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*
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After decades of lying dormant,
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a volcano explodes.
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Superheated rock and ash thunder
downhill with irresistible force.
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00:00:27,600 --> 00:00:32,960
This is what happens when powerful
forces deep within the Earth erupt.
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New land rises
out of the Pacific Ocean.
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The Earth's violent interior
pushes into the sea.
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This is where lava meets the ocean
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in one of the most spectacular shows
on Earth.
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This is where scientists come to
witness
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the power of the planet firsthand.
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Geologist Ken Hon monitors landscapes
in the making.
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This region is one of the few places
in the world
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where you can see the world change
before your eyes.
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Couple of months ago, the land
behind me wasn't here.
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None of it was here, it was just
a sea cliff into the ocean.
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It really is truly dynamic.
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Hawaii's Kilauea is the most active
volcano on Earth.
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It's created by a hot spot
of molten magma
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that lies 65km below the surface.
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Here, heat is constantly released
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and rivers of molten rock turn
seawater to steam.
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It's not like steam
you have in your kitchen.
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It's coming in contact with lava
that's close to 2,000F
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so the steam gets superheated.
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So it's very, very explosive.
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Ken is compiling a video log of
Hawaii's changing coastline.
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To capture every detail
of the action,
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he uses slow motion photography.
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What we film out here,
most of the time,
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just helps us see things that we
can't see with our own eyes.
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Hawaii grows out into the Pacific
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at a rate of seven and a half
hectares a year.
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The volcanoes here are highly active
but not often deadly.
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This is unusual.
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Most volcanoes in the world can be
much more dangerous.
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Volcanoes that erupt regularly
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are less deadly than those that lie
quiet for centuries,
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building up pressure inside.
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When dormant volcanoes explode, they
can also unleash tsunamis,
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mudflows, avalanches of burning rock
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and superheated ash clouds.
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Throughout history,
these explosive eruptions
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have claimed countless lives.
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Kilauea has been spewing out
superheated molten rock
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for the past 26 years
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but few people have been killed.
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This kind of lava is largely made up
of basalt
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which hardens to a black crust.
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Since 1983, new lava has covered over
100km square.
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By 2008,
Jack Thompson was the only one left
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in the town of Royal Garden.
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Oh, it was all just pristine forest.
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It was green
all the way to the ocean.
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It was just a wonderland.
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1983, the lava started
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and I got up one morning and looked
over the back of the mountain
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and you could see a glow.
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That's kind of a shock
ruining all your scenery,
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all the sudden changes
for something totally different.
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Luckily,
the lava advanced slowly enough
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for people to get out of the way.
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Nearly 200 homes were destroyed.
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Park ranger Jay Robinson witnessed
the destruction
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that's still going on today.
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We've had over 200 homes
and structures now destroyed
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in this eruption
we're having right now.
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But no-one died
because you just walk away.
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The lava only flows as fast
as a baby crawls in most cases.
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Because Kilauea's flanks
are gently sloping,
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the lava spreads out sideways,
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cools quickly and slows down.
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So Kilauea's lava may look dangerous
but it rarely kills anyone.
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But when cities sit
on steep volcanic slopes,
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eruptions can pose a serious threat.
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Those who live on this volcano
need to know
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whether the lava will cool quickly
and stop
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or remain hot and keep on flowing.
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Southern Italy is a region
threatened by many volcanoes.
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On the island of Sicily,
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Mount Etna is the biggest and most
active volcano in Europe.
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Etna has erupted four times
since the year 2000.
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When it blows, the lava flows destroy
everything in their path.
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The lava flows usually remain on
the volcano's higher slopes.
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But not always.
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Sometimes, larger eruptions invade
towns lower down the mountain.
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Over the past 300 years,
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16 villages have been destroyed.
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In this highly populated region,
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the pressure is on to work out what
Mount Etna will do next.
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*
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*
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Europe's biggest volcano, Mount
Etna, looms over a million people.
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Dr Clive Oppenheimer
is a volcanologist
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In this tunnel below Mount Etna,
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he's learning how the volcano's lava
has behaved in the past.
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What we're looking at is the
solidified wall of a lava tunnel.
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This was formed 400 years ago and
you can get an impression
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of just how this lava was,
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so fluid that
it dribbled off the roof.
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You can see here
a little droplet of lava
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and this tells us the lava was very,
very hot,
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very fluid and runny.
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If lava is insulated by a tunnel,
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it remains hot, fluid
and extremely dangerous.
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Instead of flowing
maybe five miles down Etna,
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it flows ten, 15 miles down
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and reaches some of the towns
on the flanks.
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Clive wants to know if there are
any lava flows
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hidden below the flanks of
the volcano right now.
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He uses a thermal imaging camera
to detect them.
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He discovers the upper slopes
are riddled with lava flows
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and at over 2,000 degrees,
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they're fluid enough to run down the
mountain.
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These constant eruptions release
pressure
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from the magma chamber below Etna.
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But it's the volcanoes that don't
blow regularly
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that build up pressure which prove
most dangerous.
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Rising above the densely populated
city of Naples,
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this is one of the most dangerous
volcanoes in the world.
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When Vesuvius erupted
1,400 years ago,
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it buried the town of Pompeii in ash
and claimed 2,000 lives.
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00:12:59,400 --> 00:13:02,320
In 1944, during World War Two,
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the US Army faced an unexpected
adversary - Vesuvius.
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An eruption killed 26 people.
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Vesuvius is quiet now,
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building up for the next big one.
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But Dr Clive Oppenheimer is
interested
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in the island volcano of Stromboli
nearly 300km away
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which is constantly exploding.
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It might look a relatively small
volcano.
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It goes about three quarters of a
mile above sea level
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but below the sea, there's another
one and a half miles of this volcano
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so it's really massive.
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00:14:00,800 --> 00:14:04,000
At the foot of the volcano is the
village of Stromboli.
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80km beneath it,
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one of the Earth's tectonic plates is
sliding under another,
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generating a series of continuous
explosions.
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00:14:21,800 --> 00:14:26,960
No other volcano on Earth is known to
erupt so often and so consistently.
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00:14:35,400 --> 00:14:38,040
Clive Oppenheimer studies volcanic
gases
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to better predict eruptions.
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Here on Stromboli, he has a constant
source from the magma beneath.
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So one of the things I'm really
interested in
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is how the gas escapes from magma
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and I think we can even hear it
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as this vent on the volcano is
breathing.
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It's the volcano's puffing.
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(PUFFING WIND)
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If magma is the fuel of volcanoes,
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the trigger for these eruptions is
the gas that's contained in it
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and that gas, as it comes up to the
surface,
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it expands really violently
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and then it blows the chunks of
bubble skin,
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magma bubbles flying into the air.
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Like a champagne bottle,
Stromboli is full of gases.
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So when it's uncorked,
the gases escape
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and propel showers of lava
into the air.
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When we see this kind of activity
going on,
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it's impossible for me to imagine
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how we could actually control
volcanoes.
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But we CAN try and understand how
volcanoes work
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and use that information to predict
eruptions.
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Clive uses a spectrometer to analyse
the volcanic gases.
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They tell him how deep within the
Earth
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the explosive bubbles are formed.
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Look at that. That is fantastic.
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I think the vent there has got
really choked
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so when the magma's trying to get
through,
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it's blasting out all the rocks that
have choked the vent up
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and pulverising the rocks into ash.
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There's a beautiful ash cloud coming
up here
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and I think it's drifting right
towards me.
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It's raining ash.
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A moment ago it was 2,000 degrees in
the vent of that volcano
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and now it's a cooled down little
piece of ash
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seconds later in my hand
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and that rock was just made just
now.
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That's quite an amazing thing, really.
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Ooh...
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There again, another instantaneous
explosion.
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You can't help to feel something
emotionally
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when your whole body is vibrating
with the shock wave.
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But actually, this is small fry in
the deadly arsenal
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of active volcanoes on planet Earth.
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Stromboli's bark is worse than its
bite.
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Many of the world's other volcanoes
are much more dangerous.
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*
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*
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When hundreds of years of built-up
pressure blasts out of the Earth,
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it completely changes the landscape.
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Here, in the cascade range of the
Pacific North-west,
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many of the mountains are sleeping
volcanoes.
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When one finally blew,
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it produced one of the biggest
volcanic eruptions in living memory.
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In 1980, Mount St Helens had been
dormant for over 120 years.
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So when swarms of earthquakes shook
the mountain
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and a small crater formed at its
summit,
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scientists from the US Geological
Survey noticed straightaway.
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Richard White was one of them.
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00:19:08,360 --> 00:19:10,800
There is a certain fatalism amongst
geologists
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that have worked around these
volcanoes
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'cause we all know that if you're
gonna work around one
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that's getting ready to erupt,
there's some risk.
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Richard's colleague, David Johnston,
was also on the mountain.
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David Johnston was up on this ridge,
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just a quarter miles from where we
are now
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and he was monitoring Mount St
Helens in an official capacity.
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David had parked his trailer in front
of the volcano's north flank
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to keep an eye on an ominous bulge.
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00:19:42,800 --> 00:19:46,040
That same day, amateur photographer
Keith Ronnholm
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made his way to a scenic spot
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00:19:48,040 --> 00:19:51,280
also overlooking the volcano's north
flank.
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00:19:53,000 --> 00:19:57,080
Bear Meadow, where I was 28 years
ago in 1980,
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I was ten miles from the mountain.
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It seemed like a perfectly safe
place to be.
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But just after 8.30 that morning,
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the last of a series of earthquakes
hit,
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triggering one of the largest
landslides in recorded history.
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I glanced over at the mountain and
the entire north face
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was in motion, was sliding down
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and it's such an unbelievable view
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that I shook my head and I said,
'Am I really seeing this?'
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I dove for my camera and stood there
and started taking pictures
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and the very first picture
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shows that the entire side of the
mountain blowing out.
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It was quiet, there was no sound
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00:21:04,480 --> 00:21:07,000
so there was no big explosion, noise
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00:21:07,000 --> 00:21:09,520
or anything that would make you want
to run.
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00:21:15,600 --> 00:21:20,000
The landslide had released highly
pressurised volcanic gases.
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But instead of shooting upward,
they blew out sideways.
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The blast roared across the landscape
at nearly 500km per hour
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00:21:34,120 --> 00:21:37,160
and hit geologist David Johnston's
trailer.
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00:21:52,800 --> 00:21:58,440
12km away, Keith Ronnholm was still
taking these pictures.
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00:21:58,440 --> 00:22:01,320
In one of the pictures, you can see
projectiles
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00:22:01,320 --> 00:22:04,000
being ejected out with, like, trails
behind them
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and those are like house-sized
objects.
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You could see it coming towards me
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and then it hit the most distant
ridge out there.
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00:22:14,280 --> 00:22:18,200
It began to break over like a wave
breaks over a breakwater
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00:22:18,200 --> 00:22:20,120
and curl over and churn.
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00:22:20,120 --> 00:22:23,160
You just want to watch it but on the
other hand, it's getting closer
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00:22:23,160 --> 00:22:28,280
and so there's a conflict of,
do I stay and watch or do I go?
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Keith Ronnholm was lucky.
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00:22:36,840 --> 00:22:40,080
The blast tore past to the west of
him.
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But fisherman Danny Balch had set up
camp beside a river
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and was directly in its path.
247
00:22:47,760 --> 00:22:50,520
It was a beautiful setting,
248
00:22:50,520 --> 00:22:54,120
the birds and animals were totally
quiet.
249
00:22:54,120 --> 00:22:57,360
It was so dead quiet.
250
00:22:57,360 --> 00:23:02,000
Danny Balch was 25km away and
couldn't see the mountain.
251
00:23:03,520 --> 00:23:07,280
He knew nothing of the explosion
until it thundered towards him.
252
00:23:07,280 --> 00:23:09,360
As it went over the top of our
heads,
253
00:23:09,360 --> 00:23:12,040
it was pitch-black and you could see
nothing.
254
00:23:12,040 --> 00:23:15,760
A couple of seconds later, then it
started hitting us.
255
00:23:18,400 --> 00:23:20,520
Started knocking all the trees down.
256
00:23:20,520 --> 00:23:22,920
I was pressed to the ground like a
pancake,
257
00:23:22,920 --> 00:23:25,560
all the air pressed out of me and
everything
258
00:23:25,560 --> 00:23:28,920
but I was also at that point
starting to feel burnt.
259
00:23:34,800 --> 00:23:37,600
This was just like a snap of the
fingers, it was that fast,
260
00:23:37,600 --> 00:23:39,400
and I believe that if we would have
been
261
00:23:39,400 --> 00:23:41,280
in an eruption that would last
longer,
262
00:23:41,280 --> 00:23:43,920
we would have baked, we'd have been
dead for sure.
263
00:23:48,000 --> 00:23:51,240
Danny Balch was just far enough away
from the explosion
264
00:23:51,240 --> 00:23:53,800
to survive with third-degree burns.
265
00:23:55,800 --> 00:23:58,240
57 others weren't so lucky.
266
00:24:02,400 --> 00:24:05,480
When geologist Richard White flew
over the landscape,
267
00:24:05,480 --> 00:24:08,200
everything within sight had been
obliterated.
268
00:24:11,600 --> 00:24:16,520
And nearly 400km square of forest
flattened by the blast.
269
00:24:23,800 --> 00:24:27,120
Richard's colleague, David Johnston,
had been killed.
270
00:24:29,200 --> 00:24:31,720
We never found any trace of him, really.
271
00:24:31,720 --> 00:24:34,080
The camp was over there
272
00:24:34,080 --> 00:24:37,960
and there was a camp trailer,
aluminium camp trailer.
273
00:24:37,960 --> 00:24:42,080
Pieces of it were much later found
scattered down slope.
274
00:24:43,600 --> 00:24:47,000
We found cups and stuff out of it,
just some debris out of the trailer.
275
00:24:47,000 --> 00:24:49,360
Bits of aluminium from the trailer
and so on.
276
00:24:49,360 --> 00:24:51,400
So the trailer itself got shredded.
277
00:24:54,200 --> 00:24:56,720
It happened to be David Johnston
over here on May 18th
278
00:24:56,720 --> 00:24:58,360
but it could have been any of us.
279
00:25:01,600 --> 00:25:06,280
The eruption of Mount St Helens was
150 times more powerful
280
00:25:06,280 --> 00:25:08,360
than the Hiroshima atomic bomb.
281
00:25:11,400 --> 00:25:14,720
It turned great sways of Washington
State Forest
282
00:25:14,720 --> 00:25:17,320
into something more like the moon.
283
00:25:21,600 --> 00:25:23,560
But in some parts of the world,
284
00:25:23,560 --> 00:25:27,120
devastating explosions happen all the
time.
285
00:25:45,400 --> 00:25:49,240
Big volcanic blasts are exterminators
286
00:25:49,240 --> 00:25:53,480
but volcanoes have more than one way
to kill.
287
00:25:53,480 --> 00:25:59,000
In 1995, a volcano erupted on the
Carribbean island of Montserrat.
288
00:26:03,400 --> 00:26:06,400
The blast created a pyroclastic flow,
289
00:26:06,400 --> 00:26:10,360
a speeding avalanche of hot rock,
dust and gas.
290
00:26:15,400 --> 00:26:19,280
These deadly surges charged down the
slopes of a volcano
291
00:26:19,280 --> 00:26:21,240
and across the landscape.
292
00:26:23,000 --> 00:26:25,600
At temperatures of more than 800
degrees,
293
00:26:25,600 --> 00:26:29,440
they race over water on a layer of
superheated steam.
294
00:26:36,800 --> 00:26:38,960
Japan, 1991.
295
00:26:41,200 --> 00:26:44,400
After lying dormant for almost 200
years,
296
00:26:44,400 --> 00:26:47,680
the volcano Mount Unzun roared into
life.
297
00:26:52,000 --> 00:26:55,880
The eruption attracted the attention
of scientists and press.
298
00:26:57,800 --> 00:26:59,960
But one group made a fatal mistake
299
00:26:59,960 --> 00:27:02,120
when they went into the exclusion
zone
300
00:27:02,120 --> 00:27:06,200
and got caught in the path of a
pyroclastic flow.
301
00:27:24,000 --> 00:27:28,840
43 people died as superheated gases
burned their lungs.
302
00:27:40,400 --> 00:27:44,360
Mount Unzun is one of more than a
thousand active volcanoes
303
00:27:44,360 --> 00:27:46,960
that circle the Pacific Ocean.
304
00:27:46,960 --> 00:27:49,880
This chain is called The Ring Of
Fire.
305
00:27:52,000 --> 00:27:54,800
The volcanoes occur above subduction
zones
306
00:27:54,800 --> 00:27:59,960
where submerged oceanic plates dive
under continental land masses.
307
00:28:03,400 --> 00:28:07,440
The most dangerous section of this
volatile chain is Indonesia.
308
00:28:11,000 --> 00:28:14,000
There are 130 active volcanoes here,
309
00:28:14,000 --> 00:28:16,200
more than any other country on Earth.
310
00:28:18,000 --> 00:28:21,320
Some are less dangerous because they
release pressure constantly.
311
00:28:24,600 --> 00:28:28,200
But others have produced the biggest
explosions ever known.
312
00:28:33,200 --> 00:28:39,120
Out in the Sunda Strait, 72km west of
Java, lies Anak Krakatau.
313
00:28:41,000 --> 00:28:46,400
In 1883, this volcano's parent
Krakatoa exploded with a force
314
00:28:46,400 --> 00:28:49,760
equivalent to more than a thousand
atomic bombs.
315
00:28:51,280 --> 00:28:54,160
It made the loudest bang in recorded
history.
316
00:28:56,200 --> 00:28:59,960
It blasted almost the entire island
out of existence.
317
00:29:01,600 --> 00:29:06,400
Tsunamis over 30m tall flooded the
coast of Java and Sumatra
318
00:29:06,400 --> 00:29:09,040
up to 65km away.
319
00:29:12,000 --> 00:29:16,000
Krakatoa claimed at least 36,000
lives.
320
00:29:23,400 --> 00:29:26,400
In the 1920s, geologists watched
321
00:29:26,400 --> 00:29:30,720
as a new volcano Anak Krakatao, the
child of Krakatoa,
322
00:29:30,720 --> 00:29:32,360
rose out of the sea.
323
00:29:49,200 --> 00:29:54,520
By the 1980s, this island had grown
to over 200m above sea level.
324
00:29:56,800 --> 00:29:59,320
But the volcano did not stop there.
325
00:30:05,600 --> 00:30:10,520
Geologist Mike Ramsey has come to
Indonesia to study Anak Krakatau,
326
00:30:10,520 --> 00:30:14,120
which today is one of the world's
most violent volcanoes.
327
00:30:14,120 --> 00:30:18,760
I would like to see how the
volcano's changed in the eight years
328
00:30:18,760 --> 00:30:20,440
since I've last been here.
329
00:30:20,440 --> 00:30:23,880
I know that it's had a lot of
activity, a lot of change.
330
00:30:23,880 --> 00:30:28,600
The bay Ramsey is crossing is where
the original Krakatoa once stood.
331
00:30:30,400 --> 00:30:34,560
Back in 1883, everything you see
behind me was part of one island...
332
00:30:36,080 --> 00:30:41,240
...and when you can eject this much
rock and magma and water and land,
333
00:30:41,240 --> 00:30:43,360
the forces are enormous.
334
00:30:45,400 --> 00:30:49,680
And smack in the middle of this
crater is the current active volcano
335
00:30:49,680 --> 00:30:52,880
Anak Krakatau and that's the current
hot spot
336
00:30:52,880 --> 00:30:55,960
and the current active craters are
still very dangerous.
337
00:31:03,000 --> 00:31:07,760
The new volcano, Anak Krakatau, has
grown over 300m
338
00:31:07,760 --> 00:31:09,640
in less than a hundred years.
339
00:31:12,000 --> 00:31:16,080
From the summit, the extent of the
original volcano becomes clear.
340
00:31:18,200 --> 00:31:21,560
These outer islands are all that's
left of the old Krakatoa
341
00:31:21,560 --> 00:31:24,800
that once filled this 8km-wide bay.
342
00:31:28,400 --> 00:31:31,800
Geologist Mike Ramsey retreats to a
safe distance
343
00:31:31,800 --> 00:31:35,200
to take further measurements of the
activity in the new cone.
344
00:31:46,000 --> 00:31:50,560
Right now, Krakatau's erupting a
small Strombolian style eruption.
345
00:31:50,560 --> 00:31:53,280
It's basically putting up ash column
346
00:31:53,280 --> 00:31:56,000
somewhere between half a mile and a
mile high.
347
00:31:58,200 --> 00:32:01,280
The island will continue to grow,
continue to get larger.
348
00:32:01,280 --> 00:32:04,080
At some point, maybe in a hundred
years or more,
349
00:32:04,080 --> 00:32:07,800
there might be another larger
eruption like there was in 1883.
350
00:32:11,800 --> 00:32:14,840
Monster eruptions like Krakatoa are
rare.
351
00:32:16,400 --> 00:32:17,920
But they still occur.
352
00:32:19,600 --> 00:32:24,040
In 1991, another giant eruption along
The Ring Of Fire
353
00:32:24,040 --> 00:32:27,960
threatened 60,000 people in the
Philippines.
354
00:32:35,920 --> 00:32:40,000
*
355
00:32:43,000 --> 00:32:45,000
*
356
00:32:45,000 --> 00:32:49,880
Mount Pinatubo in the Philippines
had been dormant for 600 years.
357
00:32:49,880 --> 00:32:53,000
Even when it started rumbling in
1991,
358
00:32:53,000 --> 00:32:56,120
few had any idea how dangerous it
was.
359
00:32:58,200 --> 00:33:02,400
Geologist Andy Lockhart was part of
the team sent in to observe.
360
00:33:04,400 --> 00:33:07,200
Pinatubo just didn't look like a
volcano
361
00:33:07,200 --> 00:33:09,880
to anybody who wasn't a geologist.
362
00:33:09,880 --> 00:33:13,360
Now, as a geologist, you'd look at
it and say,
363
00:33:13,360 --> 00:33:15,040
'That's a very bad volcano'
364
00:33:15,040 --> 00:33:18,320
because this volcano, when it
erupts,
365
00:33:18,320 --> 00:33:22,080
this one just blows itself apart so
this is not a good place to be.
366
00:33:24,600 --> 00:33:28,400
Clark Airforce Base was situated at
the foot of the volcano.
367
00:33:30,400 --> 00:33:34,960
It was home to 20,000 US military
personnel and their families.
368
00:33:36,480 --> 00:33:38,800
Sergeant Maree Rogers
was one of them.
369
00:33:38,800 --> 00:33:41,800
The volcanologist was saying that
this was death underground
370
00:33:41,800 --> 00:33:43,640
that nobody would want to mess with.
371
00:33:45,440 --> 00:33:48,160
When the airbase was evacuated on
June 11,
372
00:33:48,160 --> 00:33:52,560
Rogers and Lockhart was part of
the skeleton crew left behind.
373
00:33:57,600 --> 00:34:00,960
One day later, Pinatubo blew its top.
374
00:34:04,600 --> 00:34:08,840
But this explosion was minor compared
to what followed three days later.
375
00:34:11,800 --> 00:34:15,840
I went outside the hangar and turned
around and looked
376
00:34:15,840 --> 00:34:20,680
and all of a sudden it looked like,
I guess you would describe it as
377
00:34:20,680 --> 00:34:24,440
the mountain range exploding from
left and right.
378
00:34:26,800 --> 00:34:30,480
This was the second biggest eruption
of the 20th century.
379
00:34:33,200 --> 00:34:36,600
When a column goes up like that and
it hits the stratosphere,
380
00:34:36,600 --> 00:34:38,800
and you get this nuclear cloud
thing,
381
00:34:38,800 --> 00:34:42,560
when you get the mushroom cloud, it
spreads out on the stratosphere.
382
00:34:44,600 --> 00:34:47,120
The ash cloud turned day into night.
383
00:34:48,640 --> 00:34:51,760
All it was, just dark, dark, dead
dark, dead,
384
00:34:51,760 --> 00:34:55,480
hard storm in the middle of the
night, 'no lights at all' dark.
385
00:34:57,600 --> 00:34:59,680
It's a feeling you can't really
describe
386
00:34:59,680 --> 00:35:03,600
when the sun you can't see, you know
you're supposed to have sunlight
387
00:35:03,600 --> 00:35:05,400
and everything is dark.
388
00:35:05,400 --> 00:35:08,360
And yet, you're getting all this mud
and stuff on you.
389
00:35:08,360 --> 00:35:10,800
I thought that, this is it.
390
00:35:10,800 --> 00:35:12,920
This is it, this is the big one.
391
00:35:16,200 --> 00:35:19,960
At midday, it was more like midnight
for miles around.
392
00:35:26,800 --> 00:35:29,040
Ash clouds from volcanic explosions
393
00:35:29,040 --> 00:35:31,760
can completely block out
all daylight.
394
00:35:38,600 --> 00:35:40,520
But these terrifying phenomena
395
00:35:40,520 --> 00:35:44,000
can have far-reaching
and more damaging effects.
396
00:35:46,200 --> 00:35:49,680
The ash from the cataclysmic eruption
of Mount Pinatubo
397
00:35:49,680 --> 00:35:53,080
shot more than 30km
into the stratosphere.
398
00:35:57,600 --> 00:36:00,400
In less than a month, it circled the
globe.
399
00:36:02,600 --> 00:36:07,320
Eventually, ash particles drifted
across the entire planet
400
00:36:07,320 --> 00:36:10,560
and reflected so much sunlight back
into space
401
00:36:10,560 --> 00:36:14,440
that it lowered global temperatures
for at least two years.
402
00:36:21,400 --> 00:36:27,120
In the Philippines, millions of
tonnes of ash covered 700km square.
403
00:36:31,600 --> 00:36:35,280
In some places, it was 180m deep.
404
00:36:40,200 --> 00:36:43,080
Everything was grey, everything was
monochromatic and grey.
405
00:36:43,080 --> 00:36:44,920
There were clouds and they were
grey,
406
00:36:44,920 --> 00:36:46,880
they were the same colour as the
ground.
407
00:36:50,000 --> 00:36:52,440
It's something that you will never
forget.
408
00:36:54,000 --> 00:36:57,800
It makes you realise that we're
truly living on a planet
409
00:36:57,800 --> 00:36:59,520
that's raging.
410
00:37:01,200 --> 00:37:02,960
It drew me closer to my maker.
411
00:37:08,000 --> 00:37:11,080
Volcanoes don't have to explode to be
lethal.
412
00:37:13,400 --> 00:37:16,360
Some are less violent but no less
deadly.
413
00:37:19,400 --> 00:37:22,000
At the Eastern tip of Java,
Indonesia,
414
00:37:22,000 --> 00:37:24,920
is the active volcano of Kawah Ijen.
415
00:37:30,800 --> 00:37:33,240
Dr Clive Oppenheimer travels the
world
416
00:37:33,240 --> 00:37:38,960
measuring volcanic gas emissions to
help predict eruptions
417
00:37:38,960 --> 00:37:42,320
and this volcano is unlike any other
in the world.
418
00:37:48,000 --> 00:37:52,040
Kawah Ijen belches out tonnes of
sulphur dioxide gas.
419
00:37:55,800 --> 00:37:59,560
Dr Clive Oppenheimer is interested in
the chemistry of the lake
420
00:37:59,560 --> 00:38:01,200
in the volcano's crater.
421
00:38:01,200 --> 00:38:05,800
The chemistry is reflecting all of
the gases coming out of the magma
422
00:38:05,800 --> 00:38:08,800
and these are all very, very acidic
gases.
423
00:38:08,800 --> 00:38:12,320
Sulphur dioxide is just one of the
volcanic gases
424
00:38:12,320 --> 00:38:14,280
that make the lake acidic.
425
00:38:17,600 --> 00:38:21,040
And even Clive is surprised by the pH
reading of the water.
426
00:38:22,560 --> 00:38:25,000
That's incredibly acidic.
427
00:38:25,000 --> 00:38:29,560
It's below zero - even battery acid
would give a reading of three.
428
00:38:31,200 --> 00:38:33,240
Most things would rot in the crater
lake
429
00:38:33,240 --> 00:38:35,560
or in the gases around the edge of
the crater.
430
00:38:35,560 --> 00:38:37,600
Metal will corrode.
431
00:38:37,600 --> 00:38:39,080
If you put some sensors in there,
432
00:38:39,080 --> 00:38:43,720
they're probably not going to last
very long 'cause it's so acid.
433
00:38:43,720 --> 00:38:47,360
As well as being acidic,
the lake is extremely hot.
434
00:38:49,000 --> 00:38:52,280
To get that amount of water, 210F,
435
00:38:52,280 --> 00:38:54,720
requires a phenomenal amount of
energy
436
00:38:54,720 --> 00:38:59,280
coming from the deep bowels of the
volcano up to the surface.
437
00:38:59,280 --> 00:39:03,520
Ijen is the hottest acid body of
water on the planet,
438
00:39:03,520 --> 00:39:05,200
I'm pretty sure of that.
439
00:39:10,400 --> 00:39:12,160
On the banks of the acid lake,
440
00:39:12,160 --> 00:39:15,280
sulphur dioxide gas
condenses in pipes
441
00:39:15,280 --> 00:39:17,440
drilled into the side of the volcano.
442
00:39:22,000 --> 00:39:25,120
Local villagers mine the deposits of
pure sulphur
443
00:39:25,120 --> 00:39:27,920
to sell to the sugar and cosmetic
industries.
444
00:39:33,800 --> 00:39:36,040
They carry baskets weighing 70kg
445
00:39:36,040 --> 00:39:38,960
up the steep sides of the volcano's
crater.
446
00:39:56,400 --> 00:39:58,680
I have to say, working in this sort
of environment
447
00:39:58,680 --> 00:40:00,840
is really, really harsh.
448
00:40:00,840 --> 00:40:03,200
It was just horrendous down at the
bottom there.
449
00:40:03,200 --> 00:40:06,960
The visibility was almost zero and
the fumes were coming across.
450
00:40:06,960 --> 00:40:09,120
My eyes are really stinging now.
451
00:40:09,120 --> 00:40:11,720
They feel like they've got gravel
in them.
452
00:40:14,000 --> 00:40:17,720
Human teardrops react with the
sulphur dioxide fumes
453
00:40:17,720 --> 00:40:19,560
to make sulphuric acid.
454
00:40:23,800 --> 00:40:27,240
Life expentancy here is just 40
years.
455
00:40:31,000 --> 00:40:35,080
Kawah Ijen is one of more than a
thousand active volcanoes
456
00:40:35,080 --> 00:40:39,120
that together spew ten million tonnes
of sulphur dioxide
457
00:40:39,120 --> 00:40:41,440
into our atmosphere every year.
458
00:40:52,000 --> 00:40:54,520
Hawaii, March 2008.
459
00:40:56,040 --> 00:41:00,240
An eruption of sulphur fumes punches
through Kilauea's summit crater.
460
00:41:01,800 --> 00:41:03,480
Like many Hawaii residents,
461
00:41:03,480 --> 00:41:07,040
ranger Jay Robinson was taken by
surprise.
462
00:41:08,560 --> 00:41:11,560
One night there's a crack open up
and all the fumes coming out.
463
00:41:11,560 --> 00:41:14,000
For people who've lived up here for
so long,
464
00:41:14,000 --> 00:41:17,160
to look out your back door and a
couple of miles away,
465
00:41:17,160 --> 00:41:21,600
see this huge fume cloud blasting
up, it's a little unnerving.
466
00:41:21,600 --> 00:41:23,480
It's also toxic.
467
00:41:25,440 --> 00:41:27,440
When sulphur dioxide hits the air,
468
00:41:27,440 --> 00:41:29,880
it forms droplets of sulphuric acid.
469
00:41:29,880 --> 00:41:32,600
And here, there's a lot of it being
released.
470
00:41:35,800 --> 00:41:39,200
In the last 24 hours, we've had
around 8,000 to 9,000 cubic tonnes
471
00:41:39,200 --> 00:41:42,480
of sulphur dioxide coming out of
here.
472
00:41:42,480 --> 00:41:45,840
That's enough to fill 100 Goodyear
blimps every day
473
00:41:45,840 --> 00:41:47,360
with sulphur dioxide gas.
474
00:41:49,000 --> 00:41:53,280
In the crater next to the summit,
conditions changed in an instant.
475
00:41:55,000 --> 00:41:58,360
This morning, we were hiking into
Kilauea crater
476
00:41:58,360 --> 00:42:01,960
and it was great air quality -
crystal clear.
477
00:42:01,960 --> 00:42:05,120
You could see through ten miles.
478
00:42:05,120 --> 00:42:08,520
But within 20 minutes, you couldn't
see any more than a mile away.
479
00:42:08,520 --> 00:42:12,280
The fumes were so bad and we started
smelling it, tasting it, coughing.
480
00:42:12,280 --> 00:42:13,800
We got out.
481
00:42:18,200 --> 00:42:20,360
These fumes may be noxious
482
00:42:20,360 --> 00:42:24,360
but volcanic gases also maintain air
composition and climate
483
00:42:24,360 --> 00:42:26,600
so are crucial to life on Earth.
484
00:42:28,200 --> 00:42:32,480
Without volcanoes, the world would be
a very different place.
485
00:42:35,600 --> 00:42:38,360
They have created much of the land
we live on.
486
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This island in the North Atlantic was
formed from a volcanic eruption
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as recently as 1963.
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And in March 2009, another eruption
emerged unexpectedly
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out of the South Pacific ocean off
the coast of Tonga.
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With the Earth in relentless motion,
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volcanoes will always have the power
to both create and destroy.
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itfc subtitles
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00:43:53,000 --> 00:43:54,960
*
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