anomaly allows the sun's radiation

to penetrate deeper into the Earth's atmosphere.

[Jeremy] Between Chile and Zimbabwe, the earth's protective shield

has deteriorated six percent in just 50 years.

And the ships reported to be spinning are located directly below.

Could the extra radiation leaking into our atmosphere be affecting their navigation?

[Colin] Above the regions of the South Atlantic Anomaly,

we can have some problems with maybe detection

of the signals from the satellite, accuracy of the signals.

And that's because the medium between the ground

and the satellite has been affected.

[Michael] It's not out of the realm of possibility

that this could have affected the ships near the Willowy.

[Jeremy] And this growing dent in the Earth's magnetic field could be a sign

of something potentially catastrophic for the planet.

Collapse of the Earth's magnetic field would basically allow all the radiation

which is ejected from the sun to hit the surface of the Earth

without any form of defense.

Without it, we're doomed. It's that simple.

[sonar ping]

Deep below the surface of the Pacific Ocean,

a radioactive mystery is unfolding.

Throughout recent history, the testing of nuclear weapons by the world's superpowers

has been shrouded in secrecy.

But scientists are now discovering strange deep-sea creatures.

And hidden inside them, explosive secrets from the world's nuclear past.

2019, the scientists find in some of the deepest parts

of the Pacific Ocean something unusual.

These are huge.

The scientists observe that the amphipods that are living in deep water

are much larger than what you see in shallower water.

[Jeremy] And their freakish size is not the most bizarre discovery.

They are flooded with radiation.

[Jeremy] How can these creatures

dwelling in one of the most remote places on Earth be radioactive?

[explosion]

Between 1946 and 1958, the United States runs

numerous nuclear tests in the Marshall Islands in the Pacific.

[Jeremy] As the Cold War escalates and fears for American security intensify,

scientists test nuclear weapons for use against the Soviet Union

over and over in the south Pacific.

They fundamentally believe that the biggest possible bang

is the biggest possible deterrent.

[Jeremy] It should have taken centuries for our ocean currents

to carry this nuclear fallout to the deepest marine trenches.

But it turns out the radiation has spread much more quickly.

Radioactive carbon is now making its way into the marine food chain.

[Jeremy] Science has revealed that organisms at the sea's surface

have been ingesting this so-called bomb carbon since the 1950s.

And the organic matter from these surface organisms falls to the deepest sea beds,

where creatures like amphipods consume it.

[explosion]

[Jeremy] It's evidence that the Cold War nuclear fallout

could now be in every corner of our oceans.

But whether radioactive material is the reason

behind the amphipods' extraordinary size is contested.

Size difference could be for a few different reasons.

And it may not be affecting them in any way.

[Jeremy] In 1963, the nuclear testing

that created so-called radioactive amphipods comes to an end.

But 60 years later, on the other side of the world,

a discovery from deep under the arctic ice sheet

reveals another secret part of America's nuclear operations.

In 2019, at the University of Vermont,

climate scientist Drew Christ makes a life-changing discovery.

For me, as a climate scientist,

receiving these samples in the lab

was like holding the Holy Grail.

- [camera shutter clicks] - [Jeremy] It's the remains of an ice core

drilled from deep within Greenland's ice sheet.

An ice core is actually a tube of ice

which contains in it sediments and bits of rock.

[Jeremy] And this one has a very peculiar history.

What's so unusual about this particular ice core is that it bounced around

between various research institutes around the world over a number of years.

[Andrew] They were in these, like, scientific cookie jars

that had these old labels that were written that said,

"Camp Century's sub ice" on them.

[Jeremy] Camp Century is an American military

research base in northern Greenland.

But until recently, its operations have been veiled in secrecy.

What was its true purpose?

And what is the significance of the mysterious ice core

taken from deep beneath the camp?

The fact that this has been going around for nearly 40 years,

and people haven't realized what it was

is mind-blowing.

It's the height of the Cold War,

and the two great adversaries, America and Russia,

are separated by only two and a half miles at the narrowest point.

This threat leads the US Army to undertake one of its most secretive missions,

25 feet under the Greenland ice sheet.

What does this mysterious place deep below the frozen water

reveal about America's secret nuclear past,

and, surprisingly, the future of our planet?

The background to this story is very weird and kind of like science fiction.

[Jeremy] Imagine a network of 21 tunnels

with a total length of nearly two miles

underneath Greenland's ice.

All powered by a nuclear reactor.

To the public, it's a climate research base.

But Camp Century is actually the location of a top secret initiative

called Project Iceworm, whose goal is to establish

a missile launch site within easy striking range of the Soviet Union.

All hidden beneath the ice and capable of unleashing 600 nuclear warheads.

- How did they go about that? - They didn't understand

the fundamental properties of the ice.

[Andrew] So, they went there and funded a lot of really incredible science

to study what ice does. How it behaves.

[Jeremy] To do this, they drill a mile down

deep into the Greenland ice sheet.

They recovered all these cylinders of ice in about 1.5 meter long segments.

[Jeremy] And what they learn forces them to abandon their hopes

for a missile launching base.

The problem is ice is really not very stable.

It changes, it warms up, it melts, it solidifies.

And it's a really bad thing to put nuclear missiles

on an unstable, ice surface

that can move around, potentially damaging those missiles.

[Jeremy] With the added weight of falling snow,

tunnels that start as 20 feet wide slowly collapse.

Sort of like when the walls in the trash compactor scene in Star Wars happens.

Slowly over time it started to compress in.

[Jeremy] But with the end of the Cold War, America's need for a missile site

at Camp Century comes to an abrupt halt.

But 60 years later,

the discovery of the long-missing Camp Century ice core

warns of a new and potentially more devastating threat.

What else is to be revealed about this top-secret base?

[Jeremy] Using advanced analytical techniques,

[Jeremy] Using advanced analytical techniques, Drew probes the sediment at the bottom of the Camp Century ice core.

Drew probes the sediment at the bottom of the Camp Century ice core.

[Dijanna] Ice cores record history.

They give us a little stamp on what was happening in the atmosphere

and the environment at a given time in the past.

The further down you drill into the ice, the further back in time you are going.

[Jeremy] What Drew finds at the bottom

of this time capsule is truly mind-blowing.

[camera shutter clicking]

It was one of the eureka moments.

I thought that that didn't happen to scientists.

I thought that was just something that happened in movies.

[Jeremy] In the sediment are traces of plant fossils,

proving that within the last million years, Greenland was once ice free.

For the first time, we saw just how dynamic Earth's climate can be,

um, and how quickly it could change.

We knew that this was a new chapter in the story of Camp Century.

[Jeremy] This discovery proves that Greenland

is more susceptible to climate change

than we previously thought.

It's not a case of if the ice sheet is melting,

but how fast.

[camera shutter clicking]

[Jeremy] The ice core exposes a very real threat

to all those people who live along the coasts of the world's oceans.

[Andrew] It's a massive store of frozen water

that can raise sea level as much as seven meters.

As a scientist, this sort of information is really fascinating,

but of course, as a citizen and a human living on this planet, it's horrifying.

[Jeremy] All this from a scientific analysis

of a long-forgotten ice core sample.

And the discovery of the microscopic evidence hidden inside.

[Rob] Camp Century has been invaluable for science,

but not in the way that it was intended.

[Jeremy] The legacy of US nuclear ambitions in Greenland

reveals a critical and unexpected truth about our oceans,

one that may help scientists help us combat the threat of climate change.