All language subtitles for D D S01E10 Blizzards 1080p AMZN WEB-DL DD2 0 H 264-playWEB_track3_[eng]

With snow, ice,
freezing temperatures,

and ferocious winds,
the blizzard

is one of Mother Nature’s most
effective killing machines.

But it requires
a particular combination

of warm, moist air rising
through a cold air mass,

which triggers snow
and powerful winds.

These drive the falling snow,

as well as churning up the snow
already on the ground,

to reduce visibility
to practically zero.

And the brutal winds can create
a dangerous windchill

that drops the effective
temperature of the air

to minus-50 degrees Celsius,

killing anyone caught
in its sweeping destruction.

Featuring interviews
from leading experts,

and extraordinary
personal stories of survival,

this episode
of Deadly Disasters

will focus on blizzards
and extreme cold weather events

from all over the world.

Including two historic blizzards

to hit the mid-Atlantic coast
of America,

and a shocking storm that
struck central Europe in 2017.

In meteorological terms,

a blizzard is a very specific
extreme weather event.

It is spawned by an unusual
set of conditions

that create
the fatal combination

of snow and driving wind,

resulting in the dangerously
low visibility

and lethal cold,

which define these freak
weather phenomenons.

One of the most severe
blizzards in recorded history

occurred along the east coast
of the United States

in March of 1888.

Nicknamed "The Great White Hurricane,"

this mammoth
of gale-force winds

and heavy snowfall caused much
of New York City’s streets

to virtually disappear
under the deep snow drifts.

The storm killed more than 200
of the city’s citizens,

and energized
New York City officials

to further invest
in vital infrastructure.

Adjusted for inflation,
the blizzard cost the city

roughly 665 million
U.S. dollars worth of damage.

Blizzards may even occur

when there is little
or no snowfall.

High winds can whip up snow
that is already on the ground,

creating a swirling mass
of airborne snow

that is almost impossible
to see through.

The official U.S. National
Weather Service

definition of a blizzard

is a storm which contains
a large amount of snow,

blown by winds of at least
56 kilometers per hour,

that reduces visibility
to no more than 400 meters

for a length
of three hours or more.

When one or two of these
conditions are forecast,

the National Weather Service

will issue
a "winter storm warning"

or "heavy snow warning."

If all three criteria are met,

they will broadcast
a blizzard warning.

Blizzards pose extreme danger
for a number of reasons.

The winds in a blizzard can be
as powerful as a hurricane.

And just like a hurricane,

if they strike coastal areas,

they can cause
surges of floodwater

that inundate
seaside communities.

Blizzards can last
up to five days,

cutting off communities,

leaving anyone trapped outside
with little or no chance

of getting to safety
or being rescued.

They reduce visibility,
which can also kill,

making travel by car
extremely dangerous.

Dry, powdery snow
that has previously settled

can be thrown into a cloud
by the high winds,

making it impossible
to see anything.

In such a whiteout,
it is extremely difficult

to tell which way is up,
let alone see the road ahead.

The strong winds
and cold temperatures

that go with blizzards
can combine

to create another danger:
the windchill.

Even if temperatures
are already subzero,

windchill can make the
apparent temperature plummet,

making it feel as cold
as -50 degrees Celsius.

It’s terrible.

I can’t believe
that I’m out here, but I am,

because I have to go to work
and I’m a responsible adult now.

That’s what I’m supposed to do.
But it’s super cold.

And as you can see, I’m still
trying to catch my breath.

Expose yourself
to this degree of windchill

during a blizzard,
and some terrible things

will happen to your body.

If a strong blizzard
is forecast,

or if you’re caught
in a blizzard...

So first of all,
make absolutely sure

that you are
really well dressed.

So put as many layers on
as you can.

Because it’s not only the snow,
really, it is the wind,

and the windchill factor
associated with it.

So this is really
what makes you lose heat,

body heat, really quickly.

Bundle up, layer up.
Bundle up, cover up.

If you’ve got to look
ridiculous, look ridiculous.

But stay warm. Keep that wind
off of your skin.

To stay healthy,

we need to maintain

a core body temperature

of 37 degrees Celsius.

A drop of just 2 degrees

can quickly
cause serious problems.

It’s at this time
that hypothermia will set in,

triggering symptoms
like constant shivering,

tiredness and fast breathing.

Drop below
the 32-degree Celsius mark

and you will begin to
experience poor coordination,

slurred speech, confusion
and a clear lack of judgment.

At this point,

your breathing
will start to slow.

If eventually your temperature

falls to below
28 degrees Celsius,

your body will stop shivering.

This is a very bad sign,

as shivering is the body’s way
of trying to keep you alive.

Due to the confusion,

you may not even realize
what’s happening to you.

Bizarrely,
many victims of hypothermia

will start to feel as though
they are burning up.

This is because
the muscles have grown tired,

and let the warmer blood
from the core

stream back to the skin.

Blizzards can bring chaos
to vast swathes of land.

Power outages may occur

if lines are brought down
by fallen trees,

by the sheer weight
of ice and snow.

Water pipes freeze

and the supply of fuel
can be disrupted.

There have been many deadly
blizzards throughout the world.

In 1993,
a blizzard in the U.S.

dubbed "the storm
of the century"

killed over 200 people.

At its height,

the storm stretched
thousands of kilometers

from Honduras
in Central America,

all the way to Canada.

It resulted
in the loss of power

to over 10 million households.

The storm was so widespread

that it affected
an estimated 40 percent

of the American population.

Even worse, in terms
of the number of casualties,

was a blizzard
that struck Iran in 1972,

where 4000 lives were lost

when a shocking eight meters
of snow fell for over a week,

making it
the deadliest blizzard

to have occurred
anywhere in the world.

Two towns
were completely buried

with their entire
populations killed.

So how exactly does
a destructive blizzard form?

You need warm air moving in,

and you need cold air
moving in.

So specifically thinking about
the continental United States,

you need low-pressure areas,
you need high winds,

and you need cold mass of air
moving down south.

The low pressures
are right the way

across the Central Plains
of America.

They’re very common.

The supply of cold air?
From Canada principally.

I mean, the prairies,

but also maybe further north,
such as Greenland,

and of course,
even the Arctic.

The place that supplies
the cold air

is often
the Canadian prairies.

This flat, open region
doesn’t hold heat very well,

and is completely snow-covered
in winter.

It gets very little sun
during the short winter days,

and because
it’s so far north,

what little sunlight there is
comes in at a shallow angle

and has little heating effect.

The Rocky Mountains provide
a geographical feature

that also plays
an important role.

What happens
is if the jet stream

actually moves over an obstacle
like the Rockies,

there is a concept which we call
"conservation of vorticity."

And vorticity is essentially

a description
of how fast air rotates.

And so if air moves
over a mountain range,

or whatever obstacle,
it gets kind of squeezed.

And when you squeeze air,
it’s a bit like an ice skater,

air starts to swirl faster.

And if it does that,
it starts to bend,

and that bending happens in the
wake of the Rocky Mountains.

This bending is literally
an expression

of low-pressure activity.

So that is not only
what we call a trough,

which is like lower pressure

and more active weather
in general,

but it also provides
the conditions

for smaller
low-pressure systems.

And those that are associated
with blizzards to form.

Blizzards are usually
associated in people’s minds

with heavy,
fresh snowfall.

We’re getting off
a little bit early. Uh...

Trying to beat the storm,
expecting 2 feet. So, uh...

It’s a gorgeous day in New York.
No complaints.

That’s it.
Work hard, play hard.

But that is not the only way

that blizzards can occur.

In the Midwest
of the United States,

ground blizzards can strike,

and they require little
or no snowfall whatsoever.

Ground blizzards occur when
ferocious winds whip up snow

that is already on the ground.

Ground blizzards
pose such grave danger,

because they happen
immediately after

unseasonably warm air temperatures.

This can give people
a false sense of security.

Despite the fact that
there is snow on the ground,

they may leave home
without proper winter clothing.

But this strangely warm
weather may not last long.

If it is followed
by an Arctic cold front,

it can lead to a sudden drop
in temperature,

with winds gusting
up to 100 kilometers per hour.

Such strong winds will rapidly
stir up any snow on the ground

leading to whiteout conditions.

These blizzards are so lethal

because of the cold air
temperatures

that follow behind
the Arctic front.

Anyone stranded in a car,

or forced to walk outside,

is at risk
of serious frostbite,

hypothermia or even death.

In the United States,

the winter of 2009 to 2010

was defined by snowstorms
of historic proportions.

Millions of Americans
battled with unusual cold,

flooding, mudslides

and blizzards
on an astonishing scale.

That winter saw snow

in each of the 48 continental
United States.

Not even the Florida Panhandle
escaped the icy grip.

But how did the cold weather
manage to reach so far south?

So we have
like a large-scale setup,

which is associated
with the jet stream.

So this is really the waviness
of the jet stream itself.

And in those cases where this
waviness is very amplified...

So, what happens
is that the cold air

can then drag down
all the way to the U.S.,

and even Florida.

And that’s a really huge
reserve of cold air

which is just dragged
down south.

And at the boundary
between this cold air

and the warm air
to the south of the jet,

there’s a lot of potential
to form these smaller cyclones,

these smaller
low-pressure systems,

and that’s the ones that are
then associated with blizzards.

After the February storm,

snow blanketed 68 percent
of the nation.

It was the first time
many in the southern states

had ever seen snow.

The freezing cold extended
as far south as Miami,

which had only ever reported
snow once before, in 1977.

The winter season began with
a blizzard in the Midwest,

beginning on the 7th of December

and lasting three days.

That blizzard caused
the entire state of Iowa

to grind to a halt.

A second storm before Christmas

deposited up to half a meter
of snow on the east coast,

from North Carolina,
all the way up to Boston.

Then over
the Christmas holidays,

yet another snowstorm
spanned the Midwest,

from Texas to North Dakota.

December snowfall records
were set

in many American cities,
including Oklahoma City,

Philadelphia and Washington, D.C.

But the worst
was still to come.

Two blizzards
struck the mid-Atlantic,

back-to-back between
the 5th and 11th of February.

Rated a major
category three storm

on the Northeast Snow
Impact Scale,

"Snowmageddon,"
as it became known,

was the seventh worst blizzard
in U.S. history.

Before the winter
of 2009 and 2010,

you’d have been hard-pushed
to describe Washington, D.C.

as a particularly snowy place.

But all that was to change

when ferociously cold wind
and snow

took hold
of the nation’s capital.

The entire east coast
of America

braced itself for the worst
that winter could throw at it.

The extreme weather was
exceptionally well predicted.

People got ready to dig in
and stocked up on essentials,

though there were some
who waited too long

and found
their grocery stores empty.

So now imagine we can predict
a blizzard four days in advance,

as opposed to
two days in advance.

So really,
those extra two days,

which is two decades of weather
forecast improvement,

they really help.

Not only the people
at the ground

who have to plan
their holidays,

who have to plan
their businesses,

but also the policymakers,

the city managers,
to prepare.

For two days,

on the 5th and 6th
of February, 2010,

the capital was caught
in the vicious grip

of a ferocious blizzard.

High winds
and extraordinary snowfall

continued across the region

late on Friday evening
and Saturday.

It caused death and chaos,

with parts of the region

buried under half
a meter of snow.

Snowfall records were broken
at all three area airports,

with Dulles Airport
in Washington

setting an astonishing
single snowstorm record

of 82 centimeters.

At its brutal peak,

the federal government
was closed for almost a week.

And both Virginia and Maryland
declared a state of emergency.

Snow was falling
across a swathe

of the northeastern
United States,

from Southern Indiana,

eastward through Pennsylvania
to New York City,

and south
down the New Jersey coast,

through Delaware to Washington.

Authorities blamed the storm

for hundreds of accidents
and deaths.

Two hundred thousand people
were left without electricity

due to downed power lines.

Flights were canceled

at the Washington-Baltimore
area’s three main airports,

and at Philadelphia
International Airport,

where a reported
68 centimeters of snow

had fallen by 1 p.m.

Rail and bus services
were also suspended.

Delaware Governor Jack Markell
declared a state of emergency

and ordered all vehicles
off the roads by 10 p.m.

Because of the sheer quantity
of snow,

the clear-up after the storm
was an enormous challenge.

In addition to the normal
slow-going tasks

of clearing streets,
rails, runways

and pavements full of snow,

numerous trees and power lines
which had crashed to the ground

also had to be dealt with.

Power was out
for about 200,000 people,

and it would be five days
before it returned for many.

The sheer weight of snow

caused structural damage
to larger buildings.

A hangar
at Dulles Airport collapsed,

as did several churches and
fire stations across the area.

Anything with a flat roof

couldn’t stand up to the volume
of snow stacked on top of it.

The D.C. Metro system and train
services were also badly hit.

All area airports remained down
for up to three days.

There was an estimated
500,000 tons of snow to clear

in Virginia alone.

In some locations,

there was simply
nowhere left to put it.

In many areas,
special construction equipment

had to be brought in
to remove the snow.

But for a few,

the crippling snow

presented an opportunity
for winter sports.

Snowball fights cropped up
across parts of the city,

with perhaps
the largest being

a 2000-person melee
in Dupont Circle.

In an average winter,

Washington receives
about 40 centimeters of snow.

That amount fell
in less than 24 hours

on two separate occasions.

It took days
before some residents

were finally dug out
from the snowstorms.

And that blizzard
came less than two months

after the December storm

which had dumped
over 40 centimeters of snow

on the capital.

Snowfalls like that
were considered a rare event

in the D.C. area.

Now they had occurred
twice in one winter.

In fact, Washington, D.C.’s

final seasonal snowfall total
of 1.4 meters

beat the previous record,

which had stood since 1899.

But the winter was not over.

After a brief respite,

the chaos of early February

was followed later in the month
by a two-day snowstorm,

that was as powerful
as a hurricane.

This time, it was New York City
that bore the brunt.

The battering winds
and deep snow

forced schools
and public buildings to close,

and left more than
a million homes and businesses

without power.

The heavy snow forced
New York State Troopers

to close roads.

At JFK, LaGuardia
and Newark airports,

2300 flights were grounded

as airlines posted
major delays.

That winter, Baltimore’s old
record of 1.5 meters,

set in the winter
of 1995 to ’96,

was obliterated
after nearly 2 meters fell

over the 2009 to 2010 season.

Ronald Reagan National Airport
in Washington, D.C.,

beat the record snowfall that
had stood for over 120 years.

The 2010 Snowmageddon:
really extreme climate event,

really extreme blizzard.

You have this body of cold air
over Greenland,

which started to move south.

You’ve got the jet stream
bringing in warmer,

wetter weather
from the eastern Pacific.

And when these
air bodies collided,

then, of course,
you started getting

these severe
blizzard conditions.

But there was another
powerful contributor

to this terrifying blizzard:
El Niño.

El Niño is a regular feature,

which occurs semi-cyclically
in the Pacific,

where you have
unusually warm surface water

in the Pacific forming.

The warm water
will create a moist, warm air,

which will move across
the western United States.

And then it will start to get

sort of sucked
into the low-pressure system.

Because it contains
so much water,

it has the potential then,
as it cools,

to drop a lot of snow
on the U.S.

as it meets the colder air
coming down from the north.

Although blizzards
are frequent events

in mountainous regions,

they rarely strike cities

on the scale they did
during Snowmageddon.

That was supposed to be
a once-in-a-lifetime event.

But in January 2015,

it looked as if it was going
to happen all over again.

Computer models,
run by different agencies

in different countries,

were all saying
the same thing:

that the northeastern U.S.
was going to be in the grip

of a potentially
historic blizzard.

But unlike blizzards that’d
occurred a few decades ago,

which often struck
without warning,

this storm was forecast
seven days ahead of time.

Computer models have enormously
improved in recent years.

They’re fed by satellite data,
and radar data,

so that they feed into models,

and they give
very good patterns,

which then people can use
these patterns to predict

what is likely to happen
to the weather system.

These models are allowing
people to, early on,

try and make decisions about
what is likely to happen.

And of course, as a library
of knowledge has built up,

you have more confidence

in what you think the outcomes
are going to be,

of these emerging patterns
you see.

Every decade,
we can predict the weather

with one more day in advance.

This is an improvement which
really helps to save life.

And goes to show how important
this type of research is.

On the 20th to the 22nd
of January,

before the storm
had even occurred,

the governors of 11 states

and the mayor
of Washington, D.C.,

declared a state of emergency
in anticipation

of significant snowfall
and blizzard conditions.

But why was this blizzard
expected to be so bad?

So the meteorological
indicators are,

again,
sort of the emerging,

intensifying of the low pressure,

especially as the jet stream
gets sucked into that,

and the move of high pressure
further south,

maybe bringing in cold air
into the southern latitudes,

more southerly latitudes.

A swirling vortex

off the east coast sent
huge amounts of snow inland,

driven by sometimes
hurricane force winds,

pelting Washington, D.C.,
Philadelphia

and New York City with well
over half a meter of snow.

Based on satellite imagery,

the storm
was soaking up moisture

from as far south
as the Bahamas,

and as far east
as the Gulf Stream waters

of the Atlantic Ocean.

Up to 85 million people

were in the path
of this looming monster.

That meant that
one in every four Americans

were impacted by a blizzard
or winter storm warning.

Ten eastern U.S. states,
as well as Washington, D.C.,

all declared
a state of emergency.

This allowed them
to tap into the resources

they would need to cope
with the impending disaster.

In Washington,

Mayor Muriel Bowser
spared no words

in a warning to residents.

She insisted
that the oncoming storm

had life-and-death
implications,

and advised everyone
not to drive, or even walk,

but instead take shelter
and stay off the roads.

When it finally arrived,

the storm lived up
to expectations.

Tens of millions of people
from New York.

to the Appalachian Mountains
of Kentucky and West Virginia

were caught in a deadly mix
of devastating winds

and vast amounts
of falling snow.

Dewey Beach in Delaware

and Langley Air Force Base
in Virginia

recorded winds of over
120 kilometers per hour.

Even in Georgia,

a state where winters
are usually unremarkable,

there was snowfall
of over 15 centimeters.

There were 48 deaths
related to the storm,

and thousands of homes
were left without power.

But in low-lying areas
along the coast,

they didn’t just have to deal
with record-breaking snowfall.

The hurricane-force winds
caused storm surges

that sent water
rushing in from the sea.

The New Jersey
and Delaware shorelines

were pounded
with by 6-meter waves,

and a storm surge
of up to 1.5 meters

sent water levels to all-time
highs in some locations.

As floodwaters turned streets

on the Jersey Shore
into rivers,

residents were reminded
of the terrible days

of Hurricane Sandy in 2012.

There were record
coastal flood levels

recorded at both Cape May,

the city and seaside resort
in New Jersey,

and Lewes, on the opposite side
of the Delaware Bay.

All along the coast,
the sea was invading the land.

At Dewey Beach,

the hurricane-force winds
caused a surge

that washed huge swathes
of the shoreline out to sea.

Four and a half meters of beach
were gouged out by the storm.

Further inland,
many people perished

driving in the ferocious
conditions.

They were either caught out
by the storm

or had ignored the warnings
not to venture out.

In Pennsylvania,

a passing snowplow
buried a car

in which a man then apparently
died of asphyxiation.

Some people made the mistake

of continuing to run
their engines to keep warm,

even though their exhausts
were blocked by snow...

allowing poisonous fumes
to enter the car.

Not even
the emergency services

were safe
from the shocking conditions.

For three cities,

it was the biggest snowstorm
ever recorded.

Baltimore,
a major seaport in Maryland,

saw 74 centimeters
of fresh snow.

While in Pennsylvania,

Allentown had to deal
with 80 centimeters.

But the place that got
more snow than anywhere

was in Shepherdstown,

a town overlooking the Potomac
River in West Virginia,

which was buried
in well over a meter of snow.

It was also the first time

that a single storm
dumped more than 60 centimeters

on New York City.

New Yorkers who went to bed
on Friday

expecting to wake up
to few inches of snow,

drew their curtains
on a raging blizzard.

It forced Mayor Bill de Blasio

to order a travel ban
on city streets,

something that hardly ever happens,

meaning that anyone caught
driving would be arrested.

All public amenities
were ordered to shut.

Broadway theaters went dark.

Restaurants closed.

Shops shuttered.

A deathly hush descended

on the most populous city
in the United States.

Nearly 13,000 flights
were canceled.

At the height of the blizzard,

a quarter of a million people
were without power.

The storm looked
so vicious from space

that NASA astronaut
Scott Kelly tweeted pictures

from the International
Space Station.

Finally, after battering
the towns and cities

of the east coast,
the storm swirled out to sea,

leaving behind huge
accumulations of snow and ice

all the way from Virginia
in the south

up to New York in the north.

The Weather Service recorded
that 68 centimeters of snow

had blanketed Central Park
in New York City.

Sunday was a day
of transition.

The blizzard
with zero visibility

gave way to a bright,
clear sky.

For officials and residents

who had hunkered down
for two days

of unrelenting
snow and wind,

it was time
to start the cleanup.

And for others who’d been
cooped up indoors

for two days,

it was a chance to enjoy
the fun side of winter.

But a day of enjoyment
for many

gave way to the start
of the working week,

and the headache of commuting.

New York City,
where Mayor De Blasio

announced that schools
were to open,

faced the challenge of picking
up busloads of schoolchildren

in streets piled high
with snowdrifts.

In Washington, D.C.,
the Metro system,

for the most part,
was still shut.

Residents in some neighborhoods
in northwest D.C.

were effectively cut off

behind more than
half a meter of snow

on unplowed streets.

The leadership of
the House of Representatives,

scheduled to convene
on Monday,

said that no votes
would be held

in the week
following the blizzard.

In Maryland,

where two major highways
had been closed to all traffic,

Mayor Larry Hogan
announced that the state

would ask for federal
disaster relief aid

and warned
that clearing the snow

would be
a long-haul project.

In Baltimore,
the mayor cautioned

that she could not
give an end date

for when the streets
would be cleared.

But as with many of Mother
Nature’s deadly disasters,

there is often a benign side
to extreme weather events.

The snow provides
much-needed water.

During the winter of 2018,

blizzards and half a meter
of snow hit Moscow,

and was welcomed
by agricultural experts.

That’s because
a heavy blanket of snow

is beneficial
for wheat crops.

It protects
the developing plant

from the harsh cold
of winter.

The extent
to which snow insulates

depends on its depth.

Temperatures underneath
a layer of snow

increase by
about 1 degree Celsius

for each 2.5 centimeters depth
of snow.

Because the soil
also gives off some heat,

the temperature
at the soil surface

can be much warmer
than the air temperature.

When growth of the wheat plants
restarts in spring,

the melting snow
is also a good source of water.

The end of winter

doesn’t necessarily
signal the end

of extreme
cold weather phenomena.

The early summer of 2013

brought extreme weather
to Europe.

In June,
there were floods,

followed by a heat wave,

as Central Europe experienced
soaring temperatures.

In late July,

thermometers in the German city
of Rheinfelden

peaked at 38.6 degrees Celsius.

But, bizarrely,

the extreme heat
brought with it

a swathe of destruction
caused by hailstones,

and on an unprecedented scale.

Ice balls cannoned down
on an area of central Germany.

These monster hailstones

measured in
at up to 12 centimeters.

They caused 2.8 billion euros’
worth of damage.

The most devastating hailstone
event in Germany’s history,

and the world’s biggest
insurance loss of 2013.

So how does ice do that much
damage in the summer months?

In fact,
how does the ice form at all?

On a hot summer’s day,

the ground will be warmed
by the sun,

and any moisture will evaporate
into the air above it.

This air will be warm.

And so as it rises
into the cooler atmosphere,

the moisture will condense
and form clouds,

creating thunderstorms.

We’ve all seen these huge,
towering cumulonimbus clouds,

10 to 15 kilometers high.

And they have a huge updraft.

These updrafts
suck water droplets

through the freezing zone.

At this point, the water
droplet starts to supercool.

And then to become ice,
and then start to accrete more,

and more ice to it.

They sort of grow
a bit like an onion,

in layers,

and eventually,
once it becomes so heavy

that the updraft
can no longer support it,

it then comes crashing down
to Earth.

Some hailstones
can be very heavy.

They can be moving
at very high speeds,

over 170 kilometers per hour
when they impact the Earth.

Hailstones are measured
according to their diameter.

But it is easier
to estimate its size

by comparing it
to everyday items.

To date, the largest hailstone
recorded in the U.S.

fell in Vivian, South Dakota
on the 23rd of July, 2010.

The largest hailstone
recorded in the U.S.

was 20 centimeters in diameter,

weighing about
sort of 900 grams.

So you know,
quite a sizable chunk of ice.

That’s an officially recorded
hailstone of that size.

And if that
doesn’t terrify you,

then imagine it hitting
the ground

at 170 kilometers per hour.

The heaviest hailstone
ever measured

is thought to be one
in Bangladesh,

over a kilogram in weight.

It occurred during a hailstorm
in 1986, I think it was.

And that hailstorm actually
killed over 90 people.

Luckily,

the hailstones
that fell on Germany

were not of
those proportions,

and although they caused
a huge amount of damage,

thankfully,
no one was killed.

But Germany is no stranger
to extreme winter weather,

each and every year
people are killed in blizzards,

usually in the German Alps.

On Sunday,
the 13th of July, 2008,

a summer blizzard caused
tragedy in the Bavarian Alps,

where 550 people taking part
in a mountain run

were caught out
by a freak blizzard.

Competitors were running up
the slopes of the Zugspitze,

Germany’s highest peak.

Many were dressed
only in shorts and T-shirts

when the temperature suddenly
plummeted to below freezing.

With winds gusting
at 80 kilometers per hour,

the windchill and low
visibility from driving snow

had turned a picturesque
mountain into a disaster zone.

The first distress call

reached mountain rescue
in the valley bellow

just before midday.

But for two men,
help arrived too late.

They sadly died,

while a further six people
were taken to hospital.

But it isn’t only
in Germany’s mountains

that blizzards can kill.

On the 16th and 17th
of December, 2010,

much of Germany was paralyzed
in the grip of a winter storm

that claimed the lives
of three people,

caused hundreds of accidents,

and left thousands stranded
in perilous conditions.

A colossal winter storm system

came in hard and fast,

catching many people
by surprise.

As temperatures
were sent plummeting

to minus-12 degrees Celsius,

30 centimeters of snow
fell in a matter of hours,

bringing chaos
not usually seen

in that part of the world.

Frankfurt Airport,
Europe’s second largest hub,

was forced to close
while emergency services

battled to clear
its snowbound runways.

One thousand passengers
were stranded

in the terminal
building overnight.

There was chaos for drivers,

with most of Germany’s road
network in gridlock.

At the German-French border
near Freiburg,

hundreds of lorries
were stuck for hours,

when French authorities

closed the motorways
due to heavy snow.

The Red Cross
handed out blankets

and hot soup to the drivers.

In North Rhine-Westphalia,
Germany’s most populous state,

traffic congestion extended
for more than 185 kilometers.

Two hundred and fifty-one
accidents occurred

as a result
of the winter storm,

injuring 19 people.

But, seven years later,

it wasn’t only Germany that
felt the icy blast of winter.

It was the entire continent
of Europe.

Winds which became known
as "The Beast from the East"

transported freezing
temperatures and blizzards

from Russia into Germany,

France and the U.K.

It was warmer in the North Pole
than it was in much of Europe,

as both the north Pacific
and north Atlantic Oceans

fed milder air into the Arctic.

In February 2018,

the so-called "Beast
from the East" hit Europe.

And what did happen in that case
is that in mid-February,

a really cold air reserve
started to form in Siberia,

which isn’t uncommon
for that time of the year.

And then, opposite to what
you would usually expect,

when the circulation

essentially pushes the air
from west to east,

in that case, the cold air
slowly moved to the west,

and started to impact Europe
more and more.

And ended up as a pretty severe
late winter cold event,

which hit
almost all of Europe.

The physics of what causes
these sorts of storms

is that you have what’s called
a polar vortex,

which is a vortex of--
Of low pressure,

which is sitting
over the Arctic.

In a sense, sort of containing
the cold air.

But as that vortex weakens,
it will split.

It can split into two,
quite typically.

One over Greenland and Canada.

One over Siberia.

And, actually,
if the vortex weakens further,

it will split into even more.

And, actually,
that will start to push

the jet stream
further south.

And actually then,
the cold air

will move down
into lower latitudes.

So this is what was happening
with the "Beast from the East,"

and at the same time,
you’re having--

For the United Kingdom
and Europe.

you’re having a warmer air
moving in from the southwest,

meeting this colder air coming,
as this polar vortex weakened.

And you have these cold fronts

moving in
from continental Europe.

Much of Europe
was blanketed in snow,

as icy conditions
spread as far south

as the Mediterranean coast,

carrying freezing winds
and accompanying blizzards

across the continent.

Temperatures plummeted as low
as minus-30 degrees Celsius.

Many in the Netherlands

referred to the uncommonly
cold weather

as the "Siberian Bear."

Not even countries

in the normally mild
south of the continent

were spared
blizzard conditions.

The monster freeze

brought unheard-of snowfalls
to parts of Spain,

as well as the Mediterranean
islands of Corsica and Capri.

In Rome’s St. Peter’s Square,

priests and seminarians
from the Vatican

threw snowballs
at each other.

And near the Colosseum,

students could be seen skiing
down the historic Oppian Hill.

Snowfall covered
the northern Italian cities

of Venice, Milan,

Turin and Florence,

and reached as far south
as Naples.

In Ireland and Scotland,

the highest red weather
warning alerts

of "a risk to life"
were issued,

and people were told
to stay at home.

Up to 40 centimeters
of snow fell

in higher areas
of Scotland,

and hundreds of vehicles

were stuck on a Scottish
road overnight,

stranding some motorists
for 18 hours.

England experienced blizzards

and some of the coldest
temperatures for three decades.

Hundreds of schools
were closed,

and there were delays
on roads, railways,

and at airports.

Even Switzerland, a country
well used to blizzards,

was taken aback
by the sheer volume of snow

and the freezing temperatures.

The airport in Geneva
was forced to close.

Temperatures dropped
to minus-20 degrees Celsius

in some parts of Germany,

while the Zugspitze,
the country’s highest peak,

was gripped
in a record-breaking low

of minus-30.4 degrees Celsius.

In the Black Forest region
of southern Germany,

the 97-meter-high Todtnau
Waterfall was frozen solid.

In the end, the most important
part of risk

is actually not the hazard.

And I think that we are
addressing vulnerability

in two ways:
on the one hand,

we can be far better informed
and forewarned

about blizzards
through the increase of science,

satellite observation
radar.

But also, I think, you know,
the understanding

of the importance
of vulnerability

means that we’re looking
at how we build social capital.

Who are the vulnerable people,

and how can we help
in extreme events?

Many people ask,

"What’s the role
of climate change?"

So do, like, these winter storms

become even more frequent
in the future?

Which is counterintuitive, right?

So there are a couple
of suggestions and discussions

in the research community
that do, indeed,

link to an increased frequency
of these kind of storms,

especially, like, snowstorms.

And there’s a couple reasons
for that.

First of all,
if you do have a snowstorm

in a warmed-up world--

A world that is 1, 2
or 3 degrees warmer.

you tend to have
more moisture supply.

It doesn’t matter
whether it is winter or summer,

whether there is super frozen
water in the high atmosphere,

or winds
and freezing temperatures

at the ground level.

Blizzards can occur
in any number of scenarios.

Mother Nature
has proven to us yet again

the chilling
and unexpected ways

she can twist the elements
to bring us...

Deadly Disasters.