0:00:02 > 0:00:04My name's Steve Backshall.
0:00:06 > 0:00:09And this is Deadly Pole To Pole.
0:00:10 > 0:00:11Oh!
0:00:12 > 0:00:14From the top of the world to the bottom.
0:00:14 > 0:00:15Whoa!
0:00:15 > 0:00:17Deadly places.
0:00:17 > 0:00:18Deadly adventures.
0:00:18 > 0:00:20And deadly animals.
0:00:21 > 0:00:24And you're coming with me, every step of the way!
0:00:26 > 0:00:27Arghhhh!
0:00:30 > 0:00:31This time on Pole To Pole -
0:00:31 > 0:00:33we're on a mission to explore
0:00:33 > 0:00:36our planet's lethal forces of nature.
0:00:36 > 0:00:38Oh, wow!
0:00:38 > 0:00:40The elemental furies of fire,
0:00:40 > 0:00:42ice, water
0:00:42 > 0:00:44and wind.
0:00:44 > 0:00:46These are the most dangerous things we've ever featured
0:00:46 > 0:00:48on Deadly.
0:00:48 > 0:00:52With the power to change the face of the earth for ever.
0:00:55 > 0:00:57I'll be venturing
0:00:57 > 0:01:00into freezing depths where no-one's been before.
0:01:00 > 0:01:02If I tried to head down there,
0:01:02 > 0:01:05I think it'd just be too dangerous. I wouldn't make it.
0:01:05 > 0:01:08Then encountering some epic winds that truly blow me away.
0:01:13 > 0:01:16Argh! This is absolutely nuts.
0:01:16 > 0:01:19But first, we're off to experience
0:01:19 > 0:01:22a fiery force that can scorch everything in its path.
0:01:27 > 0:01:30Every year, Australia has around 50,000 wildfires
0:01:30 > 0:01:33that can rage through millions of acres of land.
0:01:33 > 0:01:34Unbelievable!
0:01:37 > 0:01:38Wow, look at this going up.
0:01:41 > 0:01:43Look at that!
0:01:43 > 0:01:45That is full-on.
0:01:48 > 0:01:52One of the most lethal forces in nature is fire.
0:01:52 > 0:01:55Here in the Northern Territories where the ground is so dry
0:01:55 > 0:02:00and all the trees are so dry, a wildfire can sweep through an area
0:02:00 > 0:02:02and kill just about everything in its path.
0:02:04 > 0:02:07Fire is one of the most destructive forces on earth.
0:02:07 > 0:02:10Burning huge tracts of land and lasting for months
0:02:10 > 0:02:13at a time, wildfires can be truly catastrophic.
0:02:17 > 0:02:20They ravage landscapes and rip right through forests.
0:02:20 > 0:02:22Wiping out most life in their path.
0:02:26 > 0:02:29But there is a far more formidable fiery force,
0:02:29 > 0:02:31one that's hot enough to melt rock itself,
0:02:34 > 0:02:35the volcano.
0:02:37 > 0:02:40Volcanoes are violent forces where molten rock explodes
0:02:40 > 0:02:41from the depths of the earth,
0:02:41 > 0:02:43scalding,
0:02:43 > 0:02:44scorching,
0:02:44 > 0:02:46burning and vaporising.
0:02:48 > 0:02:51The best place to get close to one of these violent volcanoes
0:02:51 > 0:02:53is Hawaii,
0:02:53 > 0:02:56home to one of the largest volcanoes on earth.
0:02:58 > 0:03:01And we're here to witness the spectacular sight
0:03:01 > 0:03:04where hot lava meets the ocean.
0:03:04 > 0:03:06Ah! Oh, wow!
0:03:09 > 0:03:11That is unreal.
0:03:12 > 0:03:14Wow, wow!
0:03:17 > 0:03:20There are very few places on the planet where you can see
0:03:20 > 0:03:22something like this.
0:03:22 > 0:03:26Lava pouring... molten rock directly into the sea.
0:03:26 > 0:03:31I mean, can you imagine how hot it has to be to melt rock?
0:03:31 > 0:03:34To turn rock into liquid, so it's like treacle.
0:03:35 > 0:03:37As soon as this melted rock hits the ocean,
0:03:37 > 0:03:42the water instantly boils and sends up plumes of superheated steam.
0:03:45 > 0:03:48I've been working with deadly animals for most of my life,
0:03:48 > 0:03:50and they don't really frighten me,
0:03:50 > 0:03:53but there's something about this that really puts the hackles up
0:03:53 > 0:03:55on the back of my neck.
0:03:55 > 0:03:57It is a true inferno.
0:03:57 > 0:04:00It's one of the most exciting, but possibly the most chilling
0:04:00 > 0:04:03and overpowering things I think I've ever seen.
0:04:08 > 0:04:11Having seen this sea-based spectacle,
0:04:11 > 0:04:14I now want to get to the source of this lava, where it first emerges
0:04:14 > 0:04:16from the earth.
0:04:19 > 0:04:22Several miles inland is the erupting volcanic caldera,
0:04:22 > 0:04:25but the only way to approach is by air.
0:04:32 > 0:04:35As we make our way to the caldera,
0:04:35 > 0:04:38the lava's destructive force is overwhelming.
0:04:38 > 0:04:41The blackness, the devastation just goes on
0:04:41 > 0:04:44for miles, as far as the eye can see.
0:04:44 > 0:04:48But here beneath me, everything's been destroyed
0:04:48 > 0:04:50by this unstoppable river of lava.
0:04:53 > 0:04:56But it's not just the lava that makes volcanoes lethal.
0:04:56 > 0:05:00Eruptions are often accompanied by clouds of mega hot toxic gas
0:05:00 > 0:05:03and burning dust, which strips the land.
0:05:08 > 0:05:12At the source we can see where all this force is unleashed.
0:05:12 > 0:05:14Ooh!
0:05:14 > 0:05:18You can see where all of the molten rock is coming to the surface.
0:05:20 > 0:05:21Can you get a shot of that, Luke?
0:05:24 > 0:05:28You see the perfect round crater, and I can feel the heat - even with
0:05:28 > 0:05:30the rotors above us blowing it away,
0:05:30 > 0:05:33it's still coming up like a furnace towards us.
0:05:36 > 0:05:41It's a magnificent sight but really, actually quite frightening.
0:05:41 > 0:05:45OK, the next thing we want to do is to land on some of this black
0:05:45 > 0:05:49pavement. I want to really feel it beneath my toes.
0:05:52 > 0:05:55Our plan is to find an area of liquid lava to measure
0:05:55 > 0:05:57how hot it really is.
0:06:04 > 0:06:07It's kind of a strange sensation,
0:06:07 > 0:06:10walking along with the rock underneath your foot crackling
0:06:10 > 0:06:13and popping - it's almost like walking on Rice Krispies.
0:06:15 > 0:06:18'Below my feet is cooled lava, which has created new rock.
0:06:20 > 0:06:23'Hard, dark, moulded like cast iron.
0:06:23 > 0:06:26'But what we really want is some fresh, still liquid lava.'
0:06:26 > 0:06:30All of a sudden, I've just been hit by a wall of heat...
0:06:34 > 0:06:39and there is our first explosion of lava.
0:06:39 > 0:06:41Look at that.
0:06:41 > 0:06:45Flooding out. So this is a unique opportunity to actually measure
0:06:45 > 0:06:47how hot this rock really is.
0:06:47 > 0:06:51I've got here what is essentially a very, very expensive,
0:06:51 > 0:06:53very, very tough thermometer.
0:06:53 > 0:06:57So I'll go in, whack a hole in this hot lava here and just
0:06:57 > 0:07:00place the thermometer inside, and Simon the sound recordist here
0:07:00 > 0:07:02is going to be standing back at a safe distance
0:07:02 > 0:07:04to record how hot it is.
0:07:04 > 0:07:07The only safety equipment I've really got is a pair
0:07:07 > 0:07:11of oven gloves, and I have to be honest - at the moment,
0:07:11 > 0:07:13it really doesn't feel like enough.
0:07:29 > 0:07:30Oh!
0:07:31 > 0:07:35Ha! OK. Right, that's really, really hot.
0:07:37 > 0:07:38Right, come on, Backshall.
0:07:42 > 0:07:45Argh!
0:07:47 > 0:07:48Argh!
0:07:50 > 0:07:52You got a reading?
0:07:53 > 0:07:55- 29.- Whoa. 106.
0:07:57 > 0:07:58Argh!
0:07:59 > 0:08:00Did you see how hot that went?
0:08:00 > 0:08:04Yeah, just... I mean, it's like 29 and it jumped up to over 1,000.
0:08:05 > 0:08:10'Reaching a temperature of 1,136 degrees.
0:08:10 > 0:08:13'That's hot enough to melt gold.
0:08:13 > 0:08:15'You can imagine the potential.'
0:08:22 > 0:08:26But having felt the heat of Hawaii's volcanoes,
0:08:26 > 0:08:29I want to go one step further and show you a place where volcanoes
0:08:29 > 0:08:31turn supersized.
0:08:34 > 0:08:38Yellowstone, in the northwest United States.
0:08:38 > 0:08:43Yellowstone sits in the 50-mile-wide crater of a super volcano.
0:08:43 > 0:08:47When this volcano erupts, it could be the largest natural disaster
0:08:47 > 0:08:49in the history of humankind
0:08:49 > 0:08:52and change the face of the planet for ever.
0:09:00 > 0:09:02Its eruption will have a force
0:09:02 > 0:09:05thousands of times greater than a normal volcano.
0:09:13 > 0:09:15It would blast away entire mountains
0:09:15 > 0:09:17and throw hundreds of tonnes of debris
0:09:17 > 0:09:19into the atmosphere.
0:09:29 > 0:09:31Once this settles,
0:09:31 > 0:09:35most of the USA would be covered in a blanket of ash and rock.
0:09:35 > 0:09:38Dust and gas clouds would block out the sun for months,
0:09:38 > 0:09:42causing global temperatures to plummet, affecting life
0:09:42 > 0:09:44all over the planet.
0:09:45 > 0:09:48It tends to erupt about every 600,000 years.
0:09:48 > 0:09:52The last time it erupted was about 640,000 years ago,
0:09:52 > 0:09:54so we're well overdue.
0:09:54 > 0:09:56A super volcano that could completely change
0:09:56 > 0:10:00the course of life as we know it - that is definitely Deadly.
0:10:00 > 0:10:05Reaching temperatures of over 1,000 degrees centigrade.
0:10:05 > 0:10:10With clouds of gas and rivers of lava that tear across the landscape.
0:10:10 > 0:10:13And the ability to change the face of the planet for ever.
0:10:14 > 0:10:17The planet's volcanoes are formidable fiery forces.
0:10:17 > 0:10:20Deadly.
0:10:21 > 0:10:25From these superheated explosive forces to subzero temperatures
0:10:25 > 0:10:27and the power of ice.
0:10:28 > 0:10:32When it starts to move, ice can become a force to be reckoned with.
0:10:35 > 0:10:37Avalanches pummel the landscape,
0:10:37 > 0:10:39bringing down thousands of tonnes of snow,
0:10:39 > 0:10:42enveloping everything in their path.
0:10:44 > 0:10:48Avalanches can decimate entire mountainsides,
0:10:48 > 0:10:50but they're over in minutes.
0:10:50 > 0:10:53There's one frozen force though that grinds away
0:10:53 > 0:10:58over thousands of years and has the power to sculpt entire landscapes.
0:10:58 > 0:10:59The glacier.
0:11:01 > 0:11:05Glaciers are massive rivers of compacted ice.
0:11:05 > 0:11:09They're constantly moving, carving valleys and ploughing through
0:11:09 > 0:11:11everything in their path.
0:11:17 > 0:11:19Glaciers are such a mighty force
0:11:19 > 0:11:21of nature that their impact is felt globally.
0:11:21 > 0:11:25Calved icebergs help regulate global water temperatures
0:11:25 > 0:11:28and shape landscapes across the planet.
0:11:30 > 0:11:33And I'm hitting Alaska to go deep inside
0:11:33 > 0:11:35a glacier to explore the heart
0:11:35 > 0:11:37of this freezing force of nature.
0:11:44 > 0:11:47All of the ice on the surface of the glacier is constantly heated
0:11:47 > 0:11:50by the sun and forms little streams like this,
0:11:50 > 0:11:54which eventually run into big rivers.
0:11:54 > 0:11:57Now, these rivers create an enormous amount of water,
0:11:57 > 0:12:00and that water has to go somewhere.
0:12:00 > 0:12:03Eventually, it finds a weak point in the glacier
0:12:03 > 0:12:06and it burrows down into a whirlpool
0:12:06 > 0:12:08called a moulin.
0:12:08 > 0:12:10This is the gateway
0:12:10 > 0:12:12to the guts of the glacier.
0:12:12 > 0:12:15It's an incredibly frightening place,
0:12:15 > 0:12:17and believe it or not, that's where we're going.
0:12:17 > 0:12:20The team and I get to work
0:12:20 > 0:12:24setting up a rope system to climb down into the moulin.
0:12:28 > 0:12:31Whilst they are very dangerous places,
0:12:31 > 0:12:34moulins are incredibly exciting,
0:12:34 > 0:12:35and you can say with confidence
0:12:35 > 0:12:38that no-one has ever been down this before,
0:12:38 > 0:12:40because the place itself is always changing.
0:12:40 > 0:12:42It's never been like it is right now,
0:12:42 > 0:12:44and that, to me,
0:12:44 > 0:12:47is the most exciting thing about this environment.
0:12:51 > 0:12:55Moulins are formed when a waterfall cuts its way into the glacier.
0:12:57 > 0:13:00The ice has been compacted for hundreds of years.
0:13:02 > 0:13:05In the heart of the moulin, temperatures drop
0:13:05 > 0:13:08well below freezing, and the caves shimmer a beautiful deep blue.
0:13:10 > 0:13:12But this beauty belies the danger of a moulin.
0:13:14 > 0:13:19Glaciers are constantly moving. I could get squashed like a gnat.
0:13:24 > 0:13:27'Kitted up and with all the ropes in place,
0:13:27 > 0:13:30'it's time for me to descend into the abyss.'
0:13:30 > 0:13:34OK, I'm all prepared for my trip into the underworld.
0:13:34 > 0:13:37I've got my waterproof suit on. I've also got this camera,
0:13:37 > 0:13:40which we usually use for filming underwater,
0:13:40 > 0:13:42and as soon as I get over the edge
0:13:42 > 0:13:43and I'm into the waterfall,
0:13:43 > 0:13:45I'll lose contact with the rest of the crew.
0:13:45 > 0:13:47This will be seriously cold.
0:13:47 > 0:13:51That is the understatement of the century.
0:13:53 > 0:13:55The glacial meltwater thunders into the blue depths,
0:13:55 > 0:14:00and in a few minutes, it's going to be crashing over me.
0:14:02 > 0:14:05I'll get absolutely hammered here.
0:14:10 > 0:14:11Whoa.
0:14:11 > 0:14:13This looks absolutely brutal.
0:14:13 > 0:14:17I've got two separate falls coming in. The big one over there,
0:14:17 > 0:14:21I'll be able to stay clear of for most of the way.
0:14:21 > 0:14:26That one'll hit me within a few metres,
0:14:26 > 0:14:29and the water will numb my brain and my fingers,
0:14:29 > 0:14:32and my whole body will start to shut down really quickly.
0:14:56 > 0:15:00This would have to be one of the most hostile places
0:15:00 > 0:15:02you can ever be in.
0:15:02 > 0:15:04This is a place that human beings
0:15:04 > 0:15:07are simply not supposed to be.
0:15:10 > 0:15:13I'm looking down to the very bottom of a glacier, an enormous,
0:15:13 > 0:15:21moving river of ice. If I didn't have my drysuit,
0:15:21 > 0:15:25I wouldn't last seconds here.
0:15:25 > 0:15:28The water is only just above freezing
0:15:28 > 0:15:31and thundering down around my ears.
0:15:32 > 0:15:35'Some moulins descend hundreds of metres,
0:15:35 > 0:15:37'right to the base of the glacier.
0:15:39 > 0:15:42'To be inside this giant force of nature is a real
0:15:42 > 0:15:44'assault on the senses.
0:15:45 > 0:15:49'After 30 minutes down here with icy water chilling me to the bone,
0:15:49 > 0:15:51'my whole body is going numb.
0:15:51 > 0:15:55'It's fascinating to be here, but it's just too much.'
0:15:55 > 0:15:58It's such an incredibly beautiful place,
0:15:58 > 0:16:01but it's almost too frightening
0:16:01 > 0:16:04and too overwhelming to appreciate.
0:16:07 > 0:16:10I don't think I should go on any further.
0:16:10 > 0:16:13I think it'd just be too dangerous,
0:16:13 > 0:16:18and look at all that water thundering down below me.
0:16:18 > 0:16:22I think, if I tried to head down there,
0:16:22 > 0:16:24I wouldn't make it.
0:16:29 > 0:16:32OK, I need to start climbing back up now.
0:16:36 > 0:16:38One last ledge.
0:16:52 > 0:16:53Ah!
0:16:56 > 0:16:59Argh! Come on.
0:17:13 > 0:17:18That was probably the most hardcore thing I've ever done on Deadly.
0:17:18 > 0:17:22It'll be hours before I can feel my fingers again.
0:17:24 > 0:17:28I am totally smashed...
0:17:30 > 0:17:32But...there's no doubt that
0:17:33 > 0:17:39places like moulins are a lethal environment,
0:17:39 > 0:17:42definitely Deadly.
0:17:43 > 0:17:47Crevasses and moulins are gateways to the abyss.
0:17:47 > 0:17:50A glacier is an unstoppable force that can shift
0:17:50 > 0:17:52and collapse without warning.
0:17:52 > 0:17:55They carve mountainsides and everything in their path.
0:17:57 > 0:18:00Glaciers are a phenomenally destructive rivers of ice.
0:18:00 > 0:18:01'Deadly!'
0:18:04 > 0:18:08From ice giants to the power of water...
0:18:08 > 0:18:11Our next force of nature is the ocean.
0:18:12 > 0:18:16And to see why, we're heading back to Hawaii.
0:18:16 > 0:18:19Here in Hawaii, where the waves have had
0:18:19 > 0:18:21thousands of miles of open ocean to build up some steam,
0:18:21 > 0:18:24they can become a truly deadly force of nature.
0:18:29 > 0:18:33The attrition and force of big waves can be catastrophic to coastlines...
0:18:34 > 0:18:36..smashing cliffs...
0:18:38 > 0:18:39..undercutting rocks....
0:18:40 > 0:18:42..and pounding into sand.
0:18:43 > 0:18:48These mighty breakers can create epic amounts of erosion.
0:18:57 > 0:19:01The biggest waves are often caused by violent weather systems
0:19:01 > 0:19:05which form over the oceans across the Tropics.
0:19:09 > 0:19:12Super-storms can become hurricanes and typhoons,
0:19:12 > 0:19:15stretching over 1,000 miles wide,
0:19:15 > 0:19:19they could easily engulf the whole of the United Kingdom.
0:19:20 > 0:19:23When these raging seas collide with land,
0:19:23 > 0:19:26they can cause storm surges that wreak havoc.
0:19:28 > 0:19:31The largest storm surges can rage up to ten miles inland,
0:19:31 > 0:19:35bringing flooding and devastation that can take years to recover from.
0:19:39 > 0:19:42These giant waves inundate miles of coastline...
0:19:45 > 0:19:47..causing massive amounts of erosion...
0:19:48 > 0:19:51..flooding homes....
0:19:53 > 0:19:57..and wiping out vegetation for miles.
0:19:57 > 0:20:01These storm-surge waves are watery destroyers.
0:20:06 > 0:20:09As well as creating devastating waves,
0:20:09 > 0:20:13hurricanes also bring storm-force winds.
0:20:14 > 0:20:18These winds are the final force of nature I want to experience,
0:20:18 > 0:20:21by creating my own tornado-strength winds.
0:20:23 > 0:20:25While hurricanes form over the ocean,
0:20:25 > 0:20:28tornados are normally created over land
0:20:28 > 0:20:32and have winds that tear through everything in their path.
0:20:32 > 0:20:36Ripping up trees, hurling vehicles hundreds of metres into the air
0:20:36 > 0:20:38and reducing houses to splinters,
0:20:38 > 0:20:40nothing can rival their earth-shattering power.
0:20:46 > 0:20:48The aftermath of storm-force winds
0:20:48 > 0:20:51can leave communities devastated for years.
0:20:56 > 0:20:59To experience the real destructive force of these winds,
0:20:59 > 0:21:02we're heading to Texas, in Tornado Alley.
0:21:03 > 0:21:06The hot spot of these catastrophic twisters.
0:21:11 > 0:21:14Well, this really puts it into perspective.
0:21:14 > 0:21:17It's torn apart this house,
0:21:17 > 0:21:19almost like it was a doll's house,
0:21:19 > 0:21:21and tossed cars around
0:21:21 > 0:21:24and caused absolute devastation.
0:21:24 > 0:21:26This here is a testament
0:21:26 > 0:21:29to what a deadly force of nature tornadoes can be.
0:21:29 > 0:21:32It's too dangerous
0:21:32 > 0:21:34to experience a real tornado like this first-hand, so...
0:21:34 > 0:21:39Instead of doing that, we decided to create our own, using this...
0:21:42 > 0:21:44This is an Albatros fighter jet,
0:21:44 > 0:21:46and it's a seriously mean machine.
0:21:49 > 0:21:52Powered by an immense jet engine,
0:21:52 > 0:21:55it can fly at over 450mph.
0:21:58 > 0:22:01But we don't need to leave the ground to feel its force.
0:22:03 > 0:22:06The bit we're interested in is this - the exhaust.
0:22:06 > 0:22:07When this jet fires up,
0:22:07 > 0:22:09wind is going to come out of the back of here
0:22:09 > 0:22:12of well over 100mph, possibly considerably more,
0:22:12 > 0:22:14and I'm going to try and walk up the back
0:22:14 > 0:22:18and experience how it feels to be in a tornado.
0:22:20 > 0:22:22I'm no stranger to danger on Deadly.
0:22:25 > 0:22:30But staring down the barrel of a jet engine is a real step up.
0:22:30 > 0:22:32All right, Dan, fire her up.
0:22:33 > 0:22:35Here goes nothing.
0:22:38 > 0:22:40Coming up.
0:22:45 > 0:22:48'The engines are on low thrust,
0:22:48 > 0:22:52'roughly equivalent to a force 1 tornado, the least severe.
0:22:52 > 0:22:55'With winds speeds reaching over 80mph,
0:22:55 > 0:22:58'it's already almost impossible to stand up.'
0:22:58 > 0:23:00- (SHOUTING): - When you're in winds like this,
0:23:00 > 0:23:01the first thing that happens
0:23:01 > 0:23:05is that you start to get rain and water.
0:23:06 > 0:23:08Argh!
0:23:08 > 0:23:11'At this speed, the water slams into me, stinging my face.
0:23:11 > 0:23:13'Just imagine what it would be like
0:23:13 > 0:23:15'being hit by hail and ice in an actual twister.'
0:23:20 > 0:23:23Argh! There goes my... Ear-defenders have gone.
0:23:23 > 0:23:26It's all right, it'll be OK.
0:23:26 > 0:23:29'Next up, this bag of flour is going to simulate dust
0:23:29 > 0:23:30'sucking into our tornado.'
0:23:32 > 0:23:35Argh. Ah, this is absolutely nuts!
0:23:35 > 0:23:39'In a real tornado, dust and earth travelling over 300mph
0:23:39 > 0:23:42'can strip the bark off trees and blast the paint off cars.'
0:23:51 > 0:23:53'The pilot is increasing the thrust.'
0:23:53 > 0:23:56Do you want more power? I still got more.
0:23:56 > 0:23:59Come on, send them at me, I can take it!
0:23:59 > 0:24:03'With wind speeds over 150mph,
0:24:03 > 0:24:05'I'm now in a category 3 tornado.'
0:24:10 > 0:24:12'Tornadoes go up to a level 5,
0:24:12 > 0:24:15'but I've been floored by a 3.'
0:24:15 > 0:24:17Oh, my goodness.
0:24:18 > 0:24:24I've just been pretty much blown into the next county.
0:24:26 > 0:24:28That was incredible!
0:24:30 > 0:24:32It was a horrifying sensation
0:24:32 > 0:24:36of what it must feel like to be inside the eye of a tornado.
0:24:36 > 0:24:39Erm, I don't really know quite what to say.
0:24:39 > 0:24:42It's completely taken my senses away.
0:24:42 > 0:24:47But although this has been rather dramatic, rather exciting,
0:24:47 > 0:24:51obviously there's a very, very serious side
0:24:51 > 0:24:55to what a force of nature like a tornado can do in real life.
0:24:56 > 0:25:00There are far more dangerous objects than dust and water
0:25:00 > 0:25:02that get pulled into a tornado.
0:25:05 > 0:25:08These twisters mash up and spew out everything in their path.
0:25:11 > 0:25:14Like natural wrecking balls filled with lethal projectiles,
0:25:14 > 0:25:16they blaze a trail of devastation.
0:25:18 > 0:25:21It's too dangerous to put me in the line of fire,
0:25:21 > 0:25:23so we're towing in a car to use as a target.
0:25:26 > 0:25:30Winds produced by our jet aren't strong enough to blow the car away,
0:25:30 > 0:25:32but we can show you what everyday objects will do
0:25:32 > 0:25:34when caught in these winds.
0:25:34 > 0:25:36- ENGINE WHOOSHES (SHOUTING)- Right, the power
0:25:36 > 0:25:37is starting to build.
0:25:43 > 0:25:46'Fence posts and timbers ripped off roofs
0:25:46 > 0:25:47'turn into jagged javelins.'
0:25:53 > 0:25:56'And garden ornaments become potential destroyers.'
0:26:04 > 0:26:07'The flowerpot explodes on impact,
0:26:07 > 0:26:10'showering serrated pieces in every direction.
0:26:10 > 0:26:12'Each one becomes its own piece of shrapnel.'
0:26:20 > 0:26:25OK, let's see what utter devastation we've wrought on our car.
0:26:26 > 0:26:30Now, this is actually pretty frightening.
0:26:30 > 0:26:33That massive dent there
0:26:33 > 0:26:36from the base of a humble flowerpot.
0:26:36 > 0:26:39Just imagine what would be caused by something heavier.
0:26:39 > 0:26:40You have to say, looking at this,
0:26:40 > 0:26:43that there is no doubt that tornadoes,
0:26:43 > 0:26:45this remarkable force of nature,
0:26:45 > 0:26:49have the power to make us feel incredibly fragile and vulnerable,
0:26:49 > 0:26:52and, for that reason, they are without doubt, deadly.
0:26:54 > 0:26:57With winds that can reach around 300mph...
0:26:59 > 0:27:01..tearing through landscapes...
0:27:03 > 0:27:06..and wrecking lives...
0:27:07 > 0:27:11..tornadoes have little competition when it comes to destruction.
0:27:13 > 0:27:16This journey through the mighty elements
0:27:16 > 0:27:18of ice, wind, water and fire
0:27:18 > 0:27:21has shown us just how deadly
0:27:21 > 0:27:23the planet's forces of nature can become.
0:27:27 > 0:27:29They've shaped our planet,
0:27:29 > 0:27:31and their destructive power reminds us
0:27:31 > 0:27:34of how vulnerable we humans can be.
0:27:43 > 0:27:46Ah, this is absolutely nuts!
0:27:46 > 0:27:48'Join me next time on Deadly Pole To Pole.'