Aftermath To The World's Deadliest Natural Disasters [4K] | Mega Disaster | Spark

[Music] there's a way to make an entrance my destiny it was now a conspiracy of witches download today [Music] volcanic eruptions are one of the most powerful forces on earth from spectacular lava fountains to deadly explosions they can bury entire cities under superheated clouds of ash and gas or turn quiet rivers into seeded torrents of mud and debris scientists are struggling to understand these unpredictable time bombs we were taken by surprise by what turned out to be an unprecedented event we'll circle the globe profiling some of the most significant eruptions of our time each more devastating than the last each leading to a potential mega eruption that could change the world as we know it volcanic eruptions are dramatic reminders that our world is a living planet their destructive force is four billion years old a force that demands respect volcanoes combine the beauty and the beast the power to create and to destroy from the very beginning they've served a vital function releasing heat gas and minerals from deep beneath the earth's crust these by-products proved vital to human life creating the earth's atmosphere if volcanoes did not exist neither would we to me they're one of the most beautiful things you can ever witness but to the people who live under them they're the most terrifying and destructive thing you can ever witness cameraman jeff mackley's mission to film the world's volcanoes comes with risks on one mountain he avoided death by moments when a lethal mixture of hot gas and ash just missed him there was a loud roar like a freight train and a pyroclastic flow came down the valley that we'd just been in so yeah another five minutes either way it would have been curtains for us mackley risks his life to record volcanoes beauty others risk theirs to recall their power many of us have experiences that could either have gone one way or the other depending upon just just something small that happened in the past 60 years volcanic eruptions have killed at least 27 scientists even so their quest for knowledge continues on average between 50 and 60 volcanoes erupt every year about 20 are erupting at any given moment all are vents in the earth's surface most take place within the ring of fire an area around the pacific basin where tectonic plates collide allowing molten rock or magma to be released thick magma loaded with gas triggers explosive eruptions thinner magma with less gas is less volatile to compare and categorize eruptions scientists have developed the volcanic explosivity index or vei scale each notch up the scale means a higher ash cloud more rejected material and greater explosive energy the events profiled here begin with a non-explosive eruption and peak with a planet-altering super eruption one that experts say will eventually happen hawaii is a stunning tropical paradise but under the brilliant sand and lush forests simmers a cauldron of tremendous heat and violence this is the site of one of the most spectacular volcanic creations on the planet all of the hawaiian islands are volcanoes built over 70 million years by a powerful geological formation called appropriately a hot spot the hot spot is a narrow zone which has an excess amount of heat in it the heat rises and near relatively near the earth's surface this heat melts the rocks and then that melted rock erupts as lava [Music] february 1983 kilauea on the big island of hawaii sends lava fountains 80 meters into the air because the magma is thin and doesn't contain much gas the eruption is not explosive but it's still dangerous for seven years the eruption continues the lava inches forward slow enough to outrun but totally unstoppable in february 1990 it reaches the fishing village of kalapana hundreds are evacuated it became a very painful experience actually to watch this because it was just creeping through town you know every week or so another blocks worth of houses were gone residents have time to pack up their belongings and in some cases their entire homes others can only watch as the lava destroys their past we moved out that afternoon and two days later our home was engulfed by flames and we were able to watch the lava come into our yard by december the entire village is gone buried under more than 15 meters of molten rock behind me is the eastern edge of what used to be the town of kalapana in 1990 there were about 150 homes out here and they've been buried by about five stories worth of lava despite the hardships caused by the volcano some hawaiians see beyond their personal tragedy they respect the power and the beauty of the lava a force they worship as a goddess named pele we don't really resent or feel like um it was a loss for us because we we know that pele this is her land her aina and she can come anytime she wants to go anywhere she wants to the hawaiians were unable to stop kilauea's enormous lava flow but 4 800 kilometers away an entire nation took a desperate stand when a volcano threatened one of their towns on january 23 1973 the eldfell volcano erupts on the icelandic island of hindi a slow-moving lava flow more than 10 meters high threatens to engulf the village of vesmania the majority of the village is evacuated but a dedicated team stays behind to confront the formidable force over five months crews spray approximately six million cubic meters of sea water onto the lava flows nearly four million cubic meters of molten lava is converted into solid rock the village is saved such a herculean effort is impossible with kilauea the flow is simply too great the lava that destroyed kalapana plows on pouring into the sea in a spectacular collision where the lava goes into the ocean it makes one of probably the most beautiful places on the flow field but it's also one of the most dangerous below the solidifying lava unstable sand is prone to sudden and violent collapse all of a sudden all this hot lava is on the surface it just snaps off the ocean rushes in and it creates huge explosions that send gigantic plumes of material up in the air and they cover maybe three or four football fields in area sending out rocks the size of like soccer balls or basketballs all over the area this impressive display is a glimpse into prehistoric times when volcanoes first formed land the same process is still happening today it builds new beaches and then these beaches the lava then can flow over and it builds that out a sequential set of beaches and then lava flow and beach lava flow and it builds out a new piece of land that we call a lava delta since 1983 kilauea has displaced almost 200 families and destroyed millions of dollars worth of property in that same time it's added more than 200 hectares of land to the island continuing the 70 million year process that created all of hawaii it's a stunning example of how a volcano creates and destroys at the same time its slowly oozing magma is a permanent threat but rarely produces a violent explosion in our next event thicker magma trapped in a geological powder cake triggers a much more explosive volcanic eruption lethal white hot clouds of gas descend on thousands of people wiping out an entire caribbean capital [Music] and later in our mega disaster scenario a super volcano strikes the heart of europe demolishing a major city and casting a shadow over the entire planet the stunning lava fountains and flows of kilauea on the big island of hawaii both create and destroy but rarely are lethal but there are much more explosive and dangerous volcanoes ones that spew out deadly gas and ash clouds one such volcano ravaged half a nation and sent 19 to their graves montserrat is a lush and tranquil caribbean retreat but in 1995 the sufria hills volcano quiet for nearly 400 years rumbles back to life over the next two years multiple eruptions shoot ash thousands of feet into the air the capital of plymouth is evacuated twice each time the residents return hoping the volcano's rage is over on june 25th 1997 those hopes are buried [Music] at 1 pm a giant ash cloud erupts nearly 10 kilometers high in the next 30 minutes close to 800 degree mixtures of ash and rock race downhill at more than 100 kilometers an hour [Music] the lethal clouds are called pyroclastic flows roy daly lives three kilometers from the volcano he hears the eruption and rushes outside to see the flow racing by him less than 50 meters away started to feel some heat and the darkness started to roll over the wood so i got in my car and i sped away like crazy i drove on top the hill away from the pyroclastic flow the force of the thick mixture of gas ash and rocks flattens everything in its path roy watches helplessly as entire villages are destroyed he's managed to escape the pyroclastic flows but he's not out of danger yet i was scared that i thought i was gonna live it was so dark that if you put your hands to your face you couldn't see them hot ash raining longer than you real hot ash i felt scared i couldn't move i couldn't see i couldn't breathe properly so of course i thought i was gonna die but i was hoping i didn't die and i didn't roy is finally evacuated by helicopter but not everyone is able to escape dr sue lachlan is the director of the montserrat volcano observatory and a witness to the eruption the maximum speed of pyroclastic flows on that day could have been in excess of 150 miles per hour even though people saw it coming there was very little they could do to make their escape the nearly 8 million cubic meters of flow covers thousands of square kilometers of land damages or demolishes more than 100 homes and destroys the island's only airport other than one ferry service monserrat is cut off from the rest of the world but the volcano is not finished over the next four months eruptions and pyroclastic flows continue to devastate the island we had over 70 explosions in one month sometimes there were four explosions a day each explosion generated a mushroom cloud which rose rapidly to great heights above the volcano each explosion generated pyroclastic flows which spread in all directions around the volcano you can see behind me the impact on gage's mountain of surges as they came over the mountain during one of these explosions and singed and burned all the vegetation there the pyroclastic flow's toll on the island's natural resources is immense the human toll is 19 lives the cause of this violent and tragic eruption lies deep below the lush island the same process that created this tropical paradise threatens to destroy it here the north and south american tectonic plates collide with and plunge below the caribbean plate in a process called subduction the subduction takes place at about 130 kilometers depth that's about 80 miles below the surface of the earth as the plate goes down parts of it melt and this forms magma and the magma works its way up to the surface over many thousands of years unlike kilauea the sufia hills volcano produces thick magma over thousands of years it forms the classic steep volcanic cone called astrato volcano the magma contains a variety of gases all under intense pressure it slowly rises until it reaches the earth's surface when the pressure is released just like a bottle of champagne the gases suddenly expand and the volcano violently erupts thousands of kilometers away in barrie italy scientists are studying sufia hill's most lethal side effect the purpose of these experiments is to understand the dynamics of pyroclastic flows so to be prepared for the next events dr deleno and his team load about 200 kilos of actual volcanic ash from mount vesuvius into a cylinder pressurized gas creates an explosion that ejects the ash the volcanologists track the height direction and density of the ash with a variety of instruments and high-speed cameras the models here are big enough to be accurately scaled up to actual events something that could not be achieved in a lab the experiments have determined that both the amount of magma and the force applied to it are critical in the creation of pyroclastic flows next researchers will match the test with the topography of specific volcanoes they'll then be able to pinpoint specific areas where pyroclastic flows are likely to strike local authorities can evacuate those areas prior to an eruption potentially saving many lives but tragically for those in the path of stratovolcanoes like sufria hills pyroclastic clothes and ashford aren't the only threats every year between twelve hundred and two thousand millimeters of rain fall on montserrat heavy rains run down the channels created by the pyroclastic flows transforming them into massive mudslides called lahars most of this debris that we see around us is caused by lahars washing all the pyroclastic flow debris further down the hill and progressively burying plymouth under all this mud and boulders lahars have buried so much of plymouth that the city has been permanently abandoned they were the volcano's final salvo in a brutal one-sided war the sufria hills volcano destroyed more than a thousand homes left more than half of the island uninhabitable and destroyed the nation's capital about 4 500 people remain on the once thriving island of 12 000. it was sad to see people just having to go buy droves out of mantra but it was understandable because these people had lost their properties it was a pure strength why i stayed here i mean you had no place to go no place to live with families and friends being shocked up still in schools and churches it was difficult and it was very sad but the volcano has also created new opportunities that have helped revitalize the island volcano related tourism is rising roy daly owns and operates a tour bus business people are anxious to see a live volcano i don't think there's any place on the face of the earth that you could see a live volcano from approximately one mile from it bubbling and rolling and walking right though hills multiple pyroplastic flows and lahars were lethal and destructive its eruptions never exceeded a three on the volcanic explosivity index but when a vei-5 fires a single 24-megaton blast it destroys thousands of acres of land and kills dozens of people and later scientists explore the potential for a super eruption one unseen in modern times one that could kill millions the pyroclastic flows and the hearts of the sufria hills volcano on montserrat destroy the island's capital killed 19 and changed the nation's landscape and thousands of lives forever in 1980 america's pacific northwest experienced a different and rare type of eruption that acted like a giant cannon blast flattening entire forests and killing dozens the cascades are an 1100 kilometer long majestic range stretching from canada to northern california hundreds of thousands of hikers and skiers find refuge and adventure here but in the spring of 1980 one of the cascades crown jewels begins to fracture in march small earthquakes ripple deep below the peak of mounts and helens after more than 120 years of slumber the mountain is awakening this seismicity is typical of volcanoes when they reawaken because as molten rock tries to push its way up underneath the volcano it makes a lot of noise in terms of shouldering aside the the hard rock that makes the edifice of the volcano itself on may 17 keith rongholm a geophysics graduate student intrigued by the mountains activity decides to get a closer look mount st helens was erupting about every five or eight days i had gone to a place called bare meadow to try to get a view of one of these small summit eruptions ronholm gets far more than he bargained for at 8 32 on the morning of may 18 a magnitude 5.1 earthquake rips through the volcano's north side 2.8 billion cubic meters of earth falls at speeds of up to 257 kilometers an hour i was reading a book in in my my truck when i heard some people yelling and i looked over at the mountain and the entire north side of the mountain was sliding down the earth's movement releases the enormous pressure holding the magma inside the volcano a 24 megaton blast over 1800 times more powerful than the hiroshima atomic bomb shatters the north face of the mountain the blast is unusual in that it doesn't shoot straight up as most eruptions do this is a rare lateral blast slamming a huge cloud of rocks trees and ash approximately 180 degrees out from the mountain there was a puff of dark gray churning ash and within 10 10 15 seconds that that ash had expanded out and it covered the entire mountain all of this was happening silently and it was no noise to reinforce my my flight response i was 10 miles away and you don't at least initially feel like something's going to hurt you from from 10 miles away so i stood there and i took pictures and i was fascinated by by watching this event as the huge cloud of debris races over the two ridges between the volcano and ron holm at 483 kilometers an hour keith suddenly realizes he's in serious danger as i'm driving out i took one last picture over my shoulder and it's a little motion blurred but i couldn't take time to to frame it or or stop because i was driving and i remember looking back at the little parking area realizing that i was the last person to leave and thinking maybe i'd waited a little bit too long because this cloud was rushing towards me luckily for ron holm the strongest part of the blast heads north and northwest the portion that's heading north east directly towards him has less energy allowing him to escape down the mountain the lateral blast spews ash and gas up to a height of 24 kilometers less than an hour later a vertical eruption sends more ash skyward into this grim scene flies jess hageman with the washington army national guard most of the trees were blown over by the eruption and we're talking about 14 15 miles downstream of of mount st helens the whole landscape was changed made you feel like like sort of a gnat flying around the universe because in comparison to the size of the eruption it was it was amazing amazing and horrific 800 degree pyroclastic flows race down the steep flanks at up to 129 kilometers an hour in some places they are 37 meters thick in the early hours of the disaster the enormity of the destruction to the landscape is impossible to comprehend but it only takes one sobering moment for jess hageman to realize the human toll it was on this ridge right straight ahead of us here that we found the first two survivors in the blast area and that turned out to be jim scamanki and his partner leotti and we eventually were able to pick those two people up uh leondi died in the hospital after we got him there but jim is still alive and survived rescuers find a handful of stunned survivors but the eruption kills 57 mostly campers and tourists nine hours after its start the eruption ends scientists struggled to comprehend the enormous scope of the event before the eruption mounts and helen stood at 2949 metres tall now it's 401 meters shorter the blast destroyed enough trees to build 300 000 houses thousands of logs still litter spirit lake five kilometers from the summit the volcano shot out more than 508 million tons of ash that spread across the entire us in three days two days after the eruption geologists get their first close look at the desolation it was like walking on the moon i have never seen anything like it this entire area which is 600 square kilometers or 230 square miles was totally devastated there wasn't a living thing in that entire area not an insect or a bird or an animal there was only one color and it was this gray color of the deposits the ground was covered with hot rocks and there were fumes and hot gases coming out of the ground all over the place in the months following the eruption teams of experts carefully study every facet of the mountain oddity of monster helens was that some people heard the eruption as far away as canada but eyewitnesses like keith rongholm just 16 kilometers away heard nothing because of the way the temperature structure in the atmosphere gets cooler with height that the sound waves from explosions are bent away from the surface of the earth and when they reach the stratosphere and the temperature again increases with height they're bent back down so no one between six and sixty miles from mount st helens heard the may 18th eruption since 1980 the mountain has experienced tens of thousands of small earthquakes and numerous minor eruptions most significantly since 2004 the volcano has been continuously erupting lava creating a giant lava dome that is still growing today its volcanologists like rick lahoosen's job to find ways to monitor all of this activity all we needed was a way to get our instruments out there very quickly without putting people on the ground in harm's way and yet still be able to monitor changes in the eruption so what we came up with is this stainless steel super structure which kind of looks like a daddy long leg spider so we kind of call them spiders this is a gps antenna which receives timing signals from satellites and lets us locate exactly where this is the signals go into the computer system and then the data come out at the request from computers back in the office and are transmitted out through this antenna with the spider securely attached to a chopper it's time to head into the belly of the beast as they approach the crater the new lava dome is visible spewing out sulfur dioxide gas and steam this is proof that magma is reaching the surface with the potential to build to another eruption the most dangerous moment for rake and his pilot comes as they place the spider on the lava dome this close to the crater floor exploding rocks or a sudden burst of steam could easily kill them operating with the precision of surgeons the men carefully place the spider directly on top of the lava dome within seconds the device begins gathering and transmitting data [Music] at the cascades volcano observatory in vancouver washington lahouzen analyzes the spyder's digital camera images time-lapse photography shows the lava dome's formidable growth what's really phenomenal about this is how much rock is coming out of the ground it's taller than the empire state building it's coming up at five meters per day more than 200 meters across and it's right here in our backyard no conclusions have been drawn yet about the lava dome's rapid growth geologists warn that an eruption similar to the 1980 event is possible but unlikely they are certain however that future eruptions of some sort will occur whatever its future the mountain's recent past continues to reverberate today especially for those who are there it's just an amazing event to witness that we normally think of the earth as being a very static stable environment that we that doesn't change but when you get to watch a volcanic eruption and you watch a giant piece of the earth slide away followed by this dynamic churning ash cloud that flattens tens of square miles of forest you realize how powerful nature can be and how powerful geologic forces can be monster helen's vei5 lateral blast destroyed a massive amount of land and killed 57 people just one notch up the scale a vei 6 volcano kills hundreds when its huge eruption is followed by a long series of deadly side effects and later scientists revealed the unthinkable effects of a mega eruption that they guarantee will happen sometime in the future the vei 5 lateral blast eruption at manson helens flattens 600 square kilometers of land and killed 57 people but there's one volcano that's in a class by itself it killed hundreds afflicted millions and affected the entire planet its eruption was just the first in a series of tragic events that went on for days months and years that continue to this day luzon is the largest of the philippine islands it's home to 56 million people the capital city of manila and mount pinatubo for centuries thousands have lived on and around the mountain farmers harvest rice and other crops from its fertile soil what many locals didn't know or believe is that the mountain is a volcano even most experts who knew it was thought it was inactive on june 9th 1991 the mountain erupts for the first time in more than 500 years eruptions earthquakes pyroclastic flows and ash batter the island day and night geologist dr kelvin rodolfo arrives four days later the amount of ashes are falling so thickly you couldn't see any more than 20 feet there were pieces the size of chicken eggs that were landing on us on june 15th a massive eruption spews five cubic kilometers of volcanic debris 35 kilometers high the top of the mountain collapses triggering a series of large earthquakes rodolfo is one of thousands trapped in the city of a longer pole 33 kilometers from pinatubo i was terrified continually doing the eruption every three minutes or so there was a noticeable tremor one of the magnitude that would cause you impulsively to want to run outside of a building but outside the scene is equally terrifying reddish lightning was darting horizontally above people and the claps of thunder were practically simultaneous with with lightning this intracloud lightning is caused by static electricity in the ash cloud it's seldom dangerous because it strikes horizontally instead of vertically still fear of the conditions outside stops many locals from sweeping the ash off their roofs something that will have fatal consequences on the same day as the eruption a typhoon strikes luzon the heavy rains mix with the ash since ash consists of fine particles of rock and minerals adding water turns it into a cement-like substance for those with several centimeters of ash on their roofs the mixture is a deadly one the passing typhoon saturated the ash with water making it a lot heavier causing roofs to fall in and pull the walls of houses here in africa as if that isn't enough vast pyroclastic flows fill the valleys around pinatubo with debris once again the typhoon turns a volcanic by-product into a lethal weapon lahars lahars form when a large amount of debris rapidly mixes with a huge amount of water the powerful mass churns downstream destroying anything and anyone unlucky enough to be caught in their path if you imagine a bulldozer traveling perhaps uh 15 miles per hour hitting the substructure of a bridge the bridge is taken out and that's the impact that that large rafted boulders had after nine nightmarish hours the eruptions end more than 300 people are dead and tens of thousands are homeless as bad as things are they could have been much worse in the months prior to the eruption locals reported seismic activity ongoing scientific monitoring confirmed the reports guided by experts who pointed out specific high-risk zones officials evacuated more than 58 000 people in the days and hours leading up to the eruption prior to the eruption we had made maps that anticipated where the tefra would fog and that depended on the seasonal winds but in still another deadly development the typhoon changed the wind direction areas that had been considered safe were inundated with a deadly mix of tephra or ash and rain that crushed homes and the people in them as thousands begin the massive cleanup the volcano's effects become global one month after the eruption the huge ash cloud circles the earth in the upper atmosphere sulfur dioxide is converted into sulfuric acid aerosols they reflect the sun's radiation away from the earth cooling the entire planet's surface by one degree the effects on the earth's atmosphere will last more than two years back in the philippines the volcano's after effects continue in the three months following the eruption heavy rains trigger more than 200 lahars as time progressed and the the flows eroded deeper and deeper into the lahars the channels got larger and larger and became much more efficient conduits for the slurries to flow down to help the hundreds of thousands of people in harm's way lookouts are stationed upriver when they sign to lahar they radio priests like father nestor tayek who ring their church bells in warning the bell's sounds would be heard by the community any time of the night like an alarm a warning [Music] but once again a twist of fate conspires against the people of luzon in october 1995 another large typhoon strikes the island and lookouts are put on alert unfortunately uh the heavy rains that triggered the lahars were not yet loaded with sediment when they passed this consequently the lookouts radio that nothing but flood water is coming down the mountain but as the water runs down the channel it erodes a lot of loose material bulking up the lahar into a mixture estimated at eighty percent sediment and only twenty percent water the larger the percentage of sediment the faster and more powerful the lahar it strikes with incredible force it was making this nice this sound just like rampaging horses it was coming closer suddenly it invaded our parish church the second floor of my rectory where i live was buried and i climbed on top of the bell tower the lahar still kept coming you can actually hear the lahar still rising burying the second floors of most houses you can hear people screaming it was very dark you can't see a thing the lahar kills dozens and buries the entire town of baccalaure like cement the remains of the lahar dry quickly and turn rock hard today the entire village is built on top of the dried out lahar eerie reminders of the devastation are everywhere including father ness's church where a new floor had to be built over seven meters of mud since 1991 thousands of lahars have killed nearly 400 people and destroyed more than 42 000 homes but scientists fear that pinatubo is still not finished on top of the mountain a new threat is forming not magma but years of heavy rainfall that have created a giant lake in the volcano's caldera it breached its banks in 2002 generating a massive lahar geologists are concerned about a huge fault that runs through the area the rocks weakened by the fault are more easily eroded and the walls of the channel are very steep and so landslides could fall and plug the channel and cause like the lake level to rise again and then spontaneously flush out in large amounts that would generate new large lahars the lake contains 100 million cubic meters of water 46 000 people live below it all would be threatened by a major lahar to date the eruption and lahars have affected almost 2 million people for the battered but resilient residents of luzon pinatubo is a constant threat for scientists it's an ongoing spectacle in geological training we're accustomed to thinking in terms of small events repeated over millions tens of millions or even hundreds of millions of years to generate mountains but here we see events happening in within a day a huge amount of power plastic material a huge hole developed over over a matter of hours or days and that to me is is very fascinating the devastating byproducts of the pinatubo eruption had long-term effects that killed hundreds effects that continue to this day but a mega eruption one that volcanologists are certain will happen could threaten millions the vei six eruption of mount pinatubo and its after effects killed more than 700 sent a huge ash and gas cloud around the globe and lowered the earth's surface temperature if we were to experience a vei 7 super eruption it would be 10 times larger it would destroy all life for dozens of kilometers it would drastically change the earth's climate and scientists say it will happen someday the five million people in the naples italy area live in the highest volcanic risk zone in the world approximately 11 kilometers to the east is mount vesuvius it's 79 a.d eruption killed more than 20 000 in pompeii and other villages since then the volcano has erupted 50 times most recently in 1944 vesuvius looms over naples as a constant threat but 15 kilometers to the west is a far less conspicuous but potentially far more deadly volcano campy flagray campy for gray is an enormous 13 kilometer wide caldera with a series of craters scattered inside 350 000 people actually live within the caldera walls since campi flagray is not a tall imposing volcano like vesuvius it attracts little attention but volcanologists like steve self know the massive power it contains here we are in the middle of a volcano that's got a remarkable history of eruptions since it was first formed about 35 000 years ago this area has had repeated eruptions forming the craters like the one we're in we're in a volcanic crater that still has uh steam vents acting and hissing as you can hear behind us these steam vents reach temperatures of nearly 700 degrees to a casual observer that's impressive but to experts the vents along with ground shifts are ominous warning signs an indicator of campy flagray's power lies in deposits left by a massive eruption 35 to 40 000 years ago it was 10 000 times larger than the 1991 pinatubo eruption these 80 meter tall cliffs in sorrento 30 kilometers from campy flagray are composed to volcanic material left from the super eruption volcanologist giuseppe mastro lorenzo knows their geological proof that enormous pyroclastic flows swept through this entire area the pyroclastic flow moves this way as a turbulent cloud and then i'm placed in mass that's causing the the boring of all the area around naples what scientists know about campy flagray's past gives them a realistic model of what could happen in its future the scenario begins with a massive disturbance somewhere within the vast caldera a super eruption more than 242 cubic kilometers of dust gas and pumice hurtle into the air it would bury a very large areas the size of a major city or more in uh thicknesses of ash that uh hundreds of feet thick enormous pyroclastic flows race from the volcano at near supersonic speeds buildings that aren't already buried by ash are knocked down by the force of the flows or incinerated by the 800 degree temperatures the once proud city is completely annihilated the death toll from the flows and ash is apocalyptic we can assume that in case of a super eruption several million of people will be killed the casualties and destruction spread far beyond the immediate area the eruption column grows to a staggering height of 30 kilometers heavy ash falls smothers towns near the cold era and spreads as far away as rome 225 kilometers away [Music] the city is pelted with more than 20 centimeters of ash enough to cause roofs to collapse and kill thousands of people smaller amounts of ash fall across eastern europe and parts of asia but even small amounts of ash cause big problems even a dusting of a few centimeters would create total uh disruption to transport systems to water supplies to uh things that we regularly rely on in our daily life enough to bury plants enough to strip the branches and leaves off trees and things like that the enormous quantity of ash and sulfuric dioxide released by the volcano triggers a planet-wide condition one affecting millions atmospheric modelers are predicting that the temperature could drop several degrees centigrade and this would affect weather for many years four or five years perhaps after after a very large eruption and temperatures would change areas where crops would grow may not be able to grow those crops huge areas of vegetation would die millions could starve to death ultimately the entire planet and everyone on it would be dramatically affected if you consider the number of volcanoes super volcanoes around the world that could potentially produce super eruptions recognizing the fact that there are probably several out there that we don't know about yet we've still got a huge amount to learn about this scale of volcanism then there's possibly something like a one percent chance that an eruption could happen in the next hundred years which is quite high actually high enough for scientists to urge discussions of this type of disaster in the international community volcanologists know that there is no way to prevent an eruption so they learn from the past and study the present in order to help mankind prepare for the future [Music] tsunami the ocean's deadliest force giant waves with immense power massive unstoppable deadly a level of destruction that was you know over hundreds of miles of the coastline we'll travel the globe investigating some of the world's most devastating tsunamis each bigger than the last each packing more punch each taking us one step closer to a mega tsunami a wave that will not just rewrite the record books it will erase them no coastline on the planet is truly safe from tsunamis they're caused by massive displacements of water triggered by the earth's most powerful forces earthquakes landslides and volcanic eruptions as long as we have earthquakes on earth and landslides the the various phenomena that create tsunamis we're going to have tsunami waves uh it's just a matter of time when the next one strikes tsunamis are dramatically different from the typical waves that constantly sweep across the planet they can travel faster than 800 kilometers per hour they can stretch for thousands of square kilometers across the ocean's surface it's a good 15 20 feet tall easy they strike with huge mass and terrifying velocity the most common method of gauging their height is run up the wave's highest point of impact on land each tsunami profiled here has a higher run-up than the last over 100 major tsunamis have struck in the past 100 years killing hundreds of thousands and destroying billions of dollars of property but they are not the biggest tsunamis to strike the planet scientists have found startling evidence that even larger waves have occurred in the past mega tsunamis these things have been described as culture ending events experts believe that a mega tsunami lies in our future to understand its power scale and potential we'll first investigate five of the most destructive tsunamis of the past 60 years each has its own character each has its own story each brings us closer to a mega disaster hawaii is a tropical paradise that attracts millions of tourists but this pacific island holds a dark secret it's blasted by more tsunamis than almost anywhere else on the planet the hawaiian islands sitting as they do in the middle of the pacific ocean are affected by tsunamis from all regions of the pacific the ring of fire is a volatile fracture zone surrounding the pacific ocean plate 90 percent of the world's earthquakes occur here earthquakes are the most common cause of tsunamis which is why hawaii gets hit often and from all directions destructive tsunami struck here in 1837 1868 1877 1923 1946 52 57 60 and 64. this makes it the unofficial tsunami capital of the pacific 2 28 am april 1 1946 a magnitude 8.1 earthquake rips through the aleutian islands off the coast of alaska huge stretch of the ocean floor is uplifted displacing the entire column of water above it a massive pulse of energy propels a wall of water a tsunami towards hawaii at nearly 800 kilometers per hour [Music] three thousand eight hundred kilometers away in the small seaside village of la pahoy hoy children and teachers gather to prepare for the day's classes masu mcshane is one of the teachers we were in our cottages and the akionas who lived in that house that's no longer there knocked on our door and said come see the tidal wave at first glance it's deceptively innocent we looked over and the wave ocean sucked out and then it came in a little bit more like emptying a bathtub and sucked out again and we said this is a tidal wave i don't think much of that what mazu doesn't know is that tsunamis are not single waves they move forward in what's known as a tsunami train a group of waves of many different sizes first waves are seldom the largest so what appears to be insignificant is actually the precursor to something much much bigger and then it did it again and this time it went in further and sucked out more and we thought a twin died away tidal wave how interesting and odd as the water recedes an extraordinary 152 meters masu and her roommates pose for a photograph masu stands captivated while a third wave approaches famous last words i said i hope this will be a big one i kept coming and that was the first time we ever thought to be afraid as the tsunami approaches shore it behaves like a giant train wreck the front of the wave slows while the back continues to push the waves energy is compressed forcing it to stand and lift out of the sea this got bigger and so we dropped the camera ran inside i can remember the water just crashed in the windows the roof fell down the wave tosses marsuum like a rag doll at first in towards the school but then suddenly out towards the sea and i knew i was going to die masu spends the next nine hours clinging to debris before finally being rescued she is the only lucky one all of her roommates perish at the school sixteen children and five teachers are lost but the tsunami is not finished with hawaii 37 kilometers south of la pahoy hoy the sleepy trading town of hilo bay is also called unawares here the tsunami destroys nearly 500 homes and businesses kills 96 and injures hundreds descriptions of the 1946 tsunami were that it came across the breakwater with the greatest of ease just overcame it and then washed across town other people described seeing boulders blasted out as the water surged across walter dudley is an oceanographer from the university of hawaii in hilo bay for more than 20 years he studied tsunamis one of his most significant findings is that their destructive power is caused not just by the wave itself but also by what's underneath them one of the things that makes them such an interesting phenomenon to study is that they are all different and as they travel across the oceans they're affected by the ocean floor along their tracks so the waves are constantly being bent or refracted and then as they come ashore they are further altered no two pieces of coastline are the same each has its own unique undersea topography that affects the waves differently in hilo it is the natural rounded shape of the bay you can think of a bathtub and his little children get in a bathtub they can slosh the water back and forth and they quickly find out that there's a speed at which the water will really move the first two waves to hit the bathtub shaped hilo bay caused the water to slosh back and forth when a third wave arrived it combined with the sloshing water to produce a larger and more destructive wave it pretty much wiped out everything that was on the ocean side of town in the main parts of downtown it picked up the railway and it twisted the railway rails into pretzels the third wave reached a run-up height of nine meters it destroyed most of the foreshore of hilo bay but less than 15 years after the 46th disaster hawaii would again be hit by a deadly tsunami a wave bigger than the last that would defy logic and bring hilo to its knees once more on may 22nd 1960 the largest earthquake in recorded history ruptures the earth's crust off the coast of chile 1 000 kilometers of the ocean floor is violently thrust up 20 meters spawning a monster tsunami it's so huge and powerful that it crosses the entire pacific ocean slamming into hawaii on the way [Music] this time technology installed since the 1946 quake warns residents of hilo bay five hours in advance but the warning falls on deaf ears when the preceding 12 years about three out of four alarms had turned out to be small tsunamis so instead of inspiring fear let's get away from this potential disaster i think it inspired curiosity because it is a fascinating phenomenon let's go down and watch although the civil defense were saying people evacuate there were a lot of us me included that out of curiosity went down to look you know to see what was going to happen local real estate agent al inouye and many others assume that because this wave is coming from the southeast and hilo faces the north the bay will be spared they are wrong just after midnight the first wave strikes you could hear people yelling and screaming behind me they were being caught in a wave that was an experience because you know it's it's and it still stays in my mind all the screaming and yelling and and i couldn't do anything about it sounded like several trains you know rushing down a track i mean it was really a roar and you know you can hear the crashing of uh houses against each other it's hard to describe it was just a sound that you don't want to hear again i mean it was horrible dawn breaks on a nightmare 61 people are dead and more than 700 buildings destroyed or severely damaged [Music] the 1960 tsunami took locals and experts by surprise after thorough study scientists discovered a remarkable aspect of the tsunami as the wave reached the shallow water off the southeast coast of the island the middle of the wave slowed while the outside of the wave kept moving causing the wave to wrap around the island then just as in 1946 the natural shape of the bay added to the tsunami's destructive power this time the largest wave had a run-up height of 10.5 meters one and a half meters higher than in 1946 but hawaii wasn't the only location struck by the monster tsunami it roared thousands of kilometers across the pacific striking virtually every coast including japan where 122 people died tsunamis have an incredible amount of energy and as they travel across the ocean they use up very very little of that it's when they come ashore that all that energy is unleashed the 1946 and 1960 tsunamis gave scientists new insights into the complex behavior and ocean crossing power of these giant waves but when a local tsunami hits japan it strikes with larger and more powerful waves than the 46 and 60 hawaiian tsunamis combined and there's no time to evacuate and later a tsunami that combines sudden impact with awesome size a mega disaster the 1946 and 1960 hawaiian tsunamis had run-up heights of 9 and 10.5 metres shaped and intensified by the ocean floor and coastline they smashed the island communities with unexpected force but there's another tsunami hotspot where a larger and more deadly wave struck without warning second only to hawaii japan is the most tsunami-prone location in the pacific the japanese have been hit so many times by these giant waves that they created the word tsunami meaning harbour wave to describe these terrifying events these waves can come from as far away as chile or as close as 80 kilometers offshore the locally generated tsunamis pose the greatest danger they strike within minutes of being formed and with awesome power [Music] 10 17 p.m july 12 1993 a magnitude 7.8 earthquake rips the ocean floor off the coast of hokkaido the epicenter is only 80 kilometers from the tiny island of okushiri and generates one of the biggest and most destructive tsunamis japan has ever experienced fisherman jiro andachi from the village of aonai knows about tsunamis he survived one 10 years earlier that also hit okushiri when jiro feels the earthquake he knows a tsunami is probable he quickly evacuates his wife and children from their seaside home sending them to higher ground in the car while he shuts off the gas he moves swiftly but not swiftly enough just four minutes after the quake the first wave hits him with overwhelming force as it surges to an incredible 15 meters it started to pull me back into the sea i held onto something and thought that i must run to the mountain somehow manages to find firm ground he flees to the safety of a nearby hill in a few terrifying minutes the tsunami destroys 80 houses and fishing shacks but the danger is not over out of the darkness a second wave strikes homes boats cars and trucks spared by the first wave are smashed to pieces fires erupt as gas pipes burst aonai is under siege jido and other survivors rushed to the waterfront to help be injured we heard people shouting for help they were calling help me help me i had a lot of voices women's voices and children's voices suddenly amidst the cries for help jiro hears something that chills his heart suddenly i heard a familiar voice between wave breaks so i shouted is that you action and then i heard daddy i heard that from the darkness his young daughter is somewhere in the raging sea as jiro's family fled the tsunami's first wave rolled their car and held them into the ocean gyro dives into the turbulent waters normally i'm a great swimmer but this was incredibly difficult sometimes i was swimming but i couldn't move forward at all and other times i'd suddenly be pulled backwards by the sea miraculously father and daughter make it to shore seven hours later the coast guard finds jiro's wife and son kilometers out to sea clinging to debris as dawn breaks the tsunami's power becomes horrifically clear large parts of aonai are completely flattened fires continue to rage and most of the fishing fleet is lost across the island 437 houses are destroyed and more than 800 severely damaged 198 people are dead the aftermath of the disaster confronts scientists with an intriguing mystery the two waves that hit aonai came from completely different directions the first wave of the tsunami came from the west area where the seismic center was and it attacked only the low part in the south area of onai but the second wave came from the east away from the tsunami source the second wave came in just 10 minutes after the first and it attacked all of this area [Music] the first wave that hit the west coast of okushiri came directly from the source but then just like in hawaii the tsunami wrapped around the island creating a second wave that struck aonai from the opposite direction but the wraparound effect does not explain why the tsunami hit okushiri with such brutal force the reason is the extreme proximity of the event which created the tsunami after a tsunami is generated it radiates out like ripples on a pond as the ripples expand wider and wider the energy spreads out over a larger area the closer the source of the tsunami is to the impact zone the more concentrated the energy okushiri was only 80 kilometers from the source so it received the full brunt of the tsunami just north of aonai the waves reached a staggering 31 meters today the legacy of the 1993 tsunami is set in concrete huge walls up to 11 meters high and extending 14 kilometers along the coast stand guard against the sea powerful steel gates protect river mouths and the harbour is bolstered by concrete blocks to reduce wave impact these ramparts against the waves are stronger than normal sea walls for good reason the forces they must withstand are utterly different normal waves form through the transfer of energy from the wind to the ocean surface tsunamis are generated by phenomenal transfers of energy even the largest wind waves have a maximum wavelength from crest to crest of a few hundred meters tsunamis can have wavelengths of hundreds of kilometers when they hit they keep coming and coming in a unique experiment scientists in japan are measuring the impact of those forces at this lab in kanagawa engineers are using the largest man-made tsunami in the world to help design stronger coastal structures this machine can generate waves more than three meters high propelling 300 cubic meters of water down a 180 meter long chute the best thing is to know the characteristics of the power of tsunami in each situation and build buildings according to those characteristics leads a team that measures the power of tsunamis under controlled conditions this tsunami is only two-thirds of a meter high but it strikes with one ton per square meter of power to demonstrate what that kind of power can do arikawa puts himself in the waves line of fire without the rope and harness he'd be swept away by this miniature tsunami bigger tsunamis are even more powerful this 2.4 meter wave hits with the force of 10 tons per square meter even after the initial impact it continues to surge forward with a sustained pressure of 4 tons per square meter the tsunami in okushiri was much higher and hundreds of times more powerful scientists here believe their studies will translate into stronger and better engineered structures capable of withstanding tsunami strikes once we can reduce the power the reduced destructive power of tsunami coming ashore would not cause as much damage the okushiri event shows how destructive a local tsunami can be it strikes with undiluted power and too quickly to respond but that disaster was eclipsed by a far bigger and more deadly tsunami a wave generated by an earthquake so powerful it moved the entire planet a wave that takes us one step closer to a mega disaster the tsunami that hit okushiri japan came from just 80 kilometers away and reached a run-up height of 31 meters it killed 198 people and destroyed most of the fishing village of aonai but it pales in comparison to the deadliest tsunami of modern times [Music] 7 58 am december 26 2004 deep in the ocean off the coast of sumatra indonesia 1200 kilometers of the earth's crust ruptures in the second largest earthquake ever recorded the 9.3 quake shatters buildings and destroys lives but it is just a forerunner of an even more horrific disaster an epic tsunami spreads across the entire indian ocean striking 12 countries as with okushiri japan the local effects are the most immediate and the most devastating 16 minutes after the quake and 250 kilometers from its epicenter northern sumatra is struck by 35 meter high waves the capital city of banda arche is decimated more than 160 thousand people are killed coastal engineer jose borrero arrived in banda aceh four days behind the tsunami i've seen hurricane damage and i've seen some flood damage before and i've seen a lot of tsunami after effects before also but this definitely was the worst what was amazing about it was the scale seventy percent of all buildings in bunda arche are flattened more than 70 kilometers of coastline show evidence of wave heights above 30 meters [Music] it was a level of destruction that was you know over hundreds of miles of the coastline the same level of destruction so it wasn't just isolated pockets of areas that were wiped out but the entire coast and then the entire city of mondagi [Music] an hour and a half after bandar aceh is levelled the tsunami strikes thailand a wall of water swamps beachside villas hotels and villages that wave is a good 15 20 feet tall easy more than 8 000 people die two thousand kilometers to the west on the island nation of sri lanka 100 billion tons of water surges inland killing 35 000 people and leaving another half million homeless in all nearly 230 000 people die in the most devastating tsunami in recorded history the death toll higher than for all other major tsunamis in the past 300 years combined the power of the earthquake that triggered the tsunami was staggering the entire planet's sea level rose by a tenth of a millimeter every spot on earth moved at least one centimeter as scientists struggled to comprehend the enormity of the event a bizarre anomaly comes to light one that took an additional tragic toll the morning of december 26 is quietly dawning on the peaceful shores of gaul sri lanka british tourists camilla and dominic wilby are sleeping in their beachside bungalow with their 11 year old son hector suddenly dominic is awakened by a strange noise i went outside onto the veranda and i noticed that the water which should have been at low tide was up against the wall of the of the garden what dominic is seeing without realizing it is the first sign of the tsunami at the point of its creation the bottom of the tsunami called the negative wave went east towards thailand and indonesia while the top called the positive wave went west towards sri lanka when the bottom of a wave arrives first gravity sucks the water out lowering the sea level when the top of a wave arrives first it comes like a flood this is what the welby's are experiencing i didn't know what it was and at that moment the floor exploded the tsunami rushes in destroying the bungalow the force of the water was phenomenal you know to to be exploded out of your bed you know to feel a piece of furniture just to be thrown up into the air and to be thrown off it and to have to jump it's just very weird and and to then be sucked out and tossed around like being in a washing machine couple grab their son and scramble into the bathroom with each wave with the intensity of each waves it would fill up the shower cubicle completely we would be swirling around underwater trying to you know regain our purchase on whatever we could find as the waves continue to pound the concrete walls of the bathroom begin to crumble hector is trapped under a large piece of concrete struggling to keep his head above water the idea of your child dying before you is it's nothing worse a third wave surges over hector's head he's seconds from death but instead of drowning him miraculously it lifts the concrete slab off his foot and releases him the wave that's caused so much death in this one instance is life-saving but mostly the peculiar behavior of tsunami waves proves deadly surging forward and sucking back billions of tons of swift moving water carry a dangerous mass of deadly projectiles broken timber glass metal and vehicles the third wave turned gall into one of the hardest hit areas in the nation as the people of sri lanka struggle to recover tsunami scientists like james gough arrive in the devastated nation one of the really difficult things when you go into these areas is you are going there because you have a mission to learn about the tsunami from a scientific point of view it's very important to learn these things and yet there is the human tragedy going on around you and it's very difficult to isolate yourself from that human tragedy amidst the horror goff and his colleagues discover the oddity of the third wave so there's gall quietly sitting there recovering from being hit by two waves and then back how and why the gall area was hit by this third wave intrigued experts where did it come from the first clue in the mystery was uncovered by looking at a global map sri lanka is directly in the line of fire of the tsunami sri lanka was basically staring down the barrel of a loaded gun in a way the second clue came only after careful analysis of the tsunami's unique behavior so the tsunami wave goes all the way past sri lanka heading off to the east coast of africa but on the way whack it hits into the maldives and a lot of the energy is reflected back from the maldives and the first place that hits is gaul the tsunami was so powerful its reflected energy carried a third wave 800 kilometers back across the indian ocean in total over 4 000 people died in the gaul region the tragedy confirms scientists theories about the phenomenal reflective power of tsunamis the indian ocean tsunami continues to provide scientists with complex and compelling new data most of which is still being processed it's really difficult to say right now what the boxing day tsunami taught us uh compared to what we didn't know before because it's taught us so much it taught us that we actually don't know a lot and that we have a lot more to learn what the welby's learned is that life is fleeting and precious in appreciation for their survival and in recognition of the thousands that did not they spearheaded a fundraising effort back home in england to date they've raised 25 000 for the people of gaul many mysteries about the indian ocean tsunami remain unanswered one of the biggest questions is how the highest waves could possibly have reached a staggering run-up height of 35 meters far beyond what had been thought physically possible by an earthquake triggered tsunami but as huge as that tsunami was it is not the biggest wave to strike in recent history landslides can trigger a different kind of killer wave producing a tsunami of monstrous size and scientists believe a mega tsunami looms in our future a wave of such epic proportions that nothing like it has been seen since prehistoric times the 2004 indian ocean tsunami unleashed a series of enormous and deadly waves that had run-ups of 35 meters but they are dwarfed by another wave that forced scientists to become detectives what they discovered was a new kind of tsunami one of unimaginable size and power [Music] in a remote bay in southwest alaska a native legend tells of a beast that shakes the ocean and destroys those who walk its shores in 1958 a local fisherman came face to face with that beast a mysterious wave more than twice the height of the golden gate bridge the story of this incredible phenomenon began five years earlier with two american geologists on assignment in remote lituja bay alaska we were in the bay mapping the geology and primarily interested in the stratigraphy because of the oil potential of that part of the of the gulf of alaska they didn't find any oil but they did find one of the scientific mysteries of the century george plafka was one of the scientists one of the obvious things you see when you go when when you're in that bay if you're looking closely is that the trees are of different ages as you go away from the shoreline plafka and his colleague noticed that a band of younger trees circled the entire bay hundreds of meters above the water the scientists knew this dramatic change in vegetation meant a large-scale disaster had struck the area but they saw no evidence of fire or avalanches and so we speculated about what that could be and had all kinds of ideas about glaciers shoving forward very rapidly the other was that there were submarine slides going on at some of the deltas along the margin of the bay or that there was breakouts of large amounts of water up higher along the glaciers and then they flood down all of a sudden we had everything except the right way the right idea about how those waves could form the geologists left lituja bay without solving their mystery five years later they got their answer [Music] in 1958 howard ulrich takes his eight-year-old son howard jr on a fishing trip to latuya bay so we went into our favorite anchoring spot and and dropped our anchor and made supper and finally about nine o'clock we went to our bunks an hour later the boat starts shaking violently an 8.3 earthquake centered 21 kilometers from latuya bay rips across the water howard and his son rush up on deck just in time to see the most amazing sight of their lives it looked like a big explosion like you've seen big explosions in the water on tv that's exactly what it looked like what happens next defies the imagination as the spray started to settle down out of the bottom of it came this huge wave i would say that the wave was close to a thousand feet high at that time the actual wave traveling at an estimated 112 kilometers per hour the liquid mountain is charging straight for howard and his son just cold black and full of logs just straight up and down it was a actually a pretty horrifying looking sight i just thought you know this is this is the end no no way you're going to get out of this you know in a desperate attempt to keep control of his boat howard turns on his engine and drives directly into the beast started pulling all the anchor chain out and when it got to the end of the chain it just i thought it was going to pull the bow at a boat under but it snapped that chain just like it wasn't even there the giant wave lifts the tiny boat high into the air i looked out over the stern of the boat and we were looking down on the trees and i figured that's where we were going to end up unbelievably their boat rides up and over the wave and the ulriches land back in the bay unharmed two other vessels and their four occupants are not as lucky this incredible footage was filmed the next day everything in the waves path is destroyed no trees are left standing and most soil is ripped off down to bedrock the run-up height of 1740 feet is the world record i think for anything that's happened in historic time and uh it was uh you know it's 500 feet higher than the empire state building that's that's pretty big the earthquake felt by howard triggered a massive rock slide sending 30 million cubic meters of mountain hurtling into latuya bay the debris slammed into the water creating the giant wave it just swooped down a very steep slope and ran out into the fjord and basically forced all the water out of that little arm in front of the glacier and shot it up over the ridge that was on the other side one mystery remained the amount of water displaced exceeded the amount of land that fell into the bay it took 42 years to solve this mystery scientific models determined that the rapidly moving landslide created an air pocket behind the wave preventing the water from sloshing back the force of the air pocket combined with the size and weight of the landslide shot the water out of the bay like a missile it would be the same as if you you know you took a paddle and ran it down pushed into the water full speed at a high velocity just shoved push all the water right out the effects of the giant lituya bay wave remain clearly visible today the event rewrote the history books and changed our understanding of tsunamis forever landslides can and do produce waves far larger and more destructive than ever thought possible [Music] lituya bay's desolate location limited the damage caused by the giant tsunami [Music] but should an even bigger landslide generated waves strike a major city the result will be a mega disaster in 1958 a landslide generated tsunami taller than the empire state building obliterated an alaskan inlet it was a devastating display of nature's power but across the pacific ocean on the gentle slopes of oahu hawaii scientists have uncovered evidence of a potential disaster that would dwarf the indian ocean and latuhya bay tsunamis combined it's almost incomprehensible the the scale the enormity of these things it would be quite a view gerard fryer is a geophysicist from the university of hawaii he uses advanced computer modelling and field data to forecast tsunamis his research has uncovered a potential wave so big that even the best laid evacuation plans may not be enough these things have been described as culture ending events the state would essentially be knocked back to the stone age this maker tsunami would combine the dizzying height of a landslide triggered wave with a tsunami that strikes a densely populated landmass in this case hawaii on the island of oahu locals and tourists alike flock to the sea soaking in the perfect climate and idyllic lifestyle of one of the most iconic coastlines on the planet but in our scenario everyone is oblivious to the fact that less than kilometers to the east a disaster of biblical proportions is about to strike [Music] the mega disaster is triggered by the eruption of the world's largest volcano manalo on the big island of hawaii in the case of monologues and and that's the 800 pound gorilla here that's that's the big volcano that we have to worry about as mauna loa is preparing for eruption the southwest rift zone of mauna loa inflates with magma the entire mountain swells which means that the outer slopes get steeper there are probably a succession of small earthquakes and then maybe a big earthquake that shakes loose this very steep western flank of the volcano almost 1500 cubic kilometers of earth and rock plummet into the sea on impact the land displaces a massive amount of water the ocean rushes back to fill the giant gap from this cataclysmic disturbance emerges the tsunami heading directly for honolulu estimated time to impact 30 minutes this is the direction that a big tsunami would come from uh from from the big island the wave first becomes visible as it stands and breaks on a shallow bank 40 kilometers southeast of honolulu you'd see the sea rear up in front of you that would be huge it would rise up above you the size of a building the size of a 10-story building surging inland at up to 70 kilometers per hour the tsunami slams honolulu because the tsunami's energy stretches down to the ocean floor this wave is not clean water it's filled with sand coral and rock water penetrates 16 kilometers inland before being sucked back out to sea in a lethal maelstrom of wreckage it annihilates nearly everyone and everything in its path these giant landslides as far as we can tell they seem to occur during periods of high sea level when the climate is warm quite why that is we don't know but we are in a warm period right now with high sea level so we should expect something like this within the next 10 or 20 000 years as the unofficial tsunami capital of the pacific hawaii is preparing for the future scientists continue to develop a global network of warning systems based on real-time seismic analysis and deep sea wave sensors alarms will sound as soon as 90 seconds after the initiation of even a small tsunami tsunamis are global sized events with global ramifications they combine the almost unlimited power of the earth with the gargantuan might of the sea they are a humbling reminder of the transience of man and the awesome strength of nature while scientists learn more about tsunamis engineers build stronger coastal barriers and experts implement improved warning systems individual vigilance remains essential and you see the water withdrawing strangely um curiosity shouldn't compel you to go down and see what's going to happen next the alarm bell should be going off it's something that we need to have embedded in our culture in our knowledge base and in our education so that we know what to do when the next tsunami happens not if it's when it's something we need to learn to live with as long as we continue to have the phenomena that create these giant waves we will continue to have tsunamis it's just a matter of time before the next one strikes wow what a tornado tornadoes are unpredictable volatile [Music] the whole country looked like it was in a nuclear blast at some time and lethal i kept talking to myself thinking well this is it they leave behind obliterated towns there were no houses left they were all gone and bewildered scientists it's not an exact science each tornado is unique most dangerous a few deadly from the tremendous to the terrifying to the tragic this is a countdown to a mega tornado one that experts believe will devastate a major american city [Music] the most ominous tornado warning comes when an apocalyptic light darkness fills the sky these clouds are precursors to a powerful storm a supercell [Music] most tornadoes form when a violently rotating column of air stretches down from that supercell to touch the earth in general the faster the wind speeds the more dangerous the tornado surprisingly relatively little is known about these giant killers scientists are literally chasing the mysteries of tornadoes across the great plains of the united states better known as tornado alley more than 400 tornadoes threaten to wreak a path of destruction here every year far more than any other place in the world the main reason ideal atmospheric conditions the mountains to the west the gulf of mexico to the south and the fact that there are no physical barriers between here and the north pole means that we are frequently changing air masses from warm to cold and back again tornadoes are measured using the f scale f for dr theodore fujita who classified tornado strength by estimating wind speed based on devastation the smallest twisters are f-zeros they can reach kilometers per hour about the equivalent of a small hurricane at the other end of the scale are f5s whose winds reach speeds of up to 512 kilometers per hour the tornadoes profiled here rise up the fujita scale from an f2 that rips the roof off the house did you see that to an f5 that lays waste to an entire neighborhood it's all leading up to a mega tornado one that some scientists fear will ravage a primary city 111 kilometers southwest of wichita lies the small town of attica kansas just over 600 people live here it's a town you could easily miss on may 12 2004 a tornado didn't on that day the blue skies over harper county fill with storm clouds shortly after 6 p.m dan smith heisler heads into attica i did some work for the banker in there and i told his wife i said you know it's going to storm today several thunderstorms form over southern kansas one look at these storms tells 30-year veteran meteorologist chuck doswell they might be a breeding ground for tornadoes one of the important ingredients that produces a tornado that we're pretty sure is the wind at low levels has to change direction and speed rapidly with height we call that vertical wind shear the vertical wind shear typically spins the air into an invisible cylinder as the wind speed increases it rises the tornado intensifies and the core pressure drops condensation from the dropping pressure builds down the funnel creating a visible tornado that's exactly what's happening in the southern kansas sky harper county emergency management director mike laureg gets the first tornado warning at 6 45 and when they start giving us those warnings we listen and we say hey we need to start warning our public from there we do not know if this is going to be an f-zero or it's going to turn into the monster in kansas meteorologists carefully follow the thunderstorm as it tracks towards attica about 7 25 in the evening a f2 tornado had made it to ground right up here just on this hill the path of it was right across here as lorec watches in astonishment the tornado tears the roof off a home this act of violence is just one of many the angry skies over kansas are far from finished we thought okay hopefully things are over we got emergency crews set up for that and then it the storm just suddenly it took a life on its own storm chasers tracking the kansas supercell relay information to meteorologists using mobile doppler radar they report the tornado's wind speed location and one other startling fact the storm is producing multiple tornadoes storm chaser yvette richardson seen a supercell create more than one tornado before it can be a very dangerous situation because often people will be looking at the main tornado and feeling that as long as they're far enough away or they're they've taken cover that that they should be completely safe her team and others report seeing 16 tornadoes they vary significantly in size and power the biggest is an f4 roughly 160 kilometers per hour faster and with corresponding wind force about three times larger than an f2 the f4 head straight for dan and donna smith heisler's home i was listening to the radio and the tv and they had exactly pinpointed they knew exactly where it was at knowing a tornado's path gives potential victims an average of 12 minutes warning enough time to save their lives [Music] the smith heislers get the warning but dan ignores it mesmerized by the golf ball-sized tail that often precedes a tornado he refuses to join his wife down in the basement that scared me so i started screaming and get down and the dog would not come down he said sugar won't come and she was going in the door out the door in the door dogs are smart they know so when i screamed at sugar then she came down he came down we started hearing this popping noise well we had a rack of canned goods over there and those cans were popping from the the pressure chain it sounded like popcorn going off over there the tornado batters dan and donna's home with winds estimated at more than 322 kilometers per hour and that's when i got hit on the head with cement or something you know i can still hear myself groan all of a sudden you're just going to like go with it and that's where i was when he said we're not gonna make it and that woke me up and i said oh yes we are too you know and you pray really hard the savage winds ripped unrelentingly over the smith heisler's home when they finally stop the couple emerge from their basement and into a war zone and i thought where's the car and my next thought was where's the garage the twister destroyed the couple's two-story home five barns dismantled five cars and killed their dog sugar the terror down there was the worst part the terror the smith heislers are lucky to be alive with estimated wind speeds near 400 kilometers per hour the f4 tornado easily destroyed their home but even the earlier f2 with winds estimated at 240 kilometers per hour was capable of ripping the roof off this home complex physics transform air into a lethal force a concept scientists are laboring to understand what we are trying to do is simulate the tornado as best as we can so we actually comparing the wind which we generate here with with the measurements made in the field and the match is pretty good saka's tornado simulator is the first of its kind in the world it uses dry ice to create a visual display of the wind inside a vortex his machine can produce tornadoes up to 1.2 meters in diameter and 2.4 meters tall it can reach peak wind speeds of 86 kilometers per hour when combined with scale models he's able to replicate damage much larger and faster tornadoes inflict on homes and other structures normally a portion of the roof fails and create a hole in the building which then the flow starts getting inside which then creates more load on the on the walls and eventually those walls start failing saka's experiments conclude that the destructive force of circulating wind in an f3 or stronger tornado is at least three times more powerful than straight-line winds since few structures in tornado alley are designed to withstand even an f1's winds this is stark proof that even the weakest tornado is capable of causing damage the residents of attica were thankful to have survived the fury of the 16 tornadoes that struck southern kansas but when a single f4 twister strikes a small texas town its bizarre behavior and surprising power threatens to destroy the entire city and later a mega tornado strikes a major american city something experts say will happen in 2004 a single kansas storm produced a swarm of tornadoes that ravaged homes destroyed property and terrorized hundreds but the power and damage of that outbreak was far surpassed by the stunning force and unpredictable behavior of a single texas twister pamper texas has had its share of luck the town has prospered since oil was discovered here in 1921 today 17 000 residents work the hard soil farming ranching and refining oil but the town's location in the texas panhandle is also its biggest floor this is tornado country on the afternoon of june 8 1995 pampers luck ran out randy stumblefield is a lifelong resident of pamper in his two years as sheriff he's seen his share of violence but nothing compares to what he's about to confront about four o'clock in the afternoon we received a call that there was a large tornado was building on the south side of the emerald highway just about a mile and a half from where we're standing now stubblefield grants his camcorder and rushes towards the twister i washed it building on the farmland on the north side of the railroad tracks and it just started building getting bigger and bigger meteorologist chuck doswell is also chasing and filming the pamper tornado the evolution of the pampa tornado with respect to the parent thunderstorm was very unusual in my experience i've never seen anything quite like it what does well sees is remarkable the tornado is almost standing still it's impossible to tell what's going on in there then suddenly the tornado makes a sharp right turn this on behavior stuns doswell tornadoes move in a particular direction because they're tied to the storm that's producing them and the storm that's producing the moves in a particular direction because it's embedded in a wind field which is pushing it in that direction but the pamper tornado isn't moving in the same direction as the storm after a series of sharp turns the twister loops almost 270 degrees around doswell these erratic and unpredictable movements make this a very dangerous tornado let's go and i am completely mystified as to what was going on with that storm then it started traveling north get everybody inside because this is one big sun and hit a industrial complex belinda wardrobe works in that complex with her father she isn't listening to the news i learned that there was a tornado outside the building when my dad came to the door of the office i was in and said belinda there's a tornado on the ground west of us i'm curious i said can we look at it and he said oh no we don't need to look at it we need to get under some cover belinda and her father die for shelter as the twister slams towards them you could hear the tornado approaching it was like a gyrating just a turning that just got gradually more intense and louder the lights began to flicker as the pressure was building and then the lights went out whenever you first start seeing the real debris the metal the rooftops and all that that's when it hit the first series of steel buildings in the industrial complex and then an explosion the vacuum just took me up off the floor and slammed me into numerous things and was pulling me backward like a ragdoll you're going to see some vehicles going into the air transport trailers and truck combinations now these units weigh probably 22 000 pounds empty these were sucked up and in the tornado and we're going around and around stubblefield and oswell are among the few to ever film a tornado snatching up three-ton trucks this is a massively powerful twister one that has belinda waldrop trapped in its ferocious grip when i was in it everything's dark and i just tried to keep my eyes closed to protect my eyes i kept talking to myself thinking well this is it and at that time i just had a feeling of helplessness because there's nothing you can do i mean there's no way you can stop it you know or make it go another direction or anything like that and it was just a sick feeling that dropped me out here into the parking lot and just dropped me on my back and i could see the cloud in the tornado it looked like a white ghost just going up and and taking off belinda's encounter with the tornado is over but randy's is just beginning when i realized that he was going to go into the city of pampa stubblefield jumps back into his car and races down the road directly into the path of the tornado one of my deputies gets on the air and says watch out you're too close you know you're too close when debris starts coming in the car with you i had my windows down and and the trash from circulation was coming into the car with me it's going into the city at this time it was headed right straight from the sheriff's office in the downtown section well i had at that time about 65 prisoners in jail and you know we had a big strong building but this big strong tornado the twister strikes pamper destroying or damaging 200 homes and 50 businesses most buildings in the industrial park are ripped off their foundations belinda is badly injured and in shock of course i was just stunned and numb i i really couldn't feel anything i felt like my legs were probably broken i couldn't get my bearings because there was no building there were no landmarks that i recognized at all and i was just taken back fearing the worst belinda desperately searches for her father he was draped over a motor he looked dead honestly he was limp and he wasn't moving i managed to scoot over close to him and started rubbing him he woke up and turned his head and you there was blood and you could just see this white eyeball just you could just terrified look and and i'll always remember that just stark and he immediately said help me up help me up and i i can't help you up i can't get up either emergency workers rush belinda and her dad to the hospital both are in serious condition five other residents also suffer injuries miraculously there are no deaths as the wounded begin their recuperation experts study stubblefield and doswell's remarkable footage to tumble a two or three ton pickup truck along the ground and then hoisted in the air this takes incredible wind speeds probably in excess of 150 miles per hour dave lewellen researches the strange and complex forces at work inside tornadoes in a tornado the wind is not just swirling around it's actually spiraling strongly inwards llewellyn believes that once an object like a vehicle is airborne it can be slammed to the ground by powerful center downdraft wings then held back skywards by updraft winds this brutal cycle renders the debris unrecognizable before it's finally spat out as a high-speed missile amazing that was four thousand six hundred pounds for into the crane scott schiff and his team at clemson university are studying the damage a tornado hurled car can do we're really testing this roof slab here and this was designed to be a shelter it's about 10 inches thick a solid concrete with a double mat of steel reinforcement so it's heavily reinforced it's really designed to be able to take large debris impacts three two one drop after multiple impacts the slab begins to crumble so after that last impact we now have a permanent deformation in the slab that rebar that's down into that bottom mat here started to yield under the load and we started to see some more concrete falling down below there to counter multiple impacts schiff is designing a steel mesh net to catch loose debris if that works it will be a huge step forward in tornado protection we have a terrific f5 tornado what we're looking for is that we are safe during the event and right after the event despite the pamper tornado's unpredictable movements and incredible power no lives were taken 608 kilometers away another texas town isn't so fortunate when a massive f5 twister turns tiny bits of dirt and wood into lethal weapons and later a mega tornado one that scientists believe could destroy a major american city [Applause] the powerful f4 pamper tornado tossed trucks destroyed buildings and threatened the lives of hundreds but just one notch up the vegeta scale an f5 twister turns into a killer its weapons specks of dirt and splinters of wood gerald texas was founded in 1909 located 64 kilometers north of austin the town never fully recovered from the decline of the cotton industry in the 1920s and 30s in 1997 a tornado threatened to wipe gerald off the map from the beginning the gerald tornado smacks of something strange on may 27th a supercell forms over central texas the gerald tornado is memorable for a couple of things one was it was a it formed in conditions that at the time we thought were very unusual the massive supercell lacks strong vertical wind shear an essential ingredient in typical tornado formation meteorologist bill gallis teaches tornado forecasting utilizing a virtual reality tornado simulator to get a tornado in nature you need to have really two things you need a very strong updraft or updraft and downdraft to help stretch the air in the vertical and you also need to have some source of spin present strong wind shear usually provides a tornado with its source of spin before gerald the conventional wisdom was that without strong wind shear you don't get violent tornadoes but the unusual atmospheric conditions over central texas are about to prove the conventional wisdom wrong dead wrong here the warm moist air rises so forcefully it generates a super strong updraft creating a very powerful and dangerous tornado as the skies blacken and the winds rage ladonna peterson and her eight-year-old son leave their mobile home for the safety of her mother-in-law's brick house i went outside and started watching the clouds outside because they were getting real thick real dark real heavy and all of a sudden i could hear in the distance because the wind had picked up the alarm going off in town ken adams doesn't hear the town alarm he's asleep and the dog woke me up and i could tell that dog was really scared i knew something was wrong but i don't hear well but i could feel it it was like a thunder that you couldn't hear you know but but you could feel it ladonna's sister-in-law and young daughter join her in their mother-in-law's home news reports place a tornado three kilometers away my sister-in-law and i went to a window and we could actually see the tornado in the distance but it was like it was just sitting there just turning not moving at all in fact the tornado isn't standing still its forward movement is clocked at a slow pace of 16 kilometers per hour but its internal wind speeds are reaching more than 420 kilometers per hour now a killer f5 it descends on the women's refuge then all of a sudden we felt the gust of wind hit the house we could actually see the asphalt being pulled up off the street up the road from us we were sitting there and i said god please don't take my family then we felt a big gust of wind hit the house and the bathroom door flew open and at that point we just started feeling like mud and stuff start coming in hey minutes later when ken adams walks outside to see why his dog is barking he comes face to face with a nightmare it was so big at the base probably a half a mile or three quarters of a mile that i didn't realize it was a tornado and by the time that i did realize that it was too late to go anywhere i ran to the house opened the back door and as i did the door flew out of my hands and the roof of the house came off [Music] i would sort of be picked up the house would fall on me again suddenly the tornado is gone the whole country looked like it was in a nuclear blast of some type when i first looked up i thought i was dead i mean i really did ken is wrenched back to reality when he's forced to take in the horror that surrounds him more than 300 head of cattle were killed or injured by the tornado many that survived had to be shot because of the extent of their injuries oh it was terrible there's about 300 acres over there and most of it you couldn't walk very far without smelling that old dead smell ladonna's family emerges from the rubble of their home and into a wasteland nearly every home in their subdivision is obliterated many of their neighbors are nowhere to be seen others are badly injured mrs lafrance was pinned under a tree and her daughter was laying in the mud and had some really severe injuries to her legs and her arms it was raining and it was she was saying it was hurting her hitting the open wound so the only thing i could find was a dirty blanket laying on the ground to cover up with just to keep the rain from hitting the wound so bad later we found out that mr lafrance had been killed in the tornado and the daughter had been crying through the whole thing wanting to know where her dad was 27 people died that day half were children entire families killed [Music] [Applause] as scientists study the general tornado several intriguing facts came to light the thing that the tornado itself was interesting for was that it was moving very very slowly it was large and it collected a lot of debris to where the high wind speeds associated with the tornado were there for minutes in locations rather than just for a few seconds the tornado traveled approximately 16 kilometers per hour significantly slower than the average 48 kilometer per hour twister another oddity was that most houses in the tornado's path were completely obliterated after much study experts found an answer physicist dave llewellyn's computer models illustrate their findings you can actually have thousands of tons of dirt in that debris cloud at any given time and that dirt can change the internal structure of the tornado as the gerald tornado passed over the open texas plane it picked up massive amounts of dirt slowing down the funnel's forward movement while increasing its destructive power i think down low that gerald tornado probably acted like a giant sand blaster llewellyn and others believe that instead of blowing apart homes with strong winds like some tornadoes the general twister destroyed structures via the massive force of windblown debris the gerald tornado was as ironic as it was tragic experts advise never to try and outrun a twister but some who died in gerald could have escaped the slow-moving storm in cars experts advise potential victims without storm shelters to hide in interior rooms like closets or bathrooms but some in gerald did exactly that and died anyway when their entire home was swept away still because no two twisters are ever the same experts advise that the best option is an underground shelter or safe room built to specific codes the general tornado changed the way experts watch for twisters they now view storm systems with low vertical wind shear as possible violent tornado producers but no amount of vigilance or insight could stop the deadliest tornado in us history from killing hundreds and later a mega tornado unseen in modern times threatens millions the general twister killed 27 people while changing the way experts keep vigil for potential tornado-producing storms but there was no way to prepare for the deadliest tornado in us history a brutal f5 that tore through three states killing hundreds on march 18 1925 a single tornado slaughtered 695 people in missouri illinois and indiana the behemoth f5 blasted a 322 kilometer path of unstoppable annihilation that lasted for hours survivor accounts are chilling the air was filled with 10 000 things boards poles whole sides of little framed houses in some cases the houses themselves were picked up smashed to the earth and living beings too a baby was blown from its mother's arms children all around me were cut and bleeding they cried and screamed it was something awful the destruction was of mythic proportions primarily because the killer struck an extremely vulnerable population people had very few ideas about how to deal with tornadoes the country was largely rural instead of mostly metropolitan and they had essentially no way to communicate with each other the town of murfreesboro where more than 100 people were killed actually was hit more than two hours after the first fatalities from the tornado and people wondered why hadn't any word gotten down downstream down the telephone lines or telegraph lines that something was coming in 1925 several million people lived in small rural towns throughout tornado alley today tens of millions call it home modern communication means better warnings but evacuating a major city before an f5 strikes is still impossible on may 3 1999 the people of oklahoma city faced the worst f5 in modern history the mather 1999 tornado that went through more in southern oklahoma city was one of the most damaging in the history of the united states no matter how we look at the data late in the afternoon of may 3rd 1999 forecasters in oklahoma carefully track multiple supercell storms and then the tornado reports that begin flooding in at home with her eight-year-old son dana grimm watches the local news we had been watching the coverage for hours he said it just kept building momentum getting bigger and bigger and if you were above ground you weren't going to make it the storm system is intense complicated and growing weather trackers watch in war and shock as multiple storms produce multiple tornadoes large tornadoes very large tornadoes seemed like just about every thunderstorm cloud that formed eventually produced a tornado at some point and there were times when you had the main tornado happening and then we had what we call satellite tornadoes that would rotate around it they're completely separate tornadoes within the same storm system at about 6 25 p.m a large tornado touches down just outside amber oklahoma doppler radar records its wind speed at 512 kilometers per hour the fastest twister ever documented this is a monster and its hurtling towards dana grimm's home and they had said that it was a mile wide and just ferocious and it was just destroying everything in its path [Music] with a giant wall of howling wind just 1.6 kilometers away dana and her son hide in the closet i remember my son he was screaming and crying he said well are we going to be okay i said we're going to be fine he said what do we do and i said we pray dana's fear turns to panic when she hears the tornado strike there was kind of a high pitched squeal to it and then of course the sound of everything the windows just blowing out the house was shaken we could hear the the beams in the roof breaking the walls just lifted up and we could feel really cold air rushing underneath [Applause] and within seconds of that the house just blew up i couldn't breathe i had sucked in so much dirt that i couldn't even breathe anymore i thought this is it and i remember just praying that god if this is it i'm ready on the brink of death the fierce tornado spares dana's life by lifting her out of the suffocating dirt when it slams her back to the ground she's paralyzed with fear and i realized then that i didn't have my son so i started screaming for him and he came running over and it was really it was just a miracle of god because we were both barefoot he came running over to me did not have one puncture wound on his feet the f5 continues towards the center of oklahoma city crossing major highways filled with rush hour traffic as the tornado hurtles towards them some people panic they abandon their cars in a desperate attempt to find shelter for a few that decision has fatal consequences three people seeking refuge under freeway overpasses are killed by debris and the sheer force of the wind stranded cars block escape routes for many others shields boulevard in oklahoma city essentially became a huge parking lot and it blocked people from being able to escape the tornado by the time the f5 dissipates 40 people are dead and nearly 700 injured my wife worked in the hospital in norman that night and uh she worked in the emergency room they were swamped of course she saw some really horrific injuries people came in covered with splinters of wood looked like pin cushions so much wood awful things many survivors suffer multiple painful wounds from being impaled by debris cheryl brown studied the injuries and deaths in oklahoma there were also injuries that were related to debris being embedded inside the body all the way from small splinters to very large objects such as two by fours many survivors suffered debris related injuries because the tornado destroyed so many homes spewing countless shards of wood and other material into the air the oklahoma twister leveled nearly three thousand houses and structures two one fire 73 miles an hour chef and his team at clemson university fire two by fours at more than 160 kilometers per hour into a variety of structures to represent the damage done during a tornado i think that the the public understands that tornadoes are very dangerous what they don't understand is that in typical construction they have very little protection against those types of events when debris strikes a home it does far more damage than simply making a hole in a wall or window fire it gives the tornado a point of injury once inside inflowing air can rip apart walls and tear off the roof the home then becomes part of the tornado's arsenal further fueling the funnel with debris and making it even more destructive this type of construction is very typical for a residential you know brick veneer in front of a wood frame wall the missile's gone all the way through the wall cavity most people that have this type of house would be vulnerable to an f5 tornado fire schiff's experiments determined that for a home to withstand the deadly onset of debris the brick veneer must have an eight centimeter thick backing of concrete so this wall here would be suitable for a shelter to resist tornadoes most homes in oklahoma city were brick veneer with wood frames this common construction coupled with the sheer number of homes in the tornado's path increased the debris field exponentially dana grimm survived with a broken back her son with a puncture wound to his chest i truly believe that the reason that i was throwing talks if i had not been picked back up and thrown again i would have suffocated because i could not breathe in anymore ten supercell storms spawned 70 tornadoes that spring day including the f5 that cut a 24 kilometer path over interstate highways and devastated several suburbs of oklahoma city it was sad i think there were 14 in our own housing edition that died and it it's a miracle of god that we didn't the oklahoma tornado caused more than a billion dollars in damage the costliest tornado in us history complete and total devastation the homes that you see over here now were completely gone it was it was a rubble pile if you had been in the open it would not have been a very pleasant place to be things would have been much worse if the tornado had veered just 16 kilometers to the west striking the heart of downtown oklahoma city even so the war oklahoma tornado and its companion twisters rank as the most deadly and destructive outbreak in modern history they would be far surpassed by an f5 striking a major american city that would be a mega disaster one experts warn could happen every year major u.s cities and tornado alley play a game of russian roulette with massive twisters that wreak havoc there in 1999 oklahoma city lost the game when a giant tornado killed 40 people injured nearly 700 and racked up costs of more than a billion dollars only sheer luck kept the tornado from striking downtown researcher scott ray knows the next major city to be struck by an f5 may not be so fortunate dallas is overdue for a large violent class tornado dallas texas is a boom town sprawled along the southern boundary of tornado alley it's one of the largest and fastest growing metro areas in the us with more than 5 million residents and 600 corporate headquarters dallas is 10 times larger than oklahoma city i was shocked a bit when i saw some of the aerial footage of oklahoma city the amount of damage that had occurred in that was pretty amazing rain assists local governments with planning for hazards especially threats from tornadoes to help dallas prepare for a possible mega disaster he has modeled over 60 different scenarios of how the dallas region would be affected by a violent tornado for reasons of credibility it was very important that we look at an event that actually had occurred somewhere else so we took the the event at oklahoma city basically because the data was very good for that particular event and we could transpose it by just moving those same geographical characteristics of the tornado on top of the geography of dallas fort worth so we got to see it kind of from our own perspective ray and his team painstakingly overlaid the exact path taken by the oklahoma tornadoes over the dallas fort worth area a mega disaster unfolds when oklahoma's f5 tornado rampages through downtown dallas it would easily be the worst damaging tornado event that we have had to date in the u.s ray's nightmare scenario begins as a supercell storm forms over north central texas a 160 kilometer per hour tornado and f3 touches down in a dusty field 10 miles southwest of dallas its first target is the suburb of crocker hill while packing winds in excess of 320 kilometers per hour cars are tossed aside buildings are decimated the tornado continues northeast unrelenting in its assault on thousands of homes the twister's internal wind speeds rise past 400 kilometers per hour turning it into an f5 fueled by tons of debris the giant tornado slows as it descends on the busy freeway a clogged highway holds a heck of a lot more people than one that is moving comfortably and the other problem that you have is where do you go panic ensues as many abandon their cars creating a traffic jam that traps thousands the 443 kilometer per hour winds effortlessly swat cars off the highway anyone hiding under an overpass is vulnerable to flying debris and violent winds cars snatched up by the powerful updraft winds are spun around inside the giant baltics then shot out creating a dangerous hazard for anyone in their path next the deadly twister approaches downtown dallas dozens of skyscrapers and tens of thousands of people crowd the city giant glass windows shatter marble and bricks are ripped off buildings a deadly shower of glass and other debris rains down onto the crowd below most of the skyscrapers in the dallas fort worth area are predominantly covered with glass on the outside and that's not very durable but the amount of damage from getting wind and broken glass spread out through a downtown area is going to be pretty dramatic a packed commuter train sneaks through the city it swept off the tracks and slammed into a skyscraper killing hundreds of the train and office buildings there's little doubt that debris would be uh probably the largest generator of damage in the metroplex and it's basically because there's so much of it that can be generated and you name it it could be wood bricks gravel just about anything you can imagine can become a projectile and and with almost unlimited supply the tornado continues north leaving the wreckage of downtown dallas behind him tornadic winds more than 500 kilometers per hour now descend on the suburban landscape of lakewood the 92 000 people living here have had up to 20 minutes to seek underground shelter a seemingly reasonable chance for survival but like the gerald texas twister those hiding in closets or bathrooms can only pray the worst tornado in history slowly drifts skyward and dissipates the war zone behind it is 61 kilometers long dallas is devastated i don't think there's there's any way to really sugarcoat an event it's going to be difficult to deal with regardless there's going to be a lot of damage there going to be a lot of people that need help total damages approach five billion dollars tens of thousands are homeless and scores injured the death toll is unknown fatalities are difficult to really quantize because they involve people making decisions and there are good decisions that can be made bad decisions we don't know what decision they're going to make the best decision city planners can make is to prepare with multiple underground shelters rehearsed evacuation plans and a vigilant public but even that won't likely be enough i think it would pretty much be impossible financially to build a city that could really survive violent class tornadoes or you know any scenario like that with increasing populations in major metropolitan cities throughout tornado alley science is in a life or death race against time to understand one of mother nature's biggest secrets in an ideal world we'd have radar or other instrument measurements on every tornado that occurs in the practical world that we live in that's just not going to happen okay this storm in the next hour is going to produce this type of tornado we're just not there yet and it's hard to say when we'll be there we've certainly got a ways to go given the limited ability to predict tornadoes there is a very real cause for concern most people think about disasters as very random events that can't happen to them and i think that holds true with tornadoes as well if you wait long enough something resembling the worst case scenario is going to happen eventually until science learns more about these brutal forces of nature the only thing that can be done is to prepare before a mega disaster strikes when the earthquakes all hell breaks loose they strike with lightning speed a huge fault of destruction these forces baffle experts who are on a desperate mission to predict when and where the next big one will hit with each earthquake you have things that you didn't predict before we'll circle the globe examining significant earthquakes of our time each more powerful than the last each with its own compelling mysteries each propelling us towards a projected mega disaster a monster quake that could rock our world [Music] earthquakes are one of the most destructive and unpredictable forces on the planet without warning solid ground cracks shifts and buckles threatening anything in its path it's estimated that several million earthquakes shake the planet every year most are barely detectable tremors but at least once a year somewhere on the globe a major event strikes most earthquakes are created by movements of titanic slabs of the earth's crust called tectonic plates enormous pressure builds as the plates strain against each other when plates slide past each other a strike-slip earthquake forms when plates collide head-on and one slides under the other a thrust earthquake occurs in both cases the earth's crust tears and snaps releasing a giant burst of seismic force the amount of energy released by an earthquake is known as its magnitude the higher the magnitude the more energy released an earthquake of magnitude 8 or higher releases as much energy as a billion tons of tnt or 67 000 hiroshima bombs earthquakes destructive energy has cost almost 8 million lives in the last 1 000 years the fatality rate is rising as populations in high risk areas increase dramatically and it's kind of an inevitable shift as people cluster more and more the largest cities continue to grow larger and larger today there are 17 cities jammed with more than 10 million people 140 other metropolitan areas have populations topping 2 million more than half of these are within striking distance of a major fault line placing hundreds of millions directly in the line of fire a lot of times we are our own worst enemies in terms of where we build and how we build these cities it's only a matter of time before another city is hit by a devastating earthquake to prepare for the inevitable future it's essential to learn from the past october 17 1989 san francisco california for 15 horrific seconds the city by the bay is rocked by a magnitude 6.9 earthquake the epicenter is near a mountain in santa clara county called loma prieta close to the mountains suffer serious damage the ground splits open in huge gashes hundreds of homes are thrown off their foundations and small communities are ripped apart the two people were dead but bizarrely the greatest devastation and loss of life is 97 kilometers to the north in oakland and san francisco the quake brings down a section of oakland's cypress expressway turning a busy freeway into a graveyard oakland firefighter lorenzo freddiani is one of the first to respond it was a horrible scene it was such a large-scale disaster seeing huge pieces of the freeway on top of cars fires beginning to erupt everyone just yelling and screaming for help freddiani and other rescuers race to find survivors they fear the worst that thousands are dead under the shattered remains of the expressway this was at five o'clock approximately this is its peak time there should be bumper to bumper traffic so when i saw the cypress unfold in front of me all i could think about was how many thousands of people would be dead but amidst the horror there is a life-saving stroke of luck the earthquake hit as the two local baseball teams the san francisco giants and the oakland athletics faced off in the world series millions are watching the game and traffic is much lighter than usual the fact that we had the ball game between the two bay area teams easily saved thousands of lives as rescuers desperately trying to free those trapped on the cyprus expressway another disaster unfolds across the bay nearly 200 buildings in the marina district are severely damaged or completely destroyed fires started by broken gas mains add to the damage and panic stunned residents flee into the streets but even as the marina suffers catastrophic damage neighborhoods surrounding it escape almost unscathed seismologists like jack boatwright struggle to understand the quake's selective destruction the ground motion and damage in the marina was a surprise not just to lay people it was also a surprise to seismologists the earthquake seemed to defy logic it targeted two specific areas 97 kilometers from the epicentre leaving most of the bay area untouched boatwright and his colleagues set out to solve this mystery by going back to basics when a fault ruptures spherical waves of energy are released traveling through the ground until they reach the surface like any other kind of wave they can bend reflect or join together to make bigger waves oakland and the marina district were unlucky enough to be hit by a seismic double team two sets of waves that joined together one said travelled directly from the earthquake center to the surface another traveled deep into the earth then bounced off the boundary between the solid crust and the molten layer beneath it the reflected waves reached the surface 97 kilometers away from their source directly under oakland and the marina district this seismic double whammy was bad enough but it became much worse when combined with a fatal mistake made by the city's forefathers a hundred years ago this land didn't exist as the bay area rapidly expanded stretches of ocean became beachfront property the shallow edges of the bay were filled in with sand and debris the difficulty is these very fine and clean sands when an earthquake occurs and you start shaking them there's really nothing binding the sand together it becomes actually a liquid liquefaction is a deadly side effect of many large earthquakes as solid ground turns to liquid roads are destroyed buildings topple and underground pipes rupture liquefaction severed a gas main in the marina igniting an inferno the total cost of the quake was huge 63 people died four thousand were injured and 20 000 structures were damaged or destroyed for seismologists the 6.9 loma prieta quake was a brutal wake-up call they were surprised by the reflection of seismic waves that struck the marina district and oakland with each earthquake you have things that you didn't predict before every earthquake is in fact a learning experience but the 1999 loma prieta quake was not the worst to strike san francisco the same side effects of liquefaction and fire killed thousands when a much bigger earthquake struck destroying most of the city by the bay [Music] [Music] around the turn of the century san francisco was actually the premier city on the west coast of the united states the city featured luxury hotels and modern high-rise buildings but in 1906 many came crashing down the earthquake occurred about 5 12 in the morning on april 18th and when it occurred it essentially occurred without warning a loud roar jolted thousands out of their beds seconds later a giant shockwave hit the city shaking buildings to their foundations the west coast's economic and architectural center lay in ruins at the time seismology was in its infancy and the quake's cause was not well understood we now know the city was caught in the middle of an ancient battle between the pacific and north american tectonic plates an infamous war zone called the san andreas fault these mighty slabs of crust are scraping past each other directly beneath san francisco when sections become locked together enormous pressure builds up and is released as a strike slip earthquake in 1906 435 kilometers of the fault ruptured a magnitude 7.8 quake released eight times more energy than the 1989 event the first and fastest waves released by any earthquake are primary or p waves they act like a sonic boom shaking the ground and rattling windows a few seconds behind are the secondary or s waves these carry most of the earthquakes energy and are the most destructive kind of seismic wave in san francisco the s waves tore huge gashes on the earth and ripped apart building foundations like paper but it was another side effect of the earthquake that sealed the city's fate liquefaction of the ground severed gas and water mains and san francisco began to burn without a water supply the fire department stood by helpless as the city burned to the ground the descriptions of the fire are they actually refer to this as a fire storm and in a firestorm the heat is so intense that it actually sucks in air the fire raged for three days incinerating 10 square kilometers destroying more than 28 000 buildings and leaving a quarter of a million residents homeless more than 3 000 people were killed the 1906 event proved that an earthquake's complex side effects can be more devastating than the quake itself 80 years later a bigger earthquake crippled the city 45 times larger than san francisco the key culprits a totally different seismic side effect combined with disastrous city planning but even that quake is dwarfed by a potential mega quaint an event of enormous power and consequence the san francisco earthquakes of 1906 and 1989 showed how reflection and liquefaction can have tragic consequences in 1985 one of the largest cities in the world was crippled by an earthquake with even stranger and more unpredictable effects it proved that where you build a city is as important as how you build it mexico city is one of the world's largest cities with a current population of more than 20 million the metropolis sprawls across a mountain valley in the center of mexico it's a city of non-stop activity its massive population busy day and night on september 19 1985 dawn breaks on a typical autumn morning millions of people face the new day suddenly the earth begins to rise and buckle a magnitude 8 earthquake strikes the city the epicenter is off mexico's west coast it unleashes six times more destructive energy than the 1906 san francisco quake hundreds of multi-storied buildings disintegrate into rubble thousands of others are severely damaged i didn't know what was happening your mind is racing a thousand miles per hour you don't know if you're already dead the city struggles to cope as phone and electricity lines are severed emergency services overwhelmed and millions left to fend for themselves three of the city's largest hospitals are severely damaged adding to the chaos and casualties one of the most horrific scenes is at the nuevo leon a 15-story apartment building of the 1800 people who lived here more than 600 were killed quartermaine avarka is a stunned witness as the nuevo leon falls victim to the earthquake's rage i recall it like a nightmare because this huge structure so solid for us in those moments it was collapsing like if it was made of paper like a model that invisible hand was pushing down quota make and dozens of his neighbors rush to the demolished apartment building and with their bare hands begin a desperate struggle to rescue survivors there was a survivor that was trapped by the debris we couldn't move the concrete above him it was also heavy i was holding the right hand of this man trying to encourage him he was complaining this is so painful it hurts and he died the death toll is estimated at anywhere between nine and thirty five thousand the true number may never be known why was this mighty city victim to such devastation mexico city is in the center of the country hundreds of kilometers away from the earthquake's epicenter and why were some areas practically annihilated while others were left untouched for seismologists like cena lomnets this disaster would change their understanding of seismic waves there are various surprising factors that intervened to cause this particular earthquake to be a disaster the quake was triggered by movements of the cocos plate which collides with the north american plate of mexico's west coast unlike the san andreas fault where two plates are sliding past each other mexico is the scene of a tectonic head-on collision called a subduction zone normally one plate slides smoothly under the other but when a section becomes stuck enormous pressure builds up in the rock on that fateful morning the pressure finally becomes too much a section of the cocos subduction zone rips apart blasting a massive shock wave of seismic energy towards mexico at thousands of kilometers per hour during most earthquakes the greatest damage occurs close to the epicenter this one is different coastal areas suffer some significant damage but mexico city located 322 kilometers inland bears the biggest grunt of the earthquake bizarrely most of the city is barely damaged while small specific areas are almost completely destroyed buildings between 6 and 15 stories high suffer the most shorter and taller structures in the same block survive virtually unscathed to solve the perplexing mysteries lumnitz and his colleagues searched directly beneath their feet mexico city has a rather unusual location for a large city 700 years ago what today is mexico city was a lake the aztecs built their capital city tenochtitlan on an island in the middle of the lake it was a massive complex of canals and causeways with a structure as complex as any european city at the time when the spanish conquistadors captured and totally destroyed tenochtitlan they filled in the lake and constructed their own city directly on top of it centuries later this turned out to be a very bad idea the sedimentary there on which the downtown area is built is a layer of very soft clay it's practically a jelly it's almost water this ancient lake bed holds the key to the earthquake's strangely selective damage patterns over the first three days after the earthquake we realized that severe damage structural damage had only occurred on the former lake area the layer of soft lake bed was not just unstable it acted like a seismic amplifier trapping seismic waves and actually boosting their strength just like jelly will keep wobbling long after you shake it the layer of mud under mexico city continue to shake for four minutes after the earthquake this is the major cause of the disaster but that didn't solve the mystery of why buildings between 6 and 15 stories suffered the most damage the answer came in the form of another destructive combination of seismic waves and loose sediments a phenomenon known as resonance every object has a certain frequency that makes it resonate if a singer hits the right note they can shatter a glass just by subjecting it to its unique resonant frequency even a large object like a high-rise building can resonate depending on its size and structure there is one energy frequency that will make it vibrate by incredibly bad luck the seismic waves trapped and amplified by the layer of mud under mexico city were exactly the right frequency to make six to 15 story buildings resonate the buildings began to vibrate shaking themselves to pieces others smashed into their neighbors like battering rams these freak circumstances doomed mexico city many important facilities such as hospitals and schools were in the fatal size range singled out by the earthquake's fury the mexico city quake was a tragic example of the dangers of building on soft or reclaimed land the unstable soils amplified the quake's effects and unleashed complex and deadly patterns of resonance today buildings cannot be constructed on the unstable lake bed building codes and civil emergency plans are enforced to help prevent future disaster the people of mexico city know they're at risk from earthquakes but millions of others live in striking distance of rare mysterious quakes and don't even know it and we're moving closer to an even bigger quake a potential scenario that will combine liquefaction fire and other deadly side effects in a brutal mega disaster san francisco and mexico city both fell victim to earthquakes spawned by the volatile boundaries between tectonic plates half the world's large cities are within striking distance of major faults like this but the other half are not necessarily out of danger there is a totally different type of earthquake these rare rogue events strike seemingly from nowhere ravaging areas thought to be immune to earthquakes [Music] january 26 is india's independence day but in 2001 the celebrations are forgotten when a massive earthquake strikes the western province of gujarat the 7.7 quake destroys the historic city of buge along with many other nearby towns and cities 20 000 people are killed and a million homes lost or damaged 200 villagers are wiped from the map paul bowden is a memphis tennessee-based seismologist who traveled to india to study the quake what we saw was an immense amount of devastation the human toll was incredible it was a horrible place to actually be doing the work that we had to do for scientists like bowden the most stunning aspect of the quake is not the scale of the damage but the fact that it occurred at all according to the theory of plate tectonics this earthquake should not have happened central asia is no stranger to deadly plagues over a billion people live close to a massive tectonic collision as the indian plate plows head on into the rest of asia the himalayas the largest continental mountain range on earth are the crumpled wreckage of this collision [Music] this volatile plate boundary has spawned numerous deadly earthquakes the 2005 kashmir quake killed almost 80 000 people in pakistan and northern india it was magnitude 7.6 not huge but powerful enough to flatten hundreds of thousands of buildings but bouge is 200 kilometers away from the dangerous himalayan plate boundary large earthquakes shouldn't happen here but there's these these rogue five percent that happen away from plate boundaries and we don't have a very good understanding of why what drives these kind of earthquakes these mysterious rogue disasters are called intra-plate quakes the 2001 bouge earthquake was an important opportunity to study one of these rare events but bowden and his team had a more urgent reason to travel from memphis to india the largest intra-plate earthquakes in history happened right in their own backyard in the winter of late 1811 and early 1812 the midwest of the united states was torn apart by a swarm of massive earthquakes they were probably bigger than any quake to hit california and are named after an ordinary town with an extraordinary secret new madrid the magnitude of each can only be estimated since seismic recording instruments didn't exist but there is no doubt they were huge the first estimated at magnitude 8 hits on the 16th of december 1811 houses and buildings are torn apart entire forests are wiped out enormous cracks split and tear the earth the placid mississippi becomes a raging torrent of rapids and waterfalls but this was only the beginning a month later another giant quake estimated at magnitude 8 tears the frontier town of new madrid missouri to pieces two weeks after that a third magnitude eight quake strikes over the next two months almost two thousand smaller trimmers strike the effects are felt throughout the entire eastern half of the united states in new madrid in the middle of the plate to have a large earthquake a huge earthquake is astounding and then to follow it up with two other events that were as large or larger just incredible this incredible series of earthquakes seems to have come from nowhere this is the flat stable center of the north american plate it's supposed to be safe from large earthquakes real foot lake 24 kilometers from new madrid is famous for its fishing but seismologist roy van arsdale hasn't come for the largemouth bass for him real foot holds the key to unlocking the mystery of the new madrid quakes 200 years ago this lake didn't exist well this serene swamp and lake area was rocked severely during the winter of 1811 1812 in a series of three giant earthquakes it was the third one in march that is responsible for the formation of this lake realfoot lake's peaceful appearance is deceptive beneath its calm waters scientists have made an earth-shattering discovery there's microseismic activity meaning little earthquakes are occurring all the time out here so there are seismometers planted in the landscape around us measuring recording these earthquakes deep under real foot lake and new madrid is a mysterious fault system that spawned the huge earthquakes of 1811 1812 it continues to generate small earthquakes today but this discovery raises even more questions if the new madrid fault is not a plate boundary then what is it the answer to that lies far away in ethiopia this is part of asia and africa's great rift valley a fault system that stretches 4 800 kilometers from northern syria to mozambique the earth here is splitting apart and bleeding molten rock a tectonic plate is being torn in half and pushed apart a process called rifting 500 million years ago this almost happened in the peaceful plains of the midwest a surge of magma spewed up from the molten interior of the earth eating through the crust beneath the ancient midwest but before the plate was completely split the magma retreated leaving behind vast cracks in the earth's crust as pressure builds up on this fault system it's released as massive earthquakes a similar failed rift has been found near the city of bourge in india the buried rifts under bouge and new madrid solved part of the mystery but there are still many things scientists don't understand about intraplate earthquakes they have no idea what triggers these rogue disasters or where they will strike next we really don't have a good working model for what drives these intraplate earthquakes this is still quite the mystery and seismology geology that a number of us are working on and we just don't have an answer to that right now in 1811 and 1812 the new madrid earthquake struck sparsely populated areas today millions of people living in cities like saint louis and memphis are within striking distance of the new madrid fault system if it wakes again the human and economic toll will be devastating it would be foolish to think that it couldn't happen again that it's over there's nothing there's no scientific evidence that whatever is giving rise to these earthquakes has gone away the new madrid quakes were the largest intra-plate earthquakes in history but they pale in comparison to a massive tectonic rupture that ripped through chile producing the largest earthquake on record and even that catastrophe is not the worst case scenario experts believe a giant earthquake lies in weight one whose shock waves will ravage a nation and shake the entire planet there is one earthquake that towers over all others one so massive it changed the shape of a nation and killed people half a world away this is a staggering event that rates as the largest on record in the small chilean town of mao jin life is quiet and simple its 1500 residents depend on the sea and the soil to survive but in 1960 both elements conspired to decimate this peaceful place juana lopez was eight months pregnant when her world was torn to pieces i was at my sister's house and felt a movement immediately i realized it was an earthquake [Music] was also caught by the earthquake's violence we couldn't stand up we had to sit down and hold to our fins but if instead we're moving like this then the earth has started to open but the shaking in margin is just the beginning a massive catastrophe is spreading across chile killing thousands and shaking the entire nation to its core 161 kilometers off the chilean coast the small dense nazca plate slams into the much larger and lighter south american plate creating a subduction zone this is far more dangerous than the one that affected mexico in 1985 because here it runs the entire length of the continent on may 22nd 1960 the nazca subduction zone spawns the largest earthquake ever measured by scientists a massive magnitude 9.5 the amount of energy unleashed is equal to 32 billion tons of tnt or more than 2 million hiroshima bombs the intense seismic waves tear apart cities caught in their path buildings topple the ground turns to liquid landslides sweep down mountain slopes and cliff fronts collapse into the ocean the city of aldivia close to the epicenter of the quake is besieged almost half the city is reduced to rubble but this is just the beginning the fault rupture sets in motion a chain of events that ruins lives for generations and permanently scars the landscape today valdivia is once again a thriving city a strategically important point at the meeting of three rivers but take a closer look and there are secrets beneath the water mysterious streets that plunge into nowhere drown foundations and ghost-like ruins along the river's banks the 1960 earthquake did far more than shake things up it forever changed the shape of the land itself this ruined landscape is the victim of a side effect of the massive chilean earthquake called subsidence the levia's fate was sealed hundreds of years before the quake for centuries pressure built up along the boundary of the two great tectonic plates off chile's coast the south american plate began to slowly bulge upwards under the strain when the fault ruptured in 1960 the strain was released on the south american plate it snapped back to its natural shape lowering a vast swath of land two and a half meters for the people of valdivia this is a disaster that will last for generations most of this area before the 1960 earthquake used to be pastures high quality pasture the ground drop at two meters down and now the tides uh cover every day this this land so there was a huge damage on the economy of these people here because they lost the soil the better soil of the area over 200 000 square kilometers of chile's coast subsided after the earthquake but incredibly even this was not the most deadly part of the day they said we need to be prepared because the sea is coming in the tsunami is coming and we have to climb up the hill just 15 minutes after the massive quake a series of giant earthquake generated tsunami waves slam into the coast some are 18 meters high from her vantage point on the hill above mao jin juana watches as half the town is washed away the waves were coming in trying to imprison us we heard another wave coming starting to move the houses that were on the shore making them hit one another it was a terrific noise a noise that scared us but nelly gallardo had no time to get to safety she was caught by the full fury of the waves as the wife was advancing trees and other things were disappearing in its path i climb up into some trees but when the second wife came the trees were not strong enough to hold us so i jumped onto a log and try to hold on and keep my face out of water then a boy climb on to the lord too 122 people from mao jin drowned that night but somehow nelly survived the giant waves wreaked havoc far beyond chile they radiated out from the fault rupture striking other unsuspecting pacific locations 15 hours after the earthquake struck the tsunami reached hawaii the port city of hilo was devastated and 61 lives lost seven hours later the tsunami hit japan killing 122 people the philippines and the west coast of the united states also felt the waves of destruction that day when it was all over the great chilean earthquake killed 2000 and left 2 million homeless it remains the largest earthquake on record but records were made to be broken scientists believe another giant earthquake lies in chile's future one that could be much much worse [Music] the evidence pointing towards a mega disaster lies on a remote section of coastline in southern chile this was once a big forest until the 1960 earthquake and tsunami devastated the area and left only twisted stumps to the trained eyes of geologist marco sisternas this deserted beach holds vital clues to chile's seismic future the 1960 event wasn't a unique event although it was a giant it wasn't unique in this outgroup you can see there is a soil a buried soil here this is 1960 soil covered by a tsunami sun layer here and below that you can find another soil corresponding to the 1575 earthquake along this coast there is evidence of another dozen earthquakes that ravaged the area in the last 2000 years so it is certain that in the future another earthquake giant earthquake is going to strike central chile when it strikes it will be an ultimate disaster an event that will [ __ ] the country and send shockwaves around the entire planet in 1960 the biggest earthquake ever recorded rocked chile thousands died and the landscape of the country changed forever but scientists believe a far more destructive quake could be on chile's horizon don windler is an expert in modeling disasters of the future using data from the giant 1960 quake and input from some of the world's leading seismologists windler and his colleagues have created sophisticated models of potential earthquakes in chile including the ultimate worst case scenario there's no stopping the nazca plate from going underneath south america we will continue to see large events over time in chile it's just a fact of life the massive 1960 earthquake struck in the center of the country where the population was relatively light but if the nazca fault ruptured further north near to chile's largest cities a major catastrophe would result we're going to expect to see a lot more economic loss a lot more casualties resulting from this event [Music] valparaiso is one of chile's major ports and home to its navy and houses of parliament the city sits in an amphitheater facing the ocean most of its 270 000 inhabitants live on the steep hills above and are carried to their homes by unique machines called funiculars just up the coast from valparaiso is the tourist resort of vina del mar famous for its beaches and luxury hotels are both part of chile's most valuable stretch of land if hit by a major earthquake the nation would be ravaged just that one area from valparaiso across the country through santiago metropolitan area contains over 50 percent of the property value for the country of chile and any kind of event that has significant serious damage to that area is going to have repercussions to the economy of the country wendell's nightmarish scenario begins 27 kilometers under the earth and 80 kilometers off the coast in the collision zone between the nazca and south american plates a stress point snaps starting a chain reaction more than 1400 kilometers of the subduction zone rip open like a zipper [Music] massive seismic shock waves spread from the rupturing rock the primary waves speed out at 29 000 kilometers per hour the arrival of the p waves and valparaiso feels like a long sonic boom windows and buildings shudder some of the p waves shoot up into the atmosphere emitting a frightening roar the secondary waves follow carrying most of the earthquakes energy some surface waves shake the ground from side to side twisting railway lines and shattering concrete structures buildings are shaken from their foundations unstable areas of the cliffs surrounding valporaizo collapse taking many buildings with them below in the port sediments amplify the seismic energy prolonging the shaking and the destruction liquefaction ruptures gas mains water pipes and vital communication links in addition to the deadly seismic waves the earthquake rupture releases pressure on the south american plate it pushes forward and flattens areas of the coast sink two meters entire structures collapse and flooding is rampant fires caused by broken gas mains rage out of control as the city lies paralyzed and in ruins the biggest killer of all is about to strike as the south american plate is released and flicks upwards it pushes up an enormous wave of water 967 kilometers long gravity quickly pushes it back creating a massive wave a tsunami one side of the wave rushes towards the coast of chile it takes just 10 minutes to reach vina del mar it hits the already besieged city with a 12 meter wall of ocean that smashes across the city thousands more lose their lives the city is devastated but the giant earthquake's deadly reach extends far beyond chile the same tsunami that pulverized vineyard el mar speeds across the pacific for thousands of kilometers hours after the quake huge waves strike new zealand hawaii and japan the west coast of the usa and the philippines will also be hard hit chile's mega earthquake is now a global disaster taking the 1960 earthquake this massive magnitude 9.5 and moving it closer to valparaiso and santiago is something that's not likely to happen anytime in the near future it's highly unlikely but at the same time given what we know about chile's tectonics and its past history it's very difficult to exclude that from saying that it can't occur chile's mega disaster will probably not happen within our lifetimes but scientists believe a major city will be struck by a devastating earthquake we're setting ourselves up for larger catastrophes should an event occur near one of those cities experts agree that while it's impossible to prevent an earthquake it is possible to prepare for one there are really many things we don't know about earthquakes but we do know one thing the way to avoid disasters is to be prepared for them when there is no surprise there is no disaster danger is that if we're not prepared if we don't prepare our cities for the hazard that exists there'll be hell to pay half the world's population now lives in cities placing hundreds of millions within striking distance of an earthquake for all of them the clock continues to tick on these giant underground time bombs

Channel: Spark

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Keywords: volcanic eruption footage, World's Deadliest Volcanoes, volcano eruption footage, volcanic eruptions, volcano eruptions, Nevado del Ruiz, volcano eruption, Mount Pinatubo, Mount Pelée, Mount Tambora, Thera, Eyjafjallajokull, Krakatoa, volcano event fortnite, volcano eruption fortnite, Mt. Vesuvius, Mount St. Helens, Mauna Loa, Technology, science explained, Science, Spark, science experiment, science photography, volcano, magma, earthquake, yellowstone, supervolcano, natural disasters

Id: Jm3EPmKFO9o

Length: 201min 40sec (12100 seconds)

Published: Fri May 06 2022