All language subtitles for Surviving the Tsunami 720p PBS NOVA 2011 HDTV x264 AAC MVGroup EN Sub

MAN (speaking Japanese):

NARRATOR:
Off the coast of northern Japan,

a Coast Guard ship comes
face to face

with a 30-foot wall of water.

NARRATOR:
It is the first sign
of a deadly tsunami

that will soon engulf
Japan's northern coastline.

More than 20,000 people
will die.

Entire towns vanish.

(siren wailing)

As the giant waves reach shore
and sweep inland,

NHK, Japan's national
broadcaster, is on the scene,

capturing events as they unfold.

From pictures of unimaginable
destruction...

To miraculous survival.

Now the people in these images
are telling their own story.

At the far reaches
of the tsunami, a policeman.

A family stranded
on the roof of a building.

A man swept away in his car
lands on top of a bridge.

Scientists in Japan are
intently studying this tsunami

to help people better protect
themselves in the future.

They, too, want to understand

how these victims
managed to survive

when so many others didn't.

What are the lessons
we can learn

about surviving a tsunami?

Right now on NOVA.

Major funding for NOVA is
provided by the following:

Supporting NOVA and promoting
public understanding of science.

And the Corporation
for Public Broadcasting,

and by PBS viewers like you.

(rumbling)

NARRATOR:
March 11, 2:46 p.m.

The eastern half of Japan
was hit by a fierce tremor.

(shouting)

(man over loudspeaker)

NARRATOR:
The port city of Kamaishi
in northern Tohoku,

just after the earthquake hit.

The city's emergency
broadcast system

announced the tsunami warning.

An NHK reporter began filming
on the streets of Kamaishi.

Residents began to head

for the designated
evacuation site,

a hillside overlooking the city.

(siren wailing)

Evacuees gathered
on the high ground.

Fifteen minutes
after the earthquake hit,

this video was taken
from the hillside.

Many people still remained
in the city at this time.

One of the those remaining
was Saeko Kudo.

At the time of the earthquake,

she was at home
with her mother, Toyoko.

The Kudos' home is in the
harbor district of Kamaishi.

The harbor can be seen just
80 meters away from the house.

The high ground where
many people took refuge

is a ten-minute walk.

Even closer was
an eight-story building

that was a designated
evacuation site.

This is the Kudos' home,
facing the harbor.

At the time of the earthquake,
the mother, Toyoko,

had just returned
from a dialysis treatment

at the hospital.

INTERVIEWER:

TOYOKO:

NARRATOR:
Saeko thought they should
evacuate immediately,

but she also felt
it would be hard

for her elderly mother to do so.

This was because a series
of strong aftershocks

was shaking the city.

NARRATOR:
The Kudos did not seek
shelter immediately.

They would soon experience
a terrifying ordeal.

About a half-hour
after the earthquake,

the camera on the hillside
captured the first signs

of the tsunami.

At that moment, Saeko Kudo also
noticed the unusual condition

of the nearby harbor.

(siren wailing)

NARRATOR:
At this time, the water level
was rising steadily,

and water had begun to overflow
the seawalls in the harbor.

But there were still
many people in the city

who were unaware of this.

Machiko Kikuchi felt the tremor
of the earthquake while at work.

She quickly drove home to check
if her house had been damaged.

The house was 130 meters
from the harbor,

but she could not see the
changes taking place there.

Also, because she was
in her car, she did not hear

the emergency announcement
of the tsunami warning.

NARRATOR:
When Machiko got out of her car
in front of her house,

a passerby shouted a warning.

NARRATOR:
Now aware of the danger,

Machiko hurriedly climbed
back in her car.

Saeko Kudo had belatedly decided
to take her mother to a shelter.

When they came out
on the street,

they saw water
flooding in from the harbor.

Around this time,

another taller wave was filmed
as it approached the harbor.

It was flowing
over the breakwater

that was built to protect
the town.

NARRATOR:
The tsunami was now surging
into town with increased force.

The video recorded images of
the Kudos' house being flooded.

The tsunami passed
by the Kudos' house

and spread further into town.

The fierce wave moved quickly,

leaving people in the town
no time to escape.

(rumbling)

NARRATOR:
Machiko's car was thrust
against a neighboring building,

where it stopped
and began to sink.

After seeing the tsunami
approach their second floor,

the Kudos had hurried
up to the roof.

It's an open space that is
partially covered by roof tiles.

The roof is seven meters high,

but the water would soon flood
it with intense force.

NARRATOR:
This is video footage of the
Kudos' house at that moment.

Saeko and her mother
are under the water

and cannot be seen.

(crashing and rumbling)

A human form becomes visible

on the tile roof
of the Kudos' house.

NARRATOR:
Boosted by the water
onto the roof,

Saeko's figure can be seen.

This was the moment she
scrambled up onto the tile roof.

Her mother was still underwater.

NARRATOR:
Mother and daughter were now
up on the tile roof.

They had escaped being swept
away by the tsunami

and survived with their lives.

Around this time,

a woman could be seen
on the roof of a building.

It was Machiko, who had
been swept away in her car.

She had escaped from her car
through a broken window.

She scrambled up the pile
of debris around her car,

grabbed onto the window
of a building

and managed to escape
the tsunami.

40 minutes after
the earthquake occurred.

The videos show how the tsunami,
taking a new form,

continued to attack the city.

A ferocious backwash had
begun to sweep the city.

Around this time, a video
captured the image of a car

that had been lifted up
onto a bridge.

The driver of the car
was Yoshiki Hasegawa.

He had been swept away
by the tsunami,

but came to rest on the bridge
by chance, and survived.

He witnessed the ferocity
of the backwash

from that vantage point.

Now, houses and cars that had
been swallowed by the tsunami

were being pulled out to sea
all at once.

The backwash was so powerful

that it swept a large cargo ship
along in its path.

At this time, the backwash
was sweeping a man and his car

down the river and out to sea.

It was Tsuyoshi Sawada.

He had given up hope
of surviving

the tremendous rush
of the water.

Tsuyoshi was swept
helplessly along,

unable to do anything
to rescue himself.

At that moment, the bridge
came into view.

He could see a man
on the bridge,

and he started yelling for help.

Yoshiki Hasegawa was the man
on the bridge.

This video captured the moment
that Tsuyoshi was rescued.

He is wearing
a light blue jacket.

Yoshiki is pulling him
to safety.

(dog barking)

The two men were saved by
a series of chance occurrences.

But the powerful backwash
of the tsunami

dragged many people out to sea.

These images show

the massive tsunami

as it came ashore
in the northern part of Tohoku.

The sheer wall of the wave sent
up ferocious plumes of water

as it crashed
into the shoreline.

(people yelling)

The height and destructive power
of the tsunami

devastated the towns
along the shore.

How was such a massive tsunami
created in the first place?

This is a GPS buoy
that is positioned

20 kilometers off the shore
of Kamaishi.

It recorded in detail
the rise in sea levels

caused by the tsunami.

Changes in the sea level began

immediately
after the earthquake occurred.

The sea level began
to rise gradually.

20 minutes after the earthquake,

the sea level had risen
two meters.

Just after that, a startling
phenomenon occurred.

The sea level rose dramatically

and quickly reached
seven meters.

The tsunami took the shape
of a sheer, steep wall.

This rapid transformation
had never been observed before.

Up until now, it was believed
that tsunami were caused

by the following mechanism.

Off the coast of Tohoku,
the oceanic tectonic plate

thrusts under
the continental plate.

Stress builds up
in the continental plate

until it snaps,

lifting the seawater above
to form a tsunami.

But this would form
a gently rising tsunami,

not one that suddenly rose
in height.

Why was it that the tsunami
took the shape of a sheer wall?

Yoshihiro Ito
of Tohoku University

has offered a new hypothesis.

Ito has used underwater
research vessels and other means

to survey the ocean floor

along the coast
of the northern Tohoku region.

This footage was taken
three years ago.

It shows how sediment has
accumulated in the area

where the oceanic plate
is submerging.

Ito believes this stratum
of hardened mud

might have been the reason
the tsunami became so massive.

His surveys have confirmed

that there is a hard layer
of sediment

several kilometers thick
above the plates.

The internal structure of that
stratum has also been clarified.

Many faults called splay faults,

extending from
the plate borders,

have been found within
the stratum of sediment.

Ito postulates
that this mechanism created

the massive tsunami.

The continental plate snaps,

creating
a two-meter-high tsunami.

The energy of the plate movement
is transmitted

to the stratum of sediment,

causing a large vertical
movement in the splay faults.

As a result, the sea level
above the stratum rises

and a seven-meter-high sheer
wall of a tsunami is created.

The tsunami that was measured
at seven meters offshore

more than doubled in height
as it approached the shoreline.

(people yelling)

The massive tsunami was
more than 20 meters high

when it reached the northern
shores of the Tohoku region.

The increased height of the
tsunami resulted in destruction

that far surpassed expectations.

Reinforced concrete
and steel frame buildings

that were considered likely
to survive a tsunami

were destroyed,
one after another.

Why was the tsunami
so destructive?

Clues were discovered in video
footage of the tsunami.

This is the city of Kuji
on the coast north of Kamaishi.

A sewage processing plant,
the white building,

was struck directly
by the tsunami.

Taro Arikawa, of the Port
and Airport Research Institute,

came to Kuji to survey
this building.

A 15-centimeter-thick
reinforced concrete wall

was destroyed by the tsunami.

It had vanished.

Arikawa's attention was drawn

to the white portion
at the tip of the tsunami

just before it hit the building.

This is a phenomenon called
a supercritical flow,

which occurs when
a tsunami crashes.

It only occurs when waves
are very high,

and it has rarely
been seen in Japan.

How much destructive power
does a supercritical flow have?

An experiment was conducted
in a large apparatus

called a wave flume.

This is a simulation
of a 2.5-meter-high tsunami.

The front of the tsunami crashes
and becomes a supercritical flow

as it nears shallow water
along the coast.

Sea water falls
from a high position,

and the speed of the flow
triples in an instant.

The destructive force
of the tip of the wave

increases in proportion to the
height of the incoming wave.

The force of a 2.5-meter
tsunami was measured

at 14 tons per square meter.

This is strong enough
to destroy a concrete wall.

The massive tsunami hit
the northern part of Tohoku

with ferocious strength.

In the flatlands in the southern
part of Tohoku,

it caused a very different kind
of devastation.

In this region
of relatively flat plains,

a tsunami was not predicted

to spread more than
a kilometer from the sea.

However, on March 11,

the tsunami reached more than
five kilometers inland

and flooded a wide expanse
of terrain.

This video shows
the Sendai Plain

about an hour after
the earthquake occurred.

The black water appears
to crawl across the land.

It proceeds without cease,

swallowing up houses
and fields in its path.

In this area,

the tsunami reached a full six
kilometers inland from the sea.

Why did the tsunami reach
such a distance inland?

Ikuo Abe,
of Fuji Tokoha University,

has performed simulations
of the tsunami

that attacked the Sendai Plain,

using measurements that were
made throughout the area.

During the earthquake,

the hypocenter region
where the plate snapped

covered an area 450 kilometers
north-south

and 200 kilometers east-west.

The earthquake caused upheavals
in the sea level

across a wide stretch
of the ocean.

Offshore of the northern part
of the Tohoku region,

the earthquake created
the towering, sheer tsunami

that struck Kamaishi.

To the south, off the coast
of Miyagi Prefecture

and the southern Tohoku region,

the sea level swelled into
several massive, wide tsunami.

The sheer tsunami
and the wide tsunami

overlapped in Sendai Bay,

and the reinforced, powerful
wave headed for the plain.

About one hour after
the earthquake occurred,

the tsunami reached
the Sendai Plain.

It pressed inland
for about 20 minutes,

with massive amounts of seawater
flooding deep into the plain.

The town of Yuriage
in Miyagi Prefecture

was flooded by the tsunami
deep inland.

Residents cannot see
the ocean from the town,

and many were not aware
of the tsunami

until it appeared
before their eyes.

This residential district
is one kilometer from the sea.

Naoki Ishikawa,
a university student,

came outside his house with his
family after the earthquake.

The earthquake had knocked out
electricity in the area.

The family could not watch
the news on television,

and they did not hear the
emergency announcements outside.

Naoki was alerted to the tsunami
by the shouts of his father.

Naoki immediately ran up to
the second floor of his house.

Naoki's house was swept away
by the tsunami,

but he managed to cling
to the roof and thus survived.

But his parents and sister,
who were also at home, perished.

There is no high ground
in Yuriage.

There were four designated
evacuation sites,

including the elementary school.

At the sites, a considerable
distance from the ocean,

there was confusion about
the tsunami warning.

This is the Yuriage
Elementary School,

the evacuation site
furthest from the shore.

After the tsunami warning
was issued,

the children took shelter

on the third floor
of the school building.

Akiko Tanno came to the school
to pick up her daughter,

who is in first grade.

She then took shelter
at the school.

Electricity was out
at the school,

and the tsunami warning
announcement could not be heard.

The only sources of information
for the assembled parents

were the radio and TV reception
on their cell phones.

Just after the earthquake hit,
the Japan Meteorological Agency

announced that the tsunami
would reach Miyagi Prefecture

at 3:00 p.m.

However, 30 minutes
after the predicted time

of the tsunami's arrival,

there was no sign of a tsunami
in the vicinity of the school.

Teachers and parents began
to feel a sense of relief

that the tsunami was not going
to hit the area of the school.

Children and their parents
began to go down

from the third-floor shelter
to the gymnasium.

In fact, the tsunami
reached shore

in the northern end
of Miyagi Prefecture

at the predicted time,
around 3:00 p.m.

It then headed across
Sendai Bay toward Yuriage.

The tsunami reached the shore
just about the time

the children had finished moving
down into the gym.

This bridge is about 800 meters
from the school.

A policeman was seen
standing on the bridge.

He was responding to a traffic
accident that occurred

because of the earthquake

when he was surrounded
by the tsunami.

This photograph was taken
by Hideo Moriya

near the school
around that time.

The tsunami is not visible,
but there is smoke rising

from the residential district.

After a short while,
the tsunami appeared,

carrying tons of debris
in its path.

Hideo quickly ran to take
shelter in a building.

More than an hour
after the earthquake,

the tsunami approached
the elementary school.

At that moment,
one of the parents realized

the tsunami was coming.

Michiru Kusaka happened to be

on the second floor
of the school,

and she sighted the tsunami.

There were more than 100
children and parents

in the gymnasium.

Hearing Michiru's warning,

parents grabbed their children's
hands and rushed for the exit.

(shouting)

This video was taken
from the school building.

The tsunami flooded the spacious
schoolyard in an instant.

Water flooded from the
schoolyard into the gymnasium

just after the children
had all fled to safety.

The children and parents
had climbed

to the roof
of the school building.

Their lives had been endangered
by conflicting information

about the tsunami warning.

All of the designated
evacuation sites in Yuriage

were flooded by the tsunami.

Having lost their refuge,

people headed for an expressway
three kilometers from the ocean.

The expressway is
eight meters higher

than the surrounding area,

and is the only high ground
in the district.

Kazuhiro Numata was one of those
who headed for the highway.

He loaded his daughter and his
elderly mother in his car.

He could see the tsunami
in his rearview mirror.

However, the expressway
was being inspected

for earthquake damage,
and the entrance was closed,

causing a traffic jam.

Some people got
out of their cars

and scrambled up the hillside.

Kazuhiro finally made it
to the vicinity of the highway.

The tsunami was now
just behind his car.

He made a quick decision

and crashed through
the toll booth gate

and up onto the highway.

The massive tsunami struck

the northern coast of Tohoku
and the southern region

in different but equally
devastating ways.

The number of the dead
and missing

totaled more than 24,000.

Those who survived
that harrowing day

shared their thoughts with us.

Yoshiki Hasegawa,

who was in his car when it was
swept away by the tsunami.

Coming to rest on a bridge,
he managed to survive

but saw many people in houses
swept out to sea.

Akiko Tanno came
to the elementary school

to pick up her daughter.

She now regrets
leaving a safe spot,

despite the fact

that a tsunami warning
was in effect.

Saeko Kudo, who was swallowed
by the tsunami

along with her mother.

Saeko knows people
have many reasons

for failing to take shelter,
thinking,

"This city is prepared
for a tsunami,"

or, "My parents are elderly."

These thoughts must be replaced

with a strong determination
to escape.

Saeko agreed to be interviewed

because she wanted
to convey this message.

How can we build
upon the experiences

of people who survived that day,

so that those sacrifices
will not be repeated?

In order to protect
precious lives,

it is incumbent on each of us
to answer this question.

The exploration continues
on NOVA's website,

where you can watch
any part of this program again.

Examine the deadliest
tsunamis of the past

and discover where the next
big one could strike

and what we can do
to prepare for it.

Dig deeper into Planet Earth

with expert interviews,
interactives,

teacher resources and more.

Follow NOVA on Facebook
and Twitter

and find us online at PBS.org.

t WGBH
access.wgbh.org