All language subtitles for D D S01E02 Earthquakes 1080p AMZN WEB-DL DD2 0 H 264-playWEB_track3_[eng]

Deadly...

highly destructive,
and impossible to predict.

Earthquakes are one
of Mother Nature’s

most terrifying forces.

Every year,
there are half a million

detectable earthquakes.

Only 100,000 of those are
strong enough to be felt.

But 100 of them are so powerful

that they cause damage,
injury and even death.

The world’s surface
is not solid.

It’s made up of separate
tectonic plates

that are constantly moving
and shifting.

Sometimes the edges get caught
against each other,

storing up huge amounts
of energy.

When that energy is released,
the forces can cause chasms

to open in the ground
and buildings to collapse.

With eyewitness accounts

and fascinating
expert insights,

we investigate a catastrophic
magnitude 7 earthquake

that struck Haiti
on the 12th of January 2010,

as well as two earthquakes
that occurred in Mexico City

exactly 32 years apart,

and see how lessons learned
from the 10,000 deaths

in the first disaster helped
to save lives in the second.

First, in this episode
of Deadly Disasters,

we’ll focus
on the horrific earthquake

that struck Haiti in 2010.

Located on the West Indian
island of Hispaniola,

Haiti is one of the poorest
nations in the world.

More than half its citizens
survive on less than $2 a day.

It has a population
of nearly 10 million,

many living
in makeshift dwellings.

Non-profit organizations
like ECO Works

have been helping
Haitian communities foster

infrastructure development
since 2008.

The infrastructure was
what it is,

unfortunately, still today,

which is that for people
who live in poverty,

which is the greater majority
of the population,

they don’t have access to power,
to water or to sewage.

The country is no stranger
to natural disasters.

In 2008, it was hit
by four hurricanes

which caused flooding,
landslides,

and left 800 people dead.

This impoverished country
was still struggling

to recover
from those hurricanes
when they were struck

by one of the world’s
worst natural disasters.

Just before 5:00
in the evening,

on the 12th of January, 2010,

Haiti was suddenly rocked
by a magnitude 7 earthquake.

It was the most powerful
earthquake

to hit the area
in more than 200 years.

Basically, earthquakes
are the result

of the movement
of the earth’s plates.

The plates move because of
the internal heat of the earth

which moves them around.

And the plate boundaries,

where the plates
meet each other,

that’s where
you can generate earthquakes

because you got giant fractures
in the earth’s crust,

and those are moving
very slowly...

They’re moving
at about the same rate
as your fingernails grow,

which is from millimeters
to centimeters per year.

But eventually,
the stress is so high

that it overcomes the friction

and then the fault moves
very rapidly,

a couple of meters per second,
and that would then

generate the earthquakes,
which travel as waves

through the solid part
of the earth.

The epicenter
of this cataclysmic event

was below
the city of Léogâne,

about 25 kilometers from
the capital, Port-au-Prince.

The earthquake was unusually
near the surface,

occurring at
a depth of only 13 kilometers.

This dramatically increased

the level of shaking above.

Port-au-Prince in Haiti is
very close to a plate boundary

called a Gonâve Microplate
and that southern boundary

stretches all the way
from Jamaica.

In fact, it goes all the way
through the center of Jamaica

and then goes all along

the southern peninsula of Haiti

and passes very close
to Port-au-Prince.

Shocks quickly spread
throughout Haiti

and the neighboring
Dominican Republic, as well as

to parts of the nearby
Caribbean islands of Cuba,

Jamaica and Puerto Rico.

Roughly three million people
were affected

by intense shaking
that was strong enough

to cause
damage to buildings.

The closer they were
to the epicenter,

the more destruction
occurred around them.

The capital, Port-au-Prince,
and the densely populated

surrounding areas
didn’t stand a chance.

The same amount of energy
as 35 atomic bombs,

like the one that destroyed
the city of Hiroshima,

was released in 30 seconds
of intense shaking.

Port-au-Prince was simply
ripped apart.

What shocked me the most
is the magnitude

and the horror
of the devastation.

It was just unimaginable.

It looked like a war zone.

People were crying,
people were looking

for loved ones
under the rubble,

sometimes with their bare
hands, trying to get them out.

It was really extremely painful
and hard to live through.

You cannot find no person
alive down this house.

No life.

The Haiti earthquake
was a magnitude 7,

which classed it
as a major earthquake.

But how exactly are
earthquakes measured?

Earthquakes are measured either
by the energy they release

or by the damage
they are doing.

The energy that is released
is measured with instruments

that we call seismographs,
and they measure the amount

of energy that it released.

There’s a certain distance,
graphically,

that you can see the
different waves that travel.

And from the distance and
the amount of energy released,

we can determine the magnitude
of the earthquake.

Previously, we used what was
called the Richter scale.

And that’s the most famous
everywhere around the world.

They still talk
about the Richter scale.

And so, actually,
the modern magnitude,

what we call
the "Moment Magnitude",

is actually based
on the Richter scale.

The reason they did this
was because

people already knew
what the Richter scale was,

and so, if you have
an idea of--

Okay, there’s a magnitude 5.

Okay, so we have
a moment magnitude,

we put it very similarly

to magnitude 5
from the Richter scale.

So then it looks the same.
And people know what it is.

The damage from
this magnitude 7 earthquake

was particularly devastating
in Haiti.

One of the problems
in the 2010 Haiti earthquake

was the quality of
the construction was very poor.

Much of
the construction was informal,

there were no inspections
of the buildings

and there was also the use
of cement-sand mixtures,

they were trying
to stretch the cement

so they mixed it
with either too much sand

or sometimes sand
that had salt in it,

so that the cement
was not very strong.

When the earthquake struck,

thousands of buildings
collapsed,

killing or trapping
their occupants inside.

While such a powerful
earthquake

could be expected
to cause destruction,

experts were shocked

by the catastrophic failure
of so many buildings.

Even new and renovated schools,
police stations...

bank branches,
high-end hotels, and hospitals.

Some seismologists sort of
have a saying

that "It’s not earthquakes
that kill people,

it’s buildings
that kill people."

The cathedral and the
national palace

were in ruins.

The national prison
in Port-au-Prince

was so badly damaged

that 3000 dangerous criminals
were able to escape.

The damage happens
when you are within buildings

that are not built
according to code

or fortified for earthquakes,

so the infrastructure
that is not well prepared

for an earthquake
is more dangerous

than the earthquake itself.

In 1989,

a comparable earthquake

occurred in San Francisco,

but resulted in the loss
of only a single life.

The difference in that instance
was infrastructure.

Haiti simply lacked
the same building standards,

resulting in
more widespread devastation.

These were
two similar earthquakes

with hugely disproportionate
consequences.

In the town of Léogâne,

right above
where the earthquake occurred,

90 percent of the buildings
had simply ceased to exist.

While in the small coastal
fishing port of Petit Paradis

on the west coast of Haiti,
a tsunami wave swept inland,

dragging several people
to their deaths.

Haiti was still trying
to recover from the effect

of the hurricanes
two years earlier.

In the face
of this latest catastrophe,

the country was unable to cope.

Vital services needed
to relieve the stricken country

were either damaged
or destroyed.

What is the definition
of a disaster

for professionals like myself?

It is an event that is
of such magnitude

that the local
or the national government

cannot face it alone.

Efforts to get food,

medical aid
and water to the survivors

were hindered by the breakdown
in communication systems.

Add to this, the fact
that in the same year

the earthquake happens
in January, in October,

there is a cholera epidemic,
that was brought in

by a contingent
of the United Nations.

Now 800,000 people are sick,

and more than 10,000 die.

So when you talk about
the logistics and the magnitude

of what we were dealing with,
it was beyond imagination.

Although the runways
at the Toussaint Louverture

International Airport
were intact,

damage to the control tower

meant that planes
couldn’t take off

or land safely.

At the main seaport,
piers had collapsed

and cranes had been knocked
over, so ships were not able

to unload
urgently needed supplies.

Almost all paved roads
were blocked,

due to severe surface damage,

fallen trees and debris
from collapsed buildings.

In the hours
following the quake,

survivors dug through rubble,
often with their bare hands,

to rescue family and friends.

Dusk fell just two hours
after the earthquake.

In the eerie darkness,

rescuers had to use flashlights

as they continued
to claw at the rubble,

trying to reach
those trapped beneath.

Everywhere is dark, she’s just
like an incredible bright star

in the middle of this darkness
and it’s a wonderful feeling.

That night,
many people in Haiti

were forced to sleep
on the streets,

either because their homes
had been destroyed

or because they were
terrified of aftershocks.

When a fault moves
and causes an earthquake,

it changes the distribution of
the stresses around the fault,

so aftershocks are generated.

They’re usually smaller
than the main shock

but there have been
cases where

they’re almost as large
as the main shock.

As daylight broke
on the morning

following the earthquake,

it became clear that thousands
were either injured

or had lost their lives.

Most of the wounded
had nowhere to go.

Medical centers had either
been destroyed

or were out of action.

A lucky few were treated
at the only hospital

operating in Port-au-Prince,
a mobile field hospital.

By chance, the hospital
had already been set up

by the Argentine Air Force,

who were part
of a U.N. peacekeeping mission

stationed there.

During the first night
after the earthquake,

staff managed to treat
1000 wounded survivors.

Helicopters airlifted
those most gravely injured

to Santa Domingo
in the Dominican Republic.

Doctors and nurses who had
survived the earthquake

set up makeshift triage centers

in parking lots
and other open spaces.

Medics attended to the worst

of the injuries
as best they could.

As the sun beat down
on the car park

of the Hospital de la Paix,
those waiting to be treated

lay among those
who were already dead,

while others, with wounds
open to infection,

could only sit at the roadside,

hoping that help would arrive.

Later, China announced that

a 50-member rescue team
would be sent to Haiti.

But as the hours passed,

the horrific scale
of the devastation

was becoming all too clear.

The Haitian president,
Rene Prevail,

told reporters
that he believed over 100,000

may have perished
in the earthquake.

Many of the dead were hastily
buried in mass graves.

The presidential palace

and many other
government buildings

had been smashed,
hampering the country’s

already unsteady
central government.

Those who survived
and who were civil servants,

they also suffered tragedy,
so given this situation,

which was so painful
and so beyond imagination,

I actually give very high
points to the government

because they did regroup
quite quickly

and they tried to coordinate
as much as they could.

Haiti was a country
that had ceased to function.

This terrible disaster

was turning into
a horrific nightmare.

Thankfully, towards
the end of the day

after the initial earthquake,

the first international
aid agencies began to arrive.

Commandos of U.S. Air Force
Special Operations

managed to land at the airport
in Port-au-Prince.

Due to the damaged
control tower,

no aid flights had been able

to bring relief
to the survivors.

Haitian authorities
handed the airport

over to the U.S. officials,
who were able

to allow aid flights
to land the following day.

The U.S. army did very well,

and so that helped a lot

on the distribution
of the aid that came--

food, water
and everything else.

A week after the earthquake,

some aid had reached
the capital

but in the rest of the country,

people were still fending
for themselves.

Even before the disaster,

only half of Haitians
had access to clean water.

Now that supply
had been cut off.

People searched the streets

carrying empty plastic bottles,

gathering water from broken
pipes and gutters...

wherever they could find it.

With food running out,

some thirsty and desperately
hungry people

began to forage for supplies
among the ruins.

The United Nations,
who were at the forefront

of the initial response,

already had a presence
in Haiti.

But they had suffered
many casualties as well.

Their headquarters
had collapsed,

and about 150 U.N. personnel,

including the head
of the peacekeeping mission,

were unaccounted for.

The initial response led

by the new acting head,
Edmond Mulet,

was criticized for being
too focused on security.

They were concerned
about the 3000 inmates

who had escaped
from the collapsed jail

in Port-au-Prince.

The UN wanted to find

the escaped criminals

and maintain public order.

Struggling Haitian police
regrouped and attempted

to deal with the increasingly
chaotic environment.

Several days
after the initial earthquake,

exhausted rescue teams
continued to comb

through the rubble,
desperately searching

to find anyone left alive.

Although some people
had been miraculously rescued,

hope of finding
any more survivors

was rapidly fading.

Despite more and more aid

finally arriving
to the country,

it was not enough to deal

with the ever more
desperate situation.

Emergency medical teams
were working

out of shipping containers,

performing lifesaving
amputations,

and urgent calls went out

to U.S. medical schools
for extra volunteers.

If you have teams that are
prepared to get people

to safe places, to treat
people who are injured

or damaged
in some medical way...

you’re gonna reduce
the death toll enormously.

Preparation is the key
to reducing

the negative effects
of any natural catastrophe.

As aftershocks rocked an area

15 kilometers
west of the capital,

aid officials feared that
if help could not be delivered

to the three million survivors

still fending
for themselves,

there would be a total collapse
of law and order.

U.S. Marines on troopships
began disembarking in Haiti

to assist the struggling
relief effort.

They brought much-needed
heavy equipment,

as well as other
urgent supplies.

You need to have
the right equipment

for the particular
kind of problem

that you’re dealing with, right?

Whether it’s robots
that help you find people

that are buried
in an earthquake, or whether

it’s water purification
systems, et cetera.

And the right meds for the most
likely types of scenarios

that you’re going to encounter
in these events.

Aid distribution was chaotic.

U.S. helicopters unloaded
boxes of ready-to-eat meals.

They contained powdered food,

but to the Haitians,

they just looked like
packets of dust.

Many people threw them away

because no French
or Creole-language instructions

explained that they needed
to be prepared

by mixing with water.

Despite the fact
that the airport was open,

aid groups complained
of long delays

in getting vital supplies
of food, water and medicine.

Médecins Sans Frontières--
Doctors without Borders,

reported that its cargo plane
with 12 tons

of urgently required
medical supplies,

had been turned away from
the congested airport
three times.

One doctor reported
that they had been forced

to buy a saw
from a local market

so that they could continue
to perform amputations.

With 16,000 boots
on the ground,

the U.S. Army reported

that 400,000 bottles of water
and 300,000 food rations

had been delivered
since they first arrived

on the scene the day
after the earthquake.

With over a million people
left homeless,

those displaced in urban areas
were forced to shelter

in flimsy makeshift camps.

Only around 130 people
were rescued

from collapsed buildings
by international rescue teams.

Two weeks after
the initial earthquake,

the search for survivors
was largely abandoned,

and all efforts now focused
on retrieving the dead.

250,000 to 300,000 die,

300,000 are injured

and 1.5 million are homeless.

Although billions were raised
through international efforts

from both government
and charitable bodies,

Haiti is still gripped
by grinding poverty

and underinvestment.

But the fact that young people
are now being trained

in safe building practices

shows that Haitians are trying
to learn lessons

from those terrible events.

Proper training
of the local population

is crucial to the success of
any emergency response effort.

Regular drills
must be undertaken

to ensure that people
are adequately prepared

for the likely event that
another deadly earthquake

will strike in the future.

When it comes to lessons
learned from past disasters,

few places can rival the city

that we focus on next
in this episode.

On the afternoon of the 19th
of September, 2017,

a magnitude 7 earthquake,
the same force

as the one that struck Haiti,
hit Mexico City.

Dozens of buildings collapsed,

and a total of 369 people
lost their lives.

But in 1985, exactly 32 years
prior to that day,

an earthquake in the same city

caused more than 400 buildings
to collapse,

killing over 10,000 people
and leaving 5 million

with no power or water.

In the last 35 years,
we have had

two very important events
in Mexico City.

One was the ’85 earthquake.

That earthquake was
a subduction earthquake.

It was produced on Lazaro
Cardenas in Michoacan

around 250 kilometers
from the city.

That earthquake
was very destructive,

we had a lot
of damaged buildings

and a lot
of collapsed buildings.

A lot of people died
in that earthquake

and it was combined with
the aftershock the day after.

So it has been

the most destructive
earthquake in the city.

Why was there so much
more death and destruction

in the 1985 earthquake?

The difference
between the two disasters

has been largely attributed

to a change
in the building regulations

and the introduction
of an early warning system.

XYOLI PERéZ:
So after the 1985 earthquake,
the Michoacan earthquake,

there was the need
of establishing

an early warning system
for Mexico City.

In the early hours of the 19th

of September, 1985,

just as millions of people were
getting ready for their day,

Mexico City was struck
by a magnitude 8 earthquake,

one of the most powerful
ever to hit the area.

It was also one of the longest.

The terrified inhabitants
had to endure intense shaking

that lasted
for nearly three minutes.

The quake extended
over a vast area.

According to the U.S.
Geological Survey,

tremors were felt as far away
as Guatemala City

and Houston Texas, over 1500
kilometers from the epicenter.

The quake occurred along
a vast subduction zone

which is part of
the Middle American Trench.

This is the eastern part
of what is arguably

the most dangerous series of
fault lines in the world--

the Ring of Fire,
a volatile strip which runs

in a 40,000-kilometer horseshoe

around the edge of New Zealand
in the Pacific Ocean,

passing Indonesia,
the Philippines,

Japan and Russia,

across to Canada,
the Pacific coast of America,

Mexico and down the eastern
coast of South America.

Roughly 90 percent
of all earthquakes

occur along this ring.

Although, the epicenter
of the earthquake

was in Michoacán...

the majority of the damage
occurred in Mexico City,

over 300 kilometers away.

How could an earthquake
so far away

prove to be so catastrophic?

The answer lies
in the very dawn
of civilization,

when the Aztecs
settled in Mexico

and developed a vast empire.

They created their capital

on two small islands
in Lake Texcoco.

By 1519, it was home

to an estimated
400,000 inhabitants.

When the Spanish
conquered the Aztecs,

they destroyed the city

and built a new one
on the ruins.

After Mexico’s independence,

this ancient site
became its capital.

Mexico City, it’s a very
unique place in the world.

It sits atop
a lake bed zone,

very high water content.

We call them
saturated soil.

That lake was drained
over time.

The 1960s is
when it was drained

100 percent,
the lake is gone.

Unfortunately,
what that meant is

people moved into that area

as the lake was drained,

so now people live where
there used to be a lake.

What that means is,
for earthquakes,

is that it amplifies
the signal greatly
because it’s a basin

and they’re basically sitting
on what used to be mud.

We study the subsidence,

so what happens is,
in Mexico City,

because of the lake sediment,
is moving downward

every year
by about 35 centimeters.

In every place in the world
that they study seismology,

they talk about Mexico City.

The earthquake caused

widespread catastrophic damage.

Several old hotels, including
the Regis, Versailles,

and Romano fell to the ground.

Gas mains were fractured,
causing fires and explosions.

Many multi-story buildings
collapsed completely.

Nearly 7000
were seriously damaged.

Fortunately, the quake struck

when many were still
commuting to work.

Thirteen hospitals
were destroyed.

In the immediate aftermath,
40 percent of the population

in Mexico City
had no electricity,

45 percent were without water.

President Miguel de la Madrid
initially refused offers

of help from
the international community.

He said that Mexico was well
able to cope

with the disaster on its own.

Volunteers from areas
of the city

that had escaped
largely undamaged

went to the aid
of their fellow citizens

who had not been so fortunate.

Residents spontaneously
organized themselves

into brigades, such as
the Moles Rescue Brigade,

to help in the search
for survivors.

We never knew each other.

We started helping
in the collapsed structures

and started working
and making friends and telling,

"Well, we’ll meet
here tomorrow

and we’ll start working."

There were extraordinary
scenes of unity

from the city’s inhabitants,

where many lent a helping hand
to their neighbors.

We started working
with the people

to save people
and their belongings.

Overall, there was
a feeling of solidarity,

which was remarkable
in such a vast, sprawling city.

As the scale of the disaster
became evident,

thousands took to the streets
in protest,

demanding assistance.

Following the demonstrations,

the government’s attitude
to foreign aid softened.

Mexico began to accept offers

of money and help
from many countries.

Five days after the earthquake,

Nancy Reagan
visited the stricken city.

She delivered
a letter of sympathy

from the U.S. president

and a down payment
of $1 million

on future American aid.

Hope of finding
any last survivors faded.

It was thought that
no one could remain alive

under the fallen masonry
for more than a week.

But rescuers working
amongst the tangled wreckage

of a maternity hospital
were convinced

that there were still people
left alive in there.

What happened next
came to symbolize

a spirit of resilience
and togetherness

in the face
of terrible adversity.

The 12-story tower
of the Juarez Hospital

was built in 1970.

At the time of the earthquake,
the hospital was nearly full,

and more than 700 patients
and doctors

were believed to have been
trapped inside.

Rescue teams
from several countries

as well as volunteers and
family members of the victims,

worked non-stop for days,
searching for survivors.

Many bodies
had already been found,

but with the help of ultra-
sensitive listening devices,

people heard noises that gave
them a small glimmer of hope.

Images of rescue workers using
pickaxes to dig their way

to buried survivors were
beamed around the world.

A week after
the hospital collapsed,

an 8-day old baby girl
and a 33-year-old man

were pulled alive
from amongst the rubble.

As dusk fell, another infant

was pulled alive
from the wreckage.

In all,
more than a dozen babies

were rescued
from the collapsed hospital.

They became a symbol of hope

for a devastated nation

and have been known ever since
as the ’miracle babies’.

Across Mexico City, many people

were rescued alive
from the debris.

While thousands received
medical treatment,

5000 bodies were recovered

from the rubble
of the shattered city.

But those were
only the total number

of legally certified deaths.

Approximately 250,000 people
were left without shelter.

The total cost of the disaster
to the Mexican economy

was estimated to be
more than $4 billion.

In the first weeks
after the earthquake,

720,000 tons of debris
were removed.

The disastrous 1985 earthquake
led to the introduction

of much tougher building
regulations,

equal or superior
to those found

anywhere in the world,
and to the formation

of well-trained emergency
search-and-rescue brigades.

Well, there’s a lot
of challenges

with disaster preparedness.

The challenges involve
trying to figure out

which disaster is more likely
to cause more damage.

What is the chance
that something can happen,

and if it happens,
how bad is it likely to be?

The catastrophe also resulted
in the establishment

of a seismic alarm system which
provides advanced warning

whenever it senses movement
on the Pacific Coast.

The main idea of the early
warning system is that

we have a lot of devices
that measure the movements

along the Pacific Coast
and the idea is,

when those devices record
a very large motion,

they send a signal
to Mexico City.

So, the idea is
you could use that

to give a little bit
of warning to people

for when the real hammer
of the surface waves arrive.

The early warning system

received a major test

on the night of the 7th
of September, 2017.

Mexico was rocked by a powerful
magnitude 8.2 earthquake,

nearly 725 kilometers
from Mexico City.

The early warning system worked
exactly as planned.

Sirens went off
a full two minutes

before the first tremors
reached the city.

Buildings shook,

but the earthquake
was so far away

that there was little damage.

Twelve days later,

Mexico City took part
in the annual drill

to mark the anniversary of
the fateful 1985 earthquake.

Sirens wailed
but the atmosphere was calm.

After all,

this drill
happened every year.

When the sirens went off again
a few hours later,

many believed it was still part
of the earlier drill.

But they were wrong.

Within seconds,
the city was struck

by a magnitude 7.1 earthquake.

The intense shaking lasted
for only 20 seconds,

but in that time,
over 40 buildings collapsed,

hundreds were killed,
and thousands injured.

It was 7.1 on magnitude scale
but it was too near.

It was just like 120km
from the center of the city.

That means that from the south
part of the city,

because the city is very large,

it was just like 100 km,
for example, from Xochimilco.

We have movements
in differing ways,

which cause a lot of problems
to infrastructure,

to buildings, to the metro
system over there...

In the neighborhood
of Roma Norte,

an entire office building
collapsed.

Survivors were taken
to hospital

but there were fears
that many people

were still trapped inside.

Construction workers from
a nearby site rushed to help.

The government quickly declared
a state of emergency.

Federal police
were swiftly deployed

with 3000 personnel
taking to the streets.

From all over
the damaged areas of the city

there were reports
of gas leaks and fires.

Amid the increasing noise
and clamor

of a hectic rescue operation,
it became clear

that the faint sounds
alerting search parties

to the presence of survivors,
could be missed.

Rather than yelling,
rescuers developed

a system of hand signals.

A fist in the air was a call
for immediate silence.

The gesture would be repeated
by everyone around,

silently spreading the message
through the crowd.

The call for everyone
to stop moving

was an open palm in the air.

And a single finger in the air
meant "back to work".

While in parts of the city
that had not been affected,

there was an eerie silence.

Businesses had closed,
and the normally congested

rush-hour streets
were mostly empty.

But there was frantic activity

at disaster sites.

When rescuers arrived
at the Enrique Rebsamen School,

they discovered
a harrowing scene:

Dozens of children
and teachers had been buried

when the three-story school
building collapsed in on them.

As rescuers clawed

at the concrete
with their bare hands,

they could hear
the screams of children

trapped beneath the rubble.

President Enrique Peña Nieto
later visited the school

to mourn the 20 children
and two staff members

who had lost their lives.

Distraught parents
clung to the hope

that their missing children
could still be saved.

But tragically,
only two children

were pulled out
of the wreckage.

In the Condesa area,

a man was rescued after being
trapped under the wreckage

of an apartment building
for 22 hours.

Rescuers had heard him
screaming for help all night.

The Mexican president announced

that the damage caused
by the earthquakes

could cost upwards
of $2 billion.

But while there was loss of
life and significant damage,

it was nowhere near as bad
as in the 1985 earthquake.

Millions of dollars
had been spent

to reinforce older buildings
across the city.

Buildings can be affected
by earthquakes,

but designing them correctly

can eliminate
a lot of the problems.

The construction codes
in Mexico City

actually are one of the most
rigorous codes in the world,

and since the earthquake
of 1985, there has been

a lot of specific points
that were studied by people

from UNAM and
the engineering institute

that are specialists that have
helped the developing

of more rigorous and more
strict construction codes.

In Mexico City,
strict building controls

are only a part of the system
in place to help them

become better prepared
for future earthquakes.

Teams of staff
in the emergency services

practice earthquake simulations
throughout the year

so they can respond
immediately.

But most important
of all have been

the huge public-awareness
campaigns that have trained

the residents of Mexico City
to understand

exactly what to do
when they hear the sirens.

But we are still behind
other cities,

like, for example, Tokyo,

Los Angeles,
and San Francisco,

because in those places, people
and society are more aware

about how earthquakes
can affect the buildings.

For example, in San Francisco,
in the science museum,

they have a complete part
of the museum

dedicated to the earthquakes.

I believe that Mexico can use
those kind of ideas

in order for the people
to get more prepared

and more aware about how
earthquakes can affect them.

However, the safety measure

that would save most lives,

the ability
to accurately predict

when and where
an earthquake will strike,

has proved to be
stubbornly elusive.

In order to understand
the vulnerability of a place,

we need to understand
what is the probability

of earthquakes to occur.

Prediction means that you give

the exact time and place
of an earthquake.

What we can do, just as we do
with the weather,

is we can forecast earthquakes.

Now, we can use
a technology called GPS,

the global positioning system,
to survey the crust

around a potential earthquake fault.

We know that the Earth
is a chaotic system,

and we can say that if we apply
chaos theory here,

we are actually never going
to be able to predict,

because we never knew and are
never going to know what

the initial conditions were
on the Earth, unfortunately.

Now we have
much more equipment,

not just in the earth,
but also in space,

so we can have
a lot of measurements,

and hopefully we could find
some precursor that allows

to make earthquake predictions.

If we could predict
that an earthquake

is going to happen
in 20 minutes,

how useful would that be?

Because it’s not enough time
to evacuate a city.

What we really need
is something

like what we have
for hurricanes.

Ideally, we’ll need
three days’ warning,

which would probably
give us time

to evacuate a large city
like Mexico City.

All we can be sure of is that

some of the world’s
most populous

and economically significant
cities

are situated on or near
seismically active fault lines.

For those cities,
it is not a question

of "if" an earthquake will
strike but "when".

We will always have to live
with the threat

of one of Mother Nature’s
most unpredictable

and deadly forces,

earthquakes.