poverty. in the diamond markets, the scarlet welcome carpets that they just rolled out for me.♪ (vo)150 miles beneath our feet the temperature of the earth reaches 1800 degrees centigrade, hot enough to liquefy solid rock. when under immense pressure, the rock forces its way to the surface the result is an unstoppable volcanic eruption. massive choking clouds of gas and ash are spewed thousands of feet into the air; great torrents of molten rock pour out, overwhelming everything along the way and completely restructuring the landscape. throughout history hundreds of thousands have died as they're caught in the crushing fury. this is a force so great that it has the power to cause the world's greatest disasters.

there are few more awe-inspiring sights than that of a violently erupting volcano. but, what exactly is a volcano

and why are they capable of causing death and destruction on such a terrifying scale? a volcano is quite simply an opening or rupture in the earth's outer crust which enables molten rock and other volcanic materials to escape from the depths. these vents - or volcanoes - are to be found either on land as great mountains; long fissures or trenches in the ground; buried deep beneath the earth; below the seabed or locked under enormously thick sheets of ice. the life of a volcano is measured in three stages - active, dormant and extinct. an active volcano is one which erupts with any kind of regularity, although many years might pass between eruptions. dormant volcanoes are regarded as merely sleeping, even though it could have been for many thousands of years. no-one knows when they will wake

again. it could be 5000 years into the or it could be next week. lastly, a volcano which is extinct is believed to be completely dead, with absolutely no chance of a rebirth. but, whether they're active, dormant or extinct, every volcano was originally formed in the same way. the earth consists of three basic layers: the crust, the mantle and the core. the depth of the crust ranges from about 18 to 60 miles beneath solid land and six to seven under the seabed. the mantle, a dense hot layer of semi-solid rock, is 1800 miles deep and extends down towards the earth's outer core, a seething cauldron of molten liquid nearly 1400 miles thick. finally there is the earth's inner core - its center - a

solid mass of metal 800 miles thick. much of the magma - or molten rock - which ultimately reaches the surface of the earth where it emerges as lava, forms towards the top of the mantle. it's then pushed up into the earth's outer shell, or crust, where it erupts through weak zones either on the surface, deep underground, beneath the sea, or under an icecap. most volcanic eruptions - as well as earthquakes - are created by the movement of gigantic slabs of rock known as tectonic plates which lie beneath the crust. believed to have been formed more than two-of-a-half billion years ago, the largest of these plates is up to 125 miles thick and they are - quite literally - the size of continents. they constantly move, collide and grind against each other, as

they're put under enormous pressure by the intense heat generated by the earth's core far below. at 6000 degrees centigrade the outer ring of the core is as hot as the surface of the sun. when the plates meet, and grind against each other or pull apart, they create major geological activity at their boundaries, resulting in volcanoes and earthquakes. countries which lie at the edge of these great subterranean plates - such as iceland just south of the arctic circle in the north atlantic ocean, japan, the philippines and indonesia - are particularly prone to volcanic activity. more than 75 percent of the world's most active and dormant volcanoes lie in what's known as the ring of fire, a 30,000 mile long horseshoe circling the pacific basin on the ocean floor. it extends from tierra del fuego at the most southerly tip of south america, up through north

america and canada before heading west across the pacific towards russia, then down to japan, china, the philippines, indonesia, new guinea and, finally new zealand. the ring - which is also a source of intense earthquake activity - was formed millions of years ago by the shifting and collision of the great subterranean tectonic plates lying many miles below. named after vulcan, the mythological roman god of fire volcanoes have been wreaking havoc since the dawn of history. they come in a variety of shapes and sizes and include strato-volcanoes; shield volcanoes; sub-glacial and submarine. as professor bill mcguire of the benfield greig hazard research center, university college london, explained, the most commonly recognized type is the strato-volcano. >>most people's idea of a

volcano is a lovely symmetrical coneand this involves magma coming up, reaching the surface, being extruded either as lava or as explosive eruptions as ash and these layers of ash and lava gradually accumulate until you're left with a classic cone shape. (vo)formed and built up over thousands, if not millions of years, such volcanoes are considered to be the most dangerous to man and his environment. in fact, out of the 1500 volcanoes known to have burst into life over the last 10,000 years, 700 are strato-volcanoes. one of the most famous strato-volcano eruptions of all time took place in ad79 when mount vesuvius in italy blew its top after lying quiet for 800 years, destroying the neighboring roman towns of pompeii and herculaneum. although the numbers can only be estimated, more than 3000 people

are said to have died, either suffocated by a tide of volcanic ash ten feet high or choked to death as they were overcome by deadly clouds of poisonous gas. no one stood the slightest chance as they were overwhelmed by what's known as a pyroclastic flow. >>pyroclastic flows. they're formed during explosive eruptions and they consist of very high temperature mixtures of scorching volcanic gas and very hot ash which blasts across the surface of the earth at velocities which can actually exceed the speed of sound. so these are truly devastating phenonmena. (vo)vesuvius, situated near naples on the southwest coast of italy, is the only active volcano on the european mainland. it last erupted in march 1944, killing 27 people, destroying a

large part of the town of san sebastiano and causing considerable damage to a nearby us airforce base. vesuvius is regarded as one of the world's most dangerous volcanoes and is under constant scrutiny from scientists looking out for signs of the next eruption. professor franco barberi of rome university feels it's just a matter of time. >>we don't have any reason to believe that this volcano is extinct to the contrary. the probability that vesuvius will erupt again in the future is very high. you're about to watch an ad message created by a current tv viewer for hershey's air delight. >>during the blind taste tests today you'll be tasting five different kinds of chocolate. okay ladies, let's try chocolate number 4. it's the one right in front of

you. >>oh! >>hurh! >>umm. >>okay now taste your final piece of chocolate. >>umm! umm! ohh! >>umm, ah-hum. >>umm! >>ahh! >>hershey's new air delight milk chocolate, a lighter, airier meltier hershey's happiness. in 2012 alone. go to our website, current.com. up next it's out to the campaign trail. a surprising new poll, and that's next right here inside "the war room."

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i have the most common type of atrial fibrillation, or afib. it's not caused by a heart valve problem. i was taking warfarin, but my doctor put me on pradaxa instead to reduce my risk of stroke. in a clinical trial, pradaxa® (dabigatran etexilate mesylate) reduced stroke risk 35% better than warfarin. and unlike warfarin, with pradaxa, there's no need for regular blood tests. that's really important to me. pradaxa can cause serious, sometimes fatal, bleeding. don't take pradaxa if you have abnormal bleeding and seek immediate medical care for unexpected signs of bleeding, like unusual bruising. pradaxa may increase your bleeding risk if you're 75 or older, have a bleeding condition like stomach ulcers, or take aspirin, nsaids, or blood thinners, or if you have kidney problems especially if you take certain medicines. tell your doctor about all medicines you take any planned medical or dental procedures and don't stop taking pradaxa without your doctor's approval as stopping may increase your stroke risk. other side effects include

indigestion, stomach pain, upset, or burning. pradaxa is progress. having afib not caused by a heart valve problem increases your risk of stroke. ask your doctor if you can reduce your risk with pradaxa. (vo)italian volcanoes which are perceived as a continuing threat include stromboli, located on an island a few miles off the north coast of sicily. known as the lighthouse of the mediterranean, stromboli is one of the world's most active strato-volcanoes, having erupted more or less continuously for at least the last 2000 years. italy is also home to europe's largest active volcano, mount etna on the north-east coast of sicily. midway between a strato and a

shield volcano, at 10,750 feet etna is more than two-and-a-half times the height at vesuvius and boasts the longest period of known eruptions in the world - 3500 years the last time etna erupted was in 1995 and it's been rumbling ever since. so much so that from april 2000 onwards air traffic has been diverted around the volcano rather than run the risk of flying directly overhead. but even etna pales into insignificance compared with krakatoa in the sunda strait indonesia. when this volcanic island erupted in august 1883 the sound of the explosion was so great that it could be heard more than 3000 miles away. in fact the blast is said to be the loudest sound ever made on earth. the eruption - one of the

largest in history - also resulted in a 120 feet high tsunami which killed around 36,000 people in java and sumatra. nearly 20 years later a volcano on the other side of the world also caused enormous loss of life. on the morning of may 8th 1902 mount pelee, a strato-volcano on the caribbean island of martinique, erupted with a thunderous and deafening roar. long thought to be dormant pelee had begun emitting steam accompanied by a series of minor explosions, a few weeks earlier. this spread alarm throughout the island, especially in the city of st pierre which lay four miles from the base. but, just as people were trying to head for safety, pelee exploded with murderous fury. a vast torrent of lava and clouds of ash completely

overwhelmed the city, killing 30,000 people in what would turn out to be the deadliest volcanic eruption of the 20th century. and, although this occurred more than 100 years ago, pelee is still regarded as one of the most dangerous volcanoes in the caribbean. fortunately, not all eruptions end in tragedy. but on june 24th 1982 one came pretty close. while cruising at 37,000 feet above the indian ocean, south of java, all four engines on a british passenger plane mysteriously shut down after flying through a thick dark cloud. as the plane went into a long controlled glide towards the sea, captain eric moody made an announcement. >>i said, ladies and gentlemen we have a small problem. all four engines have failed. we'll do our utmost to get them going. i trust you're not in too much distress. i'd have been terrified if i'd have been downstairs.

(vo)but it was not until emerging from the cloud at around 12,500 feet that the engines could be fired into life again. as the plane headed for an emergency landing, captain moody discovered another serious problem. >>it wasn't until we'd actually got down towards the city of jakarta that i realized that the windscreen had gone opaque. the only bit we could see out of was a two inch strip down each side, on my extreme left or the extreme right of the first officer's window. and i flew the aeroplane standing up. and then we got to about 100 feet over the end of the runway. i sat down and quickly did the straps up and said to the other two, we're not going to die now. and the aeroplane almost landed itself. it just kissed the earth. it was wonderful. (vo)it later emerged that the plane had inadvertently flown into a huge cloud of ash thrown high into the atmosphere by

mount galung gung, a volcano on java, which had erupted earlier that day. >>volcanic ash and commercial aircraft just don't mix. the reason for that is that the ash gets into the aircraft engines. when the pilot finds that they're in an ash cloud they try and climb above it- that means they have to put power on, it heats up the engines, it melts the ash into the turbine blades and they stop. (vo)after strato-volcanoes the most common type is the shield, a gradually sloped hill or mountain, so called because its shape resembles that of an ancient shield. probably the best known example of a shield volcano is kilauea on hawaii in the pacific. one of five volcanoes on the island it is thought to be the most intensively studied volcano anywhere in the world. said to be the home to pele, the hawaiian god of volcanoes, kilauea has erupted 34 times since 1952 - but at a fairly

low level - making it one of the world's most active volcanoes. it was actually a shield volcano which set off the first major known eruption around 1645bc when the island of santorini in the aegean sea was blown apart in a massive explosion. the island, which consisted of a series of overlapping shield volcanoes lying 125 miles south of the greek mainland, was buried under 98 feet of porous volcanic rock. in what was one of the greatest volcanic eruptions the world has ever seen, santorini was - quite literally - torn apart creating a vast central lagoon - or caldera - 1300 feet deep and flanked by soaring 1000 foot high cliffs. although most of the inhabitants& of santorini managed to escape the eruption is believed to have been responsible for the

collapse of the ancient minoan civilization when the island of crete, 70 miles to the south was overwhelmed by a giant tsunami which engulfed and crushed everything in its path.

(vo)the next major type - sometimes known as tuyas - are sub-glacial volcanoes which develop deep beneath the icecaps in places like iceland and

british columbia in canada. because they are unable to break through the ice - even when erupting - these volcanoes have broad, flat tops. submarine volcanoes, lie under the sea. when active, particularly in shallower waters, they make their presence known by blasting steam and hurling debris high above the surface. others are so deep that the enormous pressure and weight of water overhead means that even the mightiest eruption causes barely a ripple. however, this was hardly the case when a submarine volcano erupted off iceland in november 1963. as the crew of a fishing boat was working about 20 miles from the coast of iceland in the north atlantic, they were astonished to see a huge column of dark smoke and ash bursting from the sea. it was the latest in a series of volcanic eruptions which had

begun 426 feet below the surface. ten days later the outline of a new island began to take shape. the eruptions continued intermittently for almost four years until june 1967 when the island - made up of volcanic rock - was a mile wide and up to 300 feet high. since then the volcanic island - named surtsey - has remained peaceful, eventually attracting plant life, sea birds and seals. but, as iceland is already home to some of the world's most active and unpredictable volcanoes, no one can be sure how long this apparent tranquillity will last. over time, the people who live on iceland itself and the surrounding smaller islands have become used to living with danger. but they can still get taken by surprise.

at 1:55 on the morning of january 23rd 1973, ten years after surtsey emerged, iceland was subject to one of the most famous eruptions of modern times when - after lying dormant for at least 5000 years - a volcano on heimaey, a small island six miles off iceland's south coast, burst into life threatening the lives of everyone in its shadow. a vast river of molten lava erupted from a mile long fissure and headed for vestmannaeyjar, the island's port. fortunately, however, it was moving slowly enough to give the authorities time to start an orderly evacuation of the town's 5300 inhabitants. six hours after the eruption began most of them were on their way to the icelandic mainland, either by plane or fishing boat.

although the lava and other volcanic material had first emanated from a fissure in the ground - rather than a mountain - after two days it began forming a huge cinder cone. as the cone grew the lava started flowing from its summit. by the end of february the cone had reached a height of 600 feet and was expelling a torrent of lava and rocks up to 100 feet deep. as the inhabitants of heimaey helplessly watched its terrifying onslaught they named the cone eldfell, or fire mountain. but a few weeks later, as the great one thousand yard wide river of lava, looked as if it might reach and destroy the main source of the town's livelihood, it's fishing harbor, something had to be done. so, in a desperate attempt to stem the deadly flow, seawater was sprayed onto the river of

molten rock to try and solidify it or at least divert its relentless progress. special pumping equipment was brought in from the us and a ship with the ability to direct massive amounts of water moved into the harbor. the operation, in which nearly one-and-half-billion gallons of water was sprayed non-stop onto the lava, using 19 miles of pipe and 43 pumps, lasted until early july 1973 when it was deemed a success. a short time later, with the harbor saved, the inhabitants of heimaey began to return. they were faced not only with a massive clear up of their island, but they also had to begin the daunting task of rebuilding hundreds of houses and other buildings destroyed in the eruption. the best known - and most catastrophic - eruption in icelandic history occurred in june 1783 when - following a

series of increasingly powerful earthquakes - a fissure 16 miles long opened up at skaftar in the southern part of the island. skaftar - also known as laki - produced one of the greatest lava flows ever seen. by august 1783 it was up to ten miles wide in places and 100 to 600 feet deep. by the time skaftar calmed down eight months later, the entire island was covered in ash and the lava had wiped out 20 villages. professor thor thordarson of edinburgh university described the sequence of events. >>right now we're standing on the laki lava flow at the mouth of the skaftar river gorge where it burst out of the skaftar river gorge in june 1783. the laki lava flow started with an eruption that started on the 8th of june in the year 1783 and lasted until february 7th in

1784. this eruption produced an enormous amount of lava and as an example of that what we see right here, behind us, is a gorge which was at least 50 meters deep - might have been as deep as 100 meters right at this spot - is now completely filled up with lava. as the lava was moving down the gorge flowing at such velocity that right in front of the gorge it looked like a glowing sea of lava. this lava actually poured out of the gorge here to the south and covered the plains in front of the mountains which you see here in front of us, and in the end it covered 600 square kilometers. (vo)the devastation caused by the eruption led to a famine resulting in the deaths of nearly 10,000 people, or one tenth of the population. three-quarters of the island's livestock - including nearly

200,000 sheep - also perished. the region has remained calm ever since. but no matter how much death and destruction has been caused by different types of volcanoes - in particular the strato-volcano - there is one other class which makes all the others look small and weak. if you have copd like i do you know how hard it can be to breathe and what that feels like. copd includes chronic bronchitis and emphysema. spiriva helps control my copd symptoms by keeping my airways open a full 24 hours. plus, it reduces copd flare-ups. spiriva is the only once-daily inhaled copd maintenance treatment that does both. and it's steroid-free. spiriva does not replace fast-acting inhalers for sudden symptoms. tell your doctor if you have kidney problems glaucoma, trouble urinating, or an enlarged prostate. these may worsen with spiriva. discuss all medicines you take, even

eye drops. stop taking spiriva and seek immediate medical help if your breathing suddenly worsens your throat or tongue swells you get hives, vision changes or eye pain, or problems passing urine. other side effects include dry mouth and constipation. nothing can reverse copd. spiriva helps me breathe better. does breathing with copd weigh you down? ask your doctor if spiriva can help.

(vo)this is the super volcano. the term is not one recognized by scientists. in fact it was actually first coined on a british television program to describe volcanoes which - although buried deep beneath the earth's surface - have the potential to cause devastation on an unimaginable scale. >>super eruptions are called vei8 eruptions and this means they sit at point eight on what's known as the volcano explosivity index.

now this runs from zero up to eight, it's actually a measure of the violence of a volcanic eruption and each point on it represents an eruption ten times more powerful than the previous one. so, if we take mount st helen's for example, which was a vei5, we can represent that eruption by a cube of this sort of size, this represents the amount of material ejected during that eruption. if we go one step higher and look at a vei6, something of the santorini size, for example, then we can represent the amount of material ejected on santorini by a cube of this sort of size. but if we go up to vei8 eruptions then we're dealing with something on an altogether different scale - a colossal eruption. and you can represent a vei8, some of the biggest vei8 eruptions, by a cube of this sort of size. it's absolutely enormous. (vo)the eruption of a super volcano would destroy enormous areas of land, adversely affect long term weather patterns by blocking out the sun with vast quantities of ash and sulphur

dioxide, and threaten mankind itself by triggering a new ice age. fortunately super volcanoes are extremely rare and eruptions even more so. in fact the last time such a volcano manifested itself was thought to be around 74,000 years ago on sumatra. but when the volcano, named toba, blew, it was believed to have been the most powerful eruption for the last two million years. the lava which flowed from this volcano covered nearly 8000 square miles and the material spewed into the atmosphere cooled the planet for years to come. the eruption also left a giant crater known as a caldera, about 30 miles across. more than two million years earlier an even greater super volcano eruption took place in what would become yellowstone national park in wyoming.

it created a caldera 60 miles across, discovered only when scientists were examining aerial pictures of the entire area. much to their concern they also discovered that the ground in the park was nearly 30 inches higher than when last measured in 1923. this was clear and alarming evidence of a massive build up of magma, or molten rock, under the caldera. the yellowstone super volcano has erupted three times in 2.2 million years, with the last occurring 640,000 years ago. some scientists believe that the next eruption is already overdue. if and when it happens, the consequences not just for north america, but for the whole world would be too awful to contemplate.

although there are often warning signs that a volcano is building up towards a major eruption, it is nonetheless shocking when it actually happens. mount st helens, usa, 1980. on march 20th 1980, observers picked up seismograph readings indicating minor earthquake activity 20 miles north of mount st helens, a strato-volcano in washington state. seven days later - as the earthquakes continued - the volcano suddenly roared into life, spewing ash 20,000 feet into the atmosphere and forming a 250 foot wide crater on the summit. during the first week in april there was another eruption lasting five hours. then there was an ominous development as the north side of the mountain began to bulge.

as this was a sure sign of enormous pressure building beneath the rock face, a state of emergency was declared. a mass evacuation of people living in the area got under way and the national guard was called in to prevent anyone from getting in too close. by early may the bulge was 2000 feet long, 500 feet high and still growing. finally, at 8:30 on the morning of may 18th, mount st helens exploded with a roar which could be heard 200 miles away. one side of the mountain was blown away completely as a vast plume of smoke and ash rose twelve miles in the air. the force of the explosion knocked down trees 20 miles away and resulted in a crushing torrent of molten rock, ash and other volcanic material. this poured down over the surrounding countryside at

terrifying speed, killing nearly 60 people and destroying everything in its path including thousands of acres of forest farmland, houses, roads, bridges and train tracks. charlie crisafulli of the us forest service recalled the immediate effects of the devastating eruption:. >>ash columns started being ejected into the atmosphere, eventually circling the globe within two weeks, and within 100 miles making the day turn into night. first ash started coming down then it became dark, street lights came on. people were driving around with their headlights on, using their windshield wipers to try and rid the ash from their view so they could make it home. (vo)as well as the people who died, the disaster resulted in the death of more than 7000 big game animals, such as bears, deer and elk. since then mount st helens has been the subject of intense

scientific study. no one wants to be caught in it's path if amd when it blows again. mount pinatubo, the philippines, 1991. at 1:42 on the afternoon of june 15th 1991, after a series of smaller eruptions, mount pinatubo, a strato-volcano on the island of luzon in the philippines, exploded and overwhelmed the surrounding countryside. the eruption was followed by a devastating typhoon. by the time it was over nearly 850 people were dead; 100,000 made homeless and more than 200,000 acres of farmland ruined. the eruption, the second largest of the 20th century - after katmai in alaska on june 12th 1912 - was ten times more powerful than mount st helens. when pinatubo erupted it threw

so much volcanic material into the atmosphere that temperatures around the world fell for the next 15 months. rising nearly 6000 feet above sea level, pinatubo had remained dormant for the last 600 years. however, there had been warning signs a year earlier, in 1990, when a major earthquake shook the ground 60 miles northeast of the pinatubo region. at the time observers wondered if it was the precursor to an eruption. but nothing fhappened until mid-march 1991 when villagers living around the base of the volcano began to experience earth tremors. this was followed on april 2nd by a cloud of ash which coated the landscape. now, as the authorities became concerned, 5000 of the 30,000 people living near mount pinatubo were evacuated.

the minor earthquakes and eruptions of ash continued until early june when the appearance of a lava dome at the volcano's summit forced the evacuation of remaining 25,000 people. at the same time 18,000 staff and their families at clark air base, a us military installation just 16 miles east of mount pinatubo, were also evacuated. ten days later - on june 12th - the danger zone around the base of the volcano was extended to nearly 20 miles. by now, 58,000 people had been cleared from the area. then on june 15th mount pinatubo finally erupted, with devastating consequences. the disaster was compounded by a typhoon which

was passing 50 miles northeast of the volcano as the eruption occurred. this increased the death toll even more. you know what is happening in 15 minutes? come on you know by now. it's "the young turks." you know over this weekend there is going to be an avenue african american centered weekend in miami beach. what did the police decide to do? perhaps arrest 2,000 of those visitors. and they haven't even done anything wrong. then how has it worked out for president obama when he has agreed with the republicans? disastrously. we'll show you those examples as well. and then get aload of this

question, is nancy pelosi too conservative? debate on that. we have a conservative on this show. that's nothing but fun. i'll tell you one more story. what if a country does the exact opposite of our educational system? what happens then? it turns out they finish on top. we'll explain. ♪

[ kristal ] we're just taking a sample of all our different items in our festival of shrimp. the crab-stuffed shrimp are awesome! tequila lime tacos. [ man ] delicious! [ male announcer ] it's festival of shrimp! for $12.99 try any two shrimp creations like new barbeque glazed shrimp. offer ends soon. we're servers at red lobster. and we sea food differently. (voapart from a few subsequent minor eruptions, which lasted until july 1992, mount pinatubo has remained dormant ever since. but it would take the filipinos years to recover from the disaster which caused half a billion dollars worth of damage. and once the us military left clark air base they never returned, leaving the philippines government to take over. the us also abandoned the naval base at subic bay, 50 miles southwest of mount pinatubo. >>the panel chairman have also agreed that although the effects of mount pinatubo have rendered

continued us operations at clark airbase and the smaller facilities virtually impossible, there still exists a requirement for orderly withdrawal and turn over of all facilities to the government of the philippines. (vo)mount nyiragongo, the congo, 2002. during the latter half of 2001 a strato-volcano started sending out signals that it was about to blow, forcing more than 400,000 people to flee for their lives. finally, on january 17th 2002, after several months of low level seismic activity mount nyiragongo in the democratic republic of the congo finally erupted with unbelievable ferocity.

a huge fissure measuring eight miles across opened up on the south side of the 11,400 foot mountain. a great river of lava 1800 feet wide and six feet deep, erupted from the fissure and swept relentlessly towards the city of goma which lay twelve miles to the south. having heeded the warning signs earlier most of the population had already left, many of them heading for safety in neighboring rwanda. for some, clutching a few meager belongings, this involved a long and hazardous trek across the still smouldering ash and lava. nevertheless 45 people died, either from carbon dioxide poisoning or through being crushed by falling buildings. as the lava swept through the city, it set fire to countless homes and other buildings, adding to the chaos by hurling blazing oil drums

high into the air. by the time the danger had passed, 4500 buildings had been destroyed and 120,000 people left homeless. the eruption of mount nyiagongo is believed to have been the most destructive volcano in recent times. since the nature of volcanoes was first understood, they have long been the subject of intense study. there is no longer any mystery about how they were formed; how they vary from type to type and what causes them to erupt. however, even though there have been enormous strides forward in recent years, predicting when and where a volcano will next erupt is still far from being an in fact, most of the scientists - known as volcanologists -

who make a study of volcanoes, prefer to use the word forecast, rather than predict. they have a variety of instruments at their disposal including seismographs which detect movement in the ground and highly sensitive seismic tilt-meters. these measure and record the slightest change in the shift and flow of magma far below the surface. they also have the information gathered by satellites. this enables the study of gas formations in the atmosphere above a volcano and the likely spread of the fallout. the more scientists know about a particular volcano the better chance they have of estimating how it will behave. but, with the possible exception of the volcanoes on hawaii which are constantly on the move, most of the world's active volcanoes - many of therefore, difficult to access - erupt only intermittently. hawaii is home to the first volcano observatory in the us.

founded in 1912 and based near kilauea, one of the world's most active volcanoes, many of the now universally accepted prediction techniques were developed here. however, if there is any one particular eruption which resulted in a scientific breakthrough, it was mount st helens in 1980. although no-one predicted exactly when the volcano would erupt - or its magnitude - scientists knew that it was about to blow on a major scale. this gave the us forest service time to evacuate a large number of people from the area. and, even though nearly 60 people died in the eruption, it's believed that the prompt evacuation most likely saved the lives of another 20,000. since then mount st helens has become one the most intensively studied active volcanoes in the world, giving scientists - working at a nearby observatory - the opportunity to produce

vast amounts of invaluable data. although a great deal of the volcanologist's time is spent sitting in front of a computer screen, analyzing streams of data, there is no substitute for the real thing. so, they will put themselves in harm's way by getting up close to an active volcano gathering gas, ash and lava samples; measuring changes in temperature and checking cracks in the ground. over time, although wearing protective suits and being extremely cautious, several volcanologists have been killed by sudden bursts of volcanic activity. so, you guys grew up together. yes, since third grade... what are you lookin' at? not looking at i anything... we're not good enough for you. must be supermodels? what do you model gloves? brad, eat a snickers. why? 'cause you get a little angry when

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(vo)although monitoring volcanic activity is much more precise than it used to be, it is still extremely difficult to predict where and when the next major eruption will take place. in fact, probably the only volcanoes in the world where future events can be viewed with any degree of confidence are the great volcanoes on hawaii. mount vesuvius in italy - which destroyed pompeii in ad79 - has a record of erupting every 50 years or so. the last eruption occurred in 1944. so scientists are on constant alert, looking out for the first signs of the next eruption. >>major difficulty here and on any other volcano in the world is that we don't have the capability of assessing the precise moment of the eruption. (vo)vesuvius is still regarded as one of the most dangerous

volcanoes in the world. around two million people live in its shadow and - if not evacuated in time - they would be completely overwhelmed during the first 15 minutes of a major eruption. >>the majority of these houses were built without any permission and according to italian law they should have been destroyed, but nobody of the local administration took the courage of taking these drastic measures. so really the problem is very serious because the risk has increased enormously in the last decade. (vo)if vesuvius were to erupt again on a major scale it could well be the most catastrophic and destructive natural disaster that the world has ever known. for 250 million years volcanic eruptions have shaped the

surface of the earth, forming mountains which returned rain to the sea, unlocking minerals which have created life itself. they have also resulted in death and destruction on a huge scale. because, despite the impressive advances in forecast technology, volcanoes remain the most volatile and highly unpredictable force on the planet.