NARRATOR: Ocean currents control our climate
by transferring heat and moisture from the water
into our atmosphere, thereby influencing
temperatures around the world.
12,000 years ago, as the last Ice Age was ending,
the global ocean currents shut down and much
of the world slipped back into a deep freeze that
lasted for over 1,000 years.
If the ocean currents shut down today,
what would happen to our planet?
Could we survive?
Global ocean currents, which regulate heat and rainfall
around the world, have shut down,
unleashing violent changes in the weather
on both sides of the Atlantic.
Frigid temperatures paralyze much of the Northeastern US.
A year into this catastrophic new weather pattern,
the people of New York City now face the wrath.
Off the coast, a massive cyclone twice
the size and strength of 2012's Hurricane Sandy roars inland.
Monster winds and waves slam into the Statue of Liberty
and then barrel toward shore.
A storm twice as powerful as Sandy is not even conceivable.
Dams of cars will be created in neighborhoods,
subways will be flooded.
This is destruction on a massive scale.
TREVOR VALLE: 30-foot waves and 100-per-mile-per-hour winds
explode through windows and doors,
tearing buildings apart at the seams and dragging
people deeper underwater.
You have rain, wind, chaos, panic, and disorder,
all assaulting a city at once.
It would be panic in the streets.
Some people will be able to survive.
But unless you have the resources and you have
the wherewithal, you won't.
The best thing to do would be to get out.
TREVOR VALLE: As the effects of the ocean current shutdown
spread around the world, no place
is immune from this disaster which
has already killed over tens of thousands of people.
But these catastrophes are just the beginning.
A decade into the disaster, the shutdown of the ocean currents
has set off a series of extreme weather disasters
across the world from superstorms and severe drought
to massive hurricanes and blizzards.
Nearly half a billion people have already died.
As the death toll climbs, temperatures
continue to plunge in the cold regions of North
America and northern Europe.
With warm ocean currents no longer flowing up to the North
Atlantic, the surface water remains cold,
creating frigid temperatures across northern Europe,
with winters that last for 10 months.
Snow falls relentlessly in Germany.
The head of the country's busiest seaport
once used giant ice breakers to get ships into port,
but it's no longer possible to keep up with the deep freeze
and the vital transportation hub shuts down.
Delivery of food and other resources grinds to a halt.
For people who once took their next meal for granted,
like the former head of the Port Authority,
finding food for his family becomes a full-time occupation.
People suffering from cold weather
afflictions like pneumonia and frostbite
begin to overrun hospitals.
In the American Southwest, a severe drought
has ravaged the area.
Fire departments can no longer contain
the wildfires that continue to burn through cities and states.
Another victim is the Colorado River.
It once was the lifeblood of the region,
supplying hydroelectric power and providing
water for millions of people.
Now, it's running dry.
If there's no snowpack and no rainfall,
the Colorado River starts to dry up.
The Colorado River also has a hydroelectric dam.
The human condition is dependent on things
like electricity and water.
You take one of those away, and things fall apart.
TREVOR VALLE: Without water, crops and cattle
have long since died off, and people
are struggling to hang on.
With a lower percentage of Earth's land area
receiving ample amounts of rain, you have starvation
on the very short horizon.
TREVOR VALLE: The future of humanity remains uncertain,
and the effects of the climate disaster are far from over.
You have the prescription for kind of a Dark Age,
a more violent society as those survivors try to scramble
and hold on to what they've got.
TREVOR VALLE: This frightening view
of the future with our ocean currents
coming to a complete standstill is based
on science from the present.
Scientists have been warning that the global ocean conveyor
belt may be slowing down.
For well over a century, the Earth
has been steadily warming.
Experts claim 2016 was the hottest year on record
for the entire planet.
But at the same time, there were also record cold temperatures
in the North Atlantic.
This suggests that as global warming continues
to melt Arctic ice into the sea, this fresh water
is making the cold surface currents less salty and dense
so that they can't sink.
Without this natural process, the world's ocean currents
could eventually shut down.
MAN: We're seeing that right now.
That is ongoing.
Look at the Greenland ice sheet.
It's not only melting more, but it's melting faster.
So this is a concern because that, then,
would provide the large amounts of fresh water
to the North Atlantic Ocean to cause a shutdown.