0:00:02 > 0:00:05# Let him blow, let him blow
0:00:05 > 0:00:08# From the east to the west.
0:00:08 > 0:00:09# I love you the best. #
0:00:09 > 0:00:11Wind.
0:00:11 > 0:00:13The British get a lot of it.
0:00:13 > 0:00:19Our language is full of wind and the words that we use to describe it are kind of windy words.
0:00:19 > 0:00:24Windbag, whistle down the wind, wind of change, it's an ill wind.
0:00:24 > 0:00:26We can't see the wind.
0:00:26 > 0:00:30But we can feel it...
0:00:30 > 0:00:32and see its effects.
0:00:32 > 0:00:38I was frightened stiff because it was something I couldn't control.
0:00:38 > 0:00:42So how did we discover what causes the winds?
0:00:42 > 0:00:46Where they come from? Why they change?
0:00:46 > 0:00:50How to forecast them, how to harness them.
0:00:50 > 0:00:53Scientists are learning to predict the slightest breeze,
0:00:53 > 0:00:56and the fastest tornado.
0:00:56 > 0:00:59Although we understand the wind,
0:00:59 > 0:01:01will we ever control it?
0:01:01 > 0:01:03# From the east to the west
0:01:03 > 0:01:05# I love you the best. #
0:01:14 > 0:01:16Air is invisible...
0:01:16 > 0:01:20until it moves, then we call it wind.
0:01:22 > 0:01:25Once, we believed the wind was a punishment from the gods.
0:01:26 > 0:01:29Then science explained the wind.
0:01:29 > 0:01:33It took over 1,000 years to put the pieces together.
0:01:33 > 0:01:35But now we know.
0:01:37 > 0:01:41It is the interaction of temperature, pressure and the Earth's rotation.
0:01:41 > 0:01:45It's a complex cocktail.
0:01:47 > 0:01:49Wind is moving air,
0:01:49 > 0:01:52so we are standing on the Earth's surface
0:01:52 > 0:01:56and if the air moves past us, then we call that wind.
0:01:58 > 0:02:02The atmosphere moves far more in some places than in others.
0:02:02 > 0:02:06We British get a lot of movement, a lot of wind.
0:02:06 > 0:02:07Why is that?
0:02:07 > 0:02:09We're right on the eastern seaboard
0:02:09 > 0:02:15of a major ocean and this puts us right at the end of the storm tracks.
0:02:15 > 0:02:22The storms form in the western part of the Atlantic generally,
0:02:22 > 0:02:25and they come across and then, of course, we get hit by them.
0:02:33 > 0:02:36And the first port of call for the Atlantic winds
0:02:36 > 0:02:41is an island in the Hebrides, off the west coast of Scotland.
0:02:41 > 0:02:45This is Tiree, the windiest place in the British Isles.
0:02:45 > 0:02:49Maybe not today, but don't be fooled.
0:02:49 > 0:02:51You step out of the front door
0:02:51 > 0:02:53and if you're not leaning forwards at 45 degrees
0:02:53 > 0:02:55you're going to be blown over.
0:02:55 > 0:02:58It's a different experience altogether and most people coming up here
0:02:58 > 0:03:01who haven't experienced that kind of wind before are very welcome to come up here in December, January
0:03:01 > 0:03:06and February, and you won't know what you're in for until you do actually experience it.
0:03:11 > 0:03:17Tiree is an island formed from windborne sand. There are few trees here.
0:03:17 > 0:03:23It's so flat and low there's nothing to stop the winds as they rush onto mainland Britain.
0:03:26 > 0:03:29And once the wind arrives, we never know quite what to expect.
0:03:33 > 0:03:36It can be playful, exhilarating,
0:03:36 > 0:03:40buffeting, and threatening.
0:03:40 > 0:03:42What begins as a whisper
0:03:42 > 0:03:47can become a shout, and the shout a scream.
0:04:02 > 0:04:05The wind blows good fortune as well as bad.
0:04:05 > 0:04:10On February the 5th 1941, off the Isle of Eriskay in the Hebrides,
0:04:10 > 0:04:14a ship called the SS Politician was blown onto the rocks.
0:04:18 > 0:04:23Aboard her were 22,000 cases of finest scotch whisky.
0:04:23 > 0:04:28There was a war on and you couldn't get whisky for love nor money.
0:04:30 > 0:04:36But the west wind delivered 264,000 bottles to the islanders.
0:04:36 > 0:04:41They liberated 84,000 before custom officials blew the wreck sky high.
0:04:41 > 0:04:44It's an ill wind, they say.
0:04:45 > 0:04:50But how can the wind disperse a fleet or deliver crates of whisky?
0:04:50 > 0:04:54The first clue comes to us from the seafaring Greeks.
0:04:56 > 0:05:00Aristotle proposed that the winds were "exhalations"
0:05:00 > 0:05:03caused by the sun's effect on the Earth.
0:05:06 > 0:05:09During the day, where the sun hit dry land,
0:05:09 > 0:05:14Aristotle said there would be warm, dry exhalations.
0:05:14 > 0:05:20Where the sun hit water, or snow, cool, moist exhalations.
0:05:20 > 0:05:27According to Aristotle, each evening these large blocks of warm and cool air would mingle
0:05:27 > 0:05:32as in a gentle breeze, or wrestle and clash like two warring gods.
0:05:34 > 0:05:40Today, scientists recognise the meeting of warm and cold air as a front.
0:05:40 > 0:05:46The way that the atmosphere organises this is it brings warm and cold air to close proximity,
0:05:46 > 0:05:48and this is what we call a front.
0:05:48 > 0:05:53So you have a front forming where there is a very sharp gradient in temperature.
0:05:57 > 0:06:01In the laboratory, it's possible to simulate a simple
0:06:01 > 0:06:06cold front just by adding salt and dye to water at one end of a tank.
0:06:07 > 0:06:12Cold air, represented by the blue water, is denser and heavier than warm air.
0:06:14 > 0:06:19When a cold front pushes forward, the warmer air rises over it.
0:06:19 > 0:06:26The movement of warm and cold air at the fronts gives us much of the wind we experience.
0:06:26 > 0:06:31The greater the temperature difference at a front, the stronger the wind.
0:06:31 > 0:06:33And Aristotle was right.
0:06:33 > 0:06:37It is the sun that drives the circulation of these air masses.
0:06:37 > 0:06:40The cause of the wind is actually the sun in the first place.
0:06:40 > 0:06:42That's what starts it all off.
0:06:42 > 0:06:48The sun comes and it stirs it all up and it creates temperature contrasts and we get wind.
0:06:48 > 0:06:53Britain is an exciting place to live, in terms of the weather.
0:06:53 > 0:06:59Perhaps if you were in a more continental location, you'd tend to get hot summers
0:06:59 > 0:07:06and cold winters, but you wouldn't get the variety of fronts that we see from day to day in our weather.
0:07:10 > 0:07:15# Stormy weather
0:07:15 > 0:07:21# since Monday night... #
0:07:21 > 0:07:24Exciting, perhaps.
0:07:24 > 0:07:30But some of us tend to take these fronts and winds rather personally.
0:07:35 > 0:07:39Paul Rose is an explorer and sailor.
0:07:39 > 0:07:42He knows what it's like to be on the receiving end of the wind.
0:07:42 > 0:07:44I've been in situations in my life
0:07:44 > 0:07:49when I'm pretty certain that wind's out to get me and has a personality!
0:07:49 > 0:07:54No matter how much rational and science thinking you might have,
0:07:54 > 0:07:56that the wind is completely impersonal...
0:07:56 > 0:08:01Forget it, because when you're really up against it, you're pretty sure it's out to get you.
0:08:02 > 0:08:05Some believe the wind is heaven-sent.
0:08:05 > 0:08:07Others are sure it comes from elsewhere.
0:08:07 > 0:08:12My mother's favourite phrase was, even if it was only slightly breezy,
0:08:12 > 0:08:15she'd say, "This wind is straight from Siberia."
0:08:15 > 0:08:20And that's interesting, the idea that somehow the wind has come from somewhere else to torment us.
0:08:22 > 0:08:25The Greeks blamed the gods for their torment.
0:08:26 > 0:08:28Zephyrus was the friendly god.
0:08:28 > 0:08:31He was the one who had the pleasant breezes.
0:08:31 > 0:08:35He's wearing light clothing, smiling, bringing in bowls of fruit.
0:08:37 > 0:08:44You have Kaikias, he's got a great big sort of shield and it's full of hailstones.
0:08:44 > 0:08:48That's the vicious north-easter that sweeps down.
0:08:49 > 0:08:52The Greeks were fascinated by the winds.
0:08:52 > 0:08:54They're called arrogant,
0:08:56 > 0:08:58wild,
0:08:58 > 0:09:02uncontrollable, vicious.
0:09:02 > 0:09:07And for this, the gods got so sick of them that they had them put
0:09:07 > 0:09:13under a king, Aeolus, and walled up in a cavern under a mountain.
0:09:13 > 0:09:17There they all are, like an army sort of forming ranks, and when
0:09:17 > 0:09:21the doors open in the mountainside, out they go and hell breaks loose.
0:09:31 > 0:09:37It wasn't the gods that broke loose on the night of January 15th, 1968.
0:09:37 > 0:09:41What began with a cold front in the Caribbean
0:09:41 > 0:09:45ended with an almighty storm across northern Scotland.
0:09:45 > 0:09:50Wind gusts of 117mph were recorded on Tiree.
0:09:50 > 0:09:54On the Ayrshire coast, it woke a young girl.
0:09:54 > 0:10:01I could hear just this huge rushing noise outside of my bedroom window,
0:10:01 > 0:10:06and it sounded just like a steam train whooshing past.
0:10:08 > 0:10:11And then the storm force wind howled up the River Clyde.
0:10:11 > 0:10:15There it met the high tenements of Glasgow.
0:10:17 > 0:10:22Willy Mackie was just 21 years old, and living with his parents.
0:10:22 > 0:10:27Back in 1968, I stayed at 555 Dumbarton Rd,
0:10:27 > 0:10:29which was actually here.
0:10:34 > 0:10:37About three in the morning, there was a bang at the door
0:10:37 > 0:10:40and it was the neighbour across the landing.
0:10:40 > 0:10:44He shouted, "You'll need to get out quick because the building's falling down."
0:10:44 > 0:10:48All the people that stayed in the building ran into the middle of Dumbarton Rd.
0:10:48 > 0:10:53So we assembled there and did a head-count and found there was four people missing.
0:10:57 > 0:11:02That's what left of the chimney, which was about 15ft tall.
0:11:02 > 0:11:05And the wind blew the whole of that chimney over onto our roof
0:11:05 > 0:11:10and then from there, that chimney went straight through all the front bedrooms, right into the basement.
0:11:15 > 0:11:17But the wind didn't stop in Glasgow.
0:11:17 > 0:11:21It carried on, reaching the outskirts of Edinburgh.
0:11:21 > 0:11:24To come back after all these years...
0:11:24 > 0:11:27I found that difficult.
0:11:27 > 0:11:32That's very difficult, seeing the name. That's very difficult.
0:11:32 > 0:11:36Elsie Greenan, was also 21 in 1968.
0:11:36 > 0:11:41She'd recently married and was living with her parents in Northcote Place, Edinburgh.
0:11:42 > 0:11:44Her tenement building is now demolished.
0:11:44 > 0:11:48It's the first time she's returned to the area for many years.
0:11:48 > 0:11:55Roughly six o'clock in the morning, there was a huge, huge whooshing noise.
0:11:55 > 0:11:57It was just horrendous.
0:11:57 > 0:11:59Just this terrible, terrible noise.
0:11:59 > 0:12:04And I got up and switched the light on, and what had happened was the chimney in the kitchen
0:12:04 > 0:12:11had been blown over and the soot had come down the chimney in the kitchen and was all over the carpet.
0:12:11 > 0:12:16So my first thought was, "Oh, my God, Mum's new carpet."
0:12:16 > 0:12:18I went through to tell her.
0:12:18 > 0:12:21And when I opened the bedroom door,
0:12:21 > 0:12:24there was just nothing there,
0:12:24 > 0:12:28except this huge... huge pile of rubble.
0:12:28 > 0:12:33No ceiling. And the wind was unbelievable. It was awful.
0:12:33 > 0:12:36You don't think, when you're looking in on it, they're dead.
0:12:36 > 0:12:40You think they're under there and they're OK.
0:12:41 > 0:12:44But Elsie's parents were dead.
0:12:45 > 0:12:47Willy Mackie's neighbours were killed.
0:12:55 > 0:13:00In all, 20 people died, and the scars remain.
0:13:00 > 0:13:08To this day, if it's an exceptionally high wind, I mean a real high wind, I'm still nervous.
0:13:11 > 0:13:17I can, believe it or not, still taste the dust from that night.
0:13:17 > 0:13:20I can still smell it. I can still taste it.
0:13:20 > 0:13:24It's a thing that's never, never left me in all these years.
0:13:31 > 0:13:38By the morning of January 15th, the warring masses of warm and cold air left Glasgow in pieces.
0:13:40 > 0:13:4480,000 homes damaged by the winds.
0:13:47 > 0:13:50The next day, when we were watching the news and we heard
0:13:50 > 0:13:53about all the people that died, I just wanted to understand.
0:13:53 > 0:13:59"Well, how could wind be so strong, that it could blow down roofs, how it could kill people?"
0:13:59 > 0:14:03And I just became very fascinated about how the weather could be so severe
0:14:03 > 0:14:05that it could bring such devastation.
0:14:05 > 0:14:11You never think that a solid-built, as you think,
0:14:11 > 0:14:14tenement in Edinburgh,
0:14:14 > 0:14:16that this is going to happen.
0:14:16 > 0:14:19It's a freak, freak accident,
0:14:19 > 0:14:21you know,
0:14:21 > 0:14:24but put down as an act of God.
0:14:26 > 0:14:28So how CAN wind be so destructive?
0:14:28 > 0:14:31What makes it so powerful?
0:14:31 > 0:14:37We learnt from Aristotle that air currents move in part because of temperature differences,
0:14:37 > 0:14:40but there's something else.
0:14:40 > 0:14:43Air has weight,
0:14:43 > 0:14:49and it was this discovery that revolutionised our understanding of what makes the wind blow.
0:14:49 > 0:14:53Above my head at this moment, there's a lot of atmosphere,
0:14:53 > 0:14:56and it's pressing down on my head about...
0:14:56 > 0:14:59probably about half a ton on my head.
0:14:59 > 0:15:03Now, it might sometimes feel like that in the morning, but in general,
0:15:03 > 0:15:07one does not feel there's half a ton on your head, so why not?
0:15:07 > 0:15:12I mean, on my finger there's...there's a sort of huge amount of atmosphere pressing
0:15:12 > 0:15:17down on my finger, but there's also atmosphere pressing up on my finger, here, from the other side,
0:15:17 > 0:15:21so we don't feel it because it's pressing in in all directions. That's why call it pressure.
0:15:23 > 0:15:27It took a young Italian scientist to realise that air has weight.
0:15:27 > 0:15:33He wrote, memorably, "We live submerged at the bottom of an ocean of air."
0:15:33 > 0:15:39Evangelista Torricelli is an Italian experimentalist, a physicist,
0:15:39 > 0:15:42and he's working in the early 1640s.
0:15:42 > 0:15:45Torricelli's experiment was very simple,
0:15:45 > 0:15:50a glass test tube filled with mercury and a dish also filled with mercury.
0:15:50 > 0:15:54Then Torricelli turned the test tube upside down.
0:15:56 > 0:16:00Insert the bottom of the tube into a dish of mercury and stand it upright.
0:16:00 > 0:16:02Well, always... "Ptcch!" The mercury level drops.
0:16:02 > 0:16:07Some of the mercury slid down the tube, but instead of it all
0:16:07 > 0:16:11gushing out into the dish, most of it stayed in the glass column.
0:16:11 > 0:16:14Something was holding up the mercury.
0:16:14 > 0:16:19Torricelli concluded that it must be air pressure.
0:16:20 > 0:16:24The weight of the air on the surface of the mercury in the dish
0:16:24 > 0:16:28was squeezing the mercury up into the column and holding it in position.
0:16:30 > 0:16:34Torricelli noted that the column of mercury rose and fell within the tube.
0:16:34 > 0:16:37The higher the pressure, the more the column rose.
0:16:39 > 0:16:42In time, he was able to relate the movement
0:16:42 > 0:16:44of the mercury to weather patterns.
0:16:44 > 0:16:47High pressure signalled settled, fair weather.
0:16:47 > 0:16:50Low pressure warned of turbulence and storms.
0:16:50 > 0:16:56Wind is the movement of air from high pressure to low pressure.
0:16:57 > 0:17:01The air having weight feels perfectly natural to me, particularly as a sailor.
0:17:01 > 0:17:04The wind really does go from high pressure to low pressure.
0:17:04 > 0:17:06But it was Torricelli who figured it out.
0:17:06 > 0:17:09He actually invented what we think of as the barometer.
0:17:09 > 0:17:15I haven't got a barometer on this boat but I've been on enough boats where you look at it and sure enough
0:17:15 > 0:17:18the pressure's dropping, and it's dropping a lot.
0:17:18 > 0:17:20And immediately you think, "There's strong winds coming."
0:17:22 > 0:17:25Strong winds mean trouble ahead for sailors.
0:17:25 > 0:17:30But if they don't know the storm is coming, it can be disastrous.
0:17:30 > 0:17:34Storms have even changed the course of British history.
0:17:36 > 0:17:41In 1588, the Spanish Armada, in retreat from the English Navy,
0:17:41 > 0:17:44was desperate to sail round Britain's north-west coast.
0:17:49 > 0:17:54Violent westerly winds dashed them onto the rocky shores of Scotland and Ireland
0:17:54 > 0:17:57and destroyed half the entire fleet.
0:17:59 > 0:18:04The wind destroyed five times as many ships as did the English.
0:18:04 > 0:18:10Queen Elizabeth I, quick to claim divine intervention, had medals struck with the legend
0:18:10 > 0:18:14"He blew with His winds & they were scattered."
0:18:14 > 0:18:18Her archenemy Philip of Spain said, ruefully,
0:18:18 > 0:18:22"I sent the Armada against men, not the winds and waves of God."
0:18:29 > 0:18:33It was a low pressure system blowing in from the Atlantic that scuppered the Armada.
0:18:33 > 0:18:37If the barometer had been invented in 1588,
0:18:37 > 0:18:41they would have seen the mercury dropping and sailed for shelter.
0:18:43 > 0:18:48In Torricelli's day, the rise and fall of the mercury was measured in inches.
0:18:48 > 0:18:52Today, meteorologists measure pressure in millibars.
0:18:52 > 0:18:56These differences in pressure are not actually all that huge.
0:18:56 > 0:19:01The mean pressure at the surface of the Earth is a 1,000 millibars or so
0:19:01 > 0:19:06and you don't get much more than, say 30 millibars' difference either side of that.
0:19:06 > 0:19:13The swings of pressure are surprisingly small to generate all that we experience as weather.
0:19:17 > 0:19:19The variations in pressure are small,
0:19:19 > 0:19:23but they occur in a very narrow space called the troposphere.
0:19:23 > 0:19:27The troposphere is a narrow band of air,
0:19:27 > 0:19:34so thin that if the planet was the size of a beach ball and you were to wrap the beach ball in cling film,
0:19:34 > 0:19:36that's how thin the troposphere is.
0:19:36 > 0:19:41And because it's so thin and narrow, it amplifies the effect of pressure changes.
0:19:41 > 0:19:44And all the many forms of wind occur there,
0:19:44 > 0:19:47between the stratosphere and the sea.
0:19:47 > 0:19:51The air moves because the pressure is different.
0:19:51 > 0:19:54High pressure on one side, low pressure on the other,
0:19:54 > 0:19:59and so it moves, it accelerates towards the low pressure, so that's why air starts to move.
0:19:59 > 0:20:05But it can move very rapidly because of the temperature contrasts around
0:20:05 > 0:20:10and because of the rotating planet that we live on, planet Earth.
0:20:10 > 0:20:17So, wind is just air trying to move from high pressure to low pressure,
0:20:17 > 0:20:22sucked and blown around with a constant unpredictability.
0:20:22 > 0:20:25In turn, tragedy and comedy.
0:20:35 > 0:20:40We can see what this movement of air does, but the wind is invisible.
0:20:40 > 0:20:44We can't see the wind...or can we?
0:20:44 > 0:20:47We can't see the wind with our eyes of course,
0:20:47 > 0:20:52because the air's transparent, so we have to find some way of sensing the wind,
0:20:52 > 0:20:55and that means we have to bounce something off the air.
0:20:55 > 0:20:58We have to get the air to give us a signal.
0:20:58 > 0:21:03One way of doing that is to use VHF radar.
0:21:18 > 0:21:24At this facility in the Welsh hills, Professor Vaughan and his team use radar to track the wind.
0:21:29 > 0:21:33Basically, what this field of aerials does
0:21:33 > 0:21:38is it transmits a pulse of radar energy,
0:21:38 > 0:21:43and as this very loud pulse, which shouts very loudly into the atmosphere,
0:21:43 > 0:21:48and then it listens very intently for a very faint echo, and that's basically what this thing does.
0:21:53 > 0:21:56The radar tracks turbulent air.
0:21:56 > 0:22:01The returning echo provides a measurement of wind speed and direction.
0:22:01 > 0:22:07So, shouting at the heavens is not the waste of time it may once have been.
0:22:07 > 0:22:13Professor Vaughan gets answers, radar echoes that give us a picture of the winds.
0:22:13 > 0:22:18Well, what you've got here is a day's worth of measurements from the radar.
0:22:18 > 0:22:21This was a day when we would have had a front.
0:22:21 > 0:22:23That's a warm front there.
0:22:23 > 0:22:27And similarly, on this side, we would have had a cold front coming along.
0:22:27 > 0:22:31What we're looking at is a section through the troposphere,
0:22:31 > 0:22:35a constantly unfolding picture of temperature and pressure
0:22:35 > 0:22:38within the thin atmospheric membrane that wraps our planet.
0:22:38 > 0:22:43We're measuring winds, we're measuring the structure of the atmosphere, and we're
0:22:43 > 0:22:46measuring it all 24/7, and we're measuring it every two minutes.
0:22:46 > 0:22:49So that's what this thing can do for us.
0:22:50 > 0:22:53An up-to-the-minute picture for the movement of winds.
0:23:02 > 0:23:06Today, sophisticated radar reveals the wind.
0:23:08 > 0:23:13In the 17th century, merchants were desperate for ways to make the winds visible.
0:23:15 > 0:23:20The world had been opened up by great adventurers such as Columbus and Magellan.
0:23:20 > 0:23:28Now vast fortunes beckoned for those who could master the winds and rule the waves.
0:23:28 > 0:23:32Sailors needed their own picture of the wind.
0:23:32 > 0:23:36They all had very little to go on, very little indeed, and in fact,
0:23:36 > 0:23:40knowledge of wind direction and prevailing winds that we call trade winds,
0:23:40 > 0:23:46was a closely guarded secret, because if you found them and your enemy, if you like,
0:23:46 > 0:23:48didn't have them, you'd have an advantage.
0:23:49 > 0:23:54Mariners were using the trade winds to cross the great oceans.
0:23:54 > 0:23:57At the equator, the winds blow from east to west.
0:23:57 > 0:24:02But when the ships sailed north, the winds changed direction.
0:24:02 > 0:24:06The mariners needed the winds to be mapped.
0:24:06 > 0:24:11But a young British genius asked a more fundamental question about the winds.
0:24:14 > 0:24:17His name was Edmund Halley.
0:24:18 > 0:24:21He's one of the great exotics of science, no doubt about it.
0:24:21 > 0:24:23Halley has travelled quite a lot.
0:24:23 > 0:24:27He's already been on an expedition to St Helena in the South Atlantic,
0:24:27 > 0:24:34so he's travelled through the trade wind zones and some of the most complex storm systems of the world.
0:24:36 > 0:24:39On his travels, Halley made systematic observations
0:24:39 > 0:24:43of wind patterns in both the northern and southern hemispheres.
0:24:43 > 0:24:47He puzzled over the behaviour of the winds.
0:24:47 > 0:24:49Why, for instance, in the northern hemisphere,
0:24:49 > 0:24:53is the predominant wind pattern from the north to the equator,
0:24:53 > 0:24:55and the south, from the south to the equator?
0:24:55 > 0:24:59There's this great vortex somehow, in two hemispheres.
0:25:01 > 0:25:05Halley reasoned that the sun must be playing a part.
0:25:05 > 0:25:10Could it be that there was a hot spot on the Earth's surface where the sun is directly overhead?
0:25:10 > 0:25:15In the course of a day, this rotates completely around the world,
0:25:15 > 0:25:22and as it does this, you have a column of air constantly rising underneath the sun.
0:25:26 > 0:25:31Halley argued that this constantly rising column of air would move towards the poles.
0:25:31 > 0:25:35Cold air from the poles would move in to take its place.
0:25:37 > 0:25:42Halley had discovered that it's the sun that drives the circulation of air around the globe.
0:25:42 > 0:25:44Basically, it's the sun.
0:25:44 > 0:25:49We get our weather from the sun and the sun heats the equator more than it heats the pole,
0:25:49 > 0:25:52so it sets up a temperature gradient.
0:25:52 > 0:25:56This temperature gradient then drives the weather systems.
0:25:56 > 0:26:01What they're trying to do, these weather systems, is to take heat from the equator to the pole, so
0:26:01 > 0:26:06our poles are a lot warmer than they would be if there wasn't circulation
0:26:06 > 0:26:09in the atmosphere and in the ocean bringing heat in from the equator.
0:26:09 > 0:26:14Edmund Halley is chiefly remembered for discovering a comet that bears his name.
0:26:14 > 0:26:20But his discovery that the sun is the engine of the winds is just as significant.
0:26:20 > 0:26:27He basically gets it right by 1690, and I think that is utterly amazing.
0:26:29 > 0:26:36From the data he gathered from the world's oceans, Halley made detailed notes on wind direction and speed.
0:26:36 > 0:26:39The result was the first ever wind charts,
0:26:39 > 0:26:43described as "a masterpiece of practical navigation."
0:26:43 > 0:26:46His charts were detailed and accurate.
0:26:46 > 0:26:51They gave mariners and merchants THE picture of the winds that they needed.
0:26:51 > 0:26:55Halley was correct that the sun generated the circulation of air.
0:26:55 > 0:26:59But that's not enough to explain the direction of the winds.
0:26:59 > 0:27:03It would take another 50 more years and another British genius
0:27:03 > 0:27:06to understand that there was an additional force that drove the wind.
0:27:11 > 0:27:15The 18th century was the golden age of the amateur scientist.
0:27:18 > 0:27:24One such was George Hadley, so amateur no image of him exists.
0:27:24 > 0:27:29But in 1735, this unknown set out to solve the riddle of why the great
0:27:29 > 0:27:32winds of the world blew in different directions.
0:27:32 > 0:27:37Hadley accepted Halley's idea that air circulated between the poles and
0:27:37 > 0:27:42the equator, but realised that there had to be a second force at play.
0:27:42 > 0:27:46Something more than the sun was making the wind go sideways.
0:27:48 > 0:27:50And then he got it.
0:27:50 > 0:27:54Wind direction comes from the rotation of the Earth.
0:27:54 > 0:28:00The impact of this rotation on the atmosphere is known as the Coriolis force.
0:28:01 > 0:28:03The Coriolis force...
0:28:03 > 0:28:05Ahhh!
0:28:05 > 0:28:08That's such a naughty question!
0:28:08 > 0:28:11Right, OK...
0:28:11 > 0:28:13The Coriolis effect.
0:28:13 > 0:28:15It's a difficult thing to understand, I think.
0:28:15 > 0:28:18It's to the left... Oh, is it to the right?
0:28:18 > 0:28:20- I always get it wrong.- Ummm...
0:28:22 > 0:28:24Ask that to Brian Hoskins.
0:28:24 > 0:28:28If you're on a roundabout, in the park...
0:28:28 > 0:28:31..and I throw a ball at you, straight at you...
0:28:31 > 0:28:38..it'll appear to the person on the roundabout, if you like, that the ball follows a curved path.
0:28:38 > 0:28:40In fact, the ball is travelling straight.
0:28:40 > 0:28:45The Coriolis force is linked to the spinning of the Earth...
0:28:45 > 0:28:51When you're on a rotating system and you start to move, there's all sorts of different things happen and you
0:28:51 > 0:28:56tend to be flung off at right angles to the way you want to go, and that's what the Coriolis force is.
0:28:56 > 0:29:00It's saying, "OK, you want to go to that direction? I want you to go that direction."
0:29:00 > 0:29:05George Hadley could only write about the impact of the Earth's rotation on the winds.
0:29:05 > 0:29:09Professor Hoskins has found ways of showing us.
0:29:09 > 0:29:14Here we've got an old satellite dish which we've painted black,
0:29:14 > 0:29:17and if I put a ball bearing on this,
0:29:17 > 0:29:19it's just as you'd expect.
0:29:19 > 0:29:21It rolls towards the middle.
0:29:21 > 0:29:24Gravity pulls it down towards the middle, there.
0:29:24 > 0:29:29Professor Hoskins spins the dish to simulate the rotation of the Earth.
0:29:29 > 0:29:33To witness the effect of this rotation on a travelling object,
0:29:33 > 0:29:36he has set up a revolving camera above the dish.
0:29:36 > 0:29:40The ballbearing represents the air moving across the Earth's surface.
0:29:42 > 0:29:46Clearly, the ball is travelling backwards and forwards,
0:29:46 > 0:29:51but the revolving camera shows that it is going in circles as well.
0:29:51 > 0:29:54You can see from here, it's almost rotating with the dish,
0:29:54 > 0:29:59but when you look on there, what you see relative to this camera that's rotating with it,
0:29:59 > 0:30:03it's going round almost in circles, snaking on itself.
0:30:05 > 0:30:10This simple experiment demonstrates that air is spun around by the earth's rotation.
0:30:10 > 0:30:14The reason that it's complicated is because the earth is spinning
0:30:14 > 0:30:21and the spinning means you can't just take warm air from the Equator and just move it to the Poles.
0:30:27 > 0:30:33A second demonstration shows why air can't move in a straight line from the Equator to the Pole.
0:30:33 > 0:30:36Particles of aluminium are suspended in water.
0:30:36 > 0:30:41This is like a polar view of the planet and its weather.
0:30:41 > 0:30:44The centre, the pole, is cooled.
0:30:44 > 0:30:48The outside, the equator, is heated.
0:30:48 > 0:30:50Now this world revolves.
0:30:53 > 0:30:57The tiny flakes of aluminium make the invisible visible.
0:30:59 > 0:31:02For water, think air.
0:31:02 > 0:31:09Rotation spins the particles around as they journey from the warm part of the apparatus to the cold.
0:31:09 > 0:31:14Just as moving air is spun as it travels from the Equator to the Pole.
0:31:16 > 0:31:19This is the air swirling around the planet.
0:31:19 > 0:31:22The wind in a state of chaos.
0:31:25 > 0:31:27George Hadley had worked it out.
0:31:29 > 0:31:33There were not one, but two elemental forces to the wind.
0:31:36 > 0:31:41The sun, which heats the air at the Equator, and the rotation of the earth,
0:31:41 > 0:31:45which bends and twists the air as it journeys towards the Poles.
0:31:52 > 0:31:57The planet is locked into a constant struggle to balance temperature and pressure
0:31:57 > 0:31:59while subject to the forces of the earth's rotation.
0:32:02 > 0:32:05We experience these warring forces as wind.
0:32:14 > 0:32:17This is a picture of a hurricane.
0:32:17 > 0:32:21The coriolis force is spinning it in an anti-clockwise direction.
0:32:21 > 0:32:28Hurricanes are the whirlpools of the air - feeding on heat and turning it into wind energy.
0:32:28 > 0:32:34Hurricanes themselves grow over the sea because they need the energy
0:32:34 > 0:32:37that they obtain from the sea to make them grow.
0:32:37 > 0:32:42They have to have a sea temperature of at least 27 degrees Celsius.
0:32:42 > 0:32:49In the Mexican Gulf, the sea is warm - so hot it's like high octane fuel to a passing hurricane.
0:32:53 > 0:32:57In 2005, a deadly hurricane struck the United States -
0:32:57 > 0:33:02Hurricane Katrina, in which almost 2,000 people lost their lives,
0:33:02 > 0:33:06was the costliest natural disaster in US history.
0:33:11 > 0:33:17For eight days, Katrina journeyed around the Gulf of Mexico, gathering strength and wreaking havoc.
0:33:23 > 0:33:28There is another kind of rotational wind that causes havoc - the tornado.
0:33:28 > 0:33:34The formation of tornados happens in a completely different way from hurricanes.
0:33:36 > 0:33:39They're much smaller features to start off with
0:33:39 > 0:33:44and they also form out of one particular cloud which is called a cumulonimbus cloud.
0:33:46 > 0:33:51Now, if those clouds build high enough and have enough energy,
0:33:51 > 0:33:58then they will spawn what we call funnel clouds, which come out of the base of those clouds
0:33:58 > 0:34:01and once they touch the ground they become tornados.
0:34:01 > 0:34:04Britain gets lots of tornados.
0:34:04 > 0:34:06One year saw over 150.
0:34:06 > 0:34:11In relation to its area, Britain has the highest number of reported tornados in the world.
0:34:19 > 0:34:23This is the seaside resort of Bognor Regis.
0:34:23 > 0:34:29On 28 October 2000, late in the afternoon, a tornado ripped through the town.
0:34:40 > 0:34:44A tornado wind can reach speeds of 300mph.
0:34:44 > 0:34:47Anything in its path is swept aside or dashed to pieces.
0:34:47 > 0:34:52Tornados cut a swathe of destruction and terror.
0:34:52 > 0:34:57All these bricks started hitting the door and I've run out screaming. I thought the kitchen had blown up.
0:34:58 > 0:35:01No-one was hurt...
0:35:03 > 0:35:06..until the tornado reached the Riverside Caravan Centre.
0:35:08 > 0:35:12I was just leaving the park, coming down the front drive,
0:35:12 > 0:35:15and I heard a really, really loud crash.
0:35:15 > 0:35:22I looked in my mirror and I saw a tornado go across the back of the road.
0:35:22 > 0:35:27Dorothy Allwright was directly in its path.
0:35:27 > 0:35:30I saw what I thought was a bush.
0:35:30 > 0:35:36It had come out of a bin or something, just coming across the car park.
0:35:36 > 0:35:42And then all of a sudden, something...hit the caravan.
0:35:42 > 0:35:45I can only describe it as a graunching noise.
0:35:45 > 0:35:52And that must have been the chains, because the caravan was well chained down.
0:35:52 > 0:35:57The chains started to snap, and then up in the air we went.
0:35:58 > 0:36:03I can remember screaming as we were moving,
0:36:03 > 0:36:08and then all of a sudden down we must have plopped.
0:36:08 > 0:36:13The tornado ripped Dorothy's caravan from the ground, spun it in the air
0:36:13 > 0:36:16and slammed it down on top of that of her neighbour.
0:36:16 > 0:36:21Everything started to go haywire. I think panic mode came in.
0:36:21 > 0:36:22Petrified.
0:36:22 > 0:36:26I could just remember screaming, "What is happening?"
0:36:26 > 0:36:32It then went past the first caravan, did no damage to that at all,
0:36:32 > 0:36:37came across the fun-pool that we see here and picked all the water up.
0:36:37 > 0:36:40It seemed to suck it up as it went passed.
0:36:40 > 0:36:44I could see it in my car mirror throwing the water everywhere
0:36:44 > 0:36:48as it went through those caravans there and went. Just left the site.
0:36:50 > 0:36:57The emergency services rescued Dorothy, her friend and her two dogs from the mangled wreck.
0:36:57 > 0:37:03I was frightened stiff because it was something that I couldn't control.
0:37:11 > 0:37:16Tornados can spring up in a matter of minutes and can disappear just as quickly.
0:37:16 > 0:37:20Until now, they've been impossible to predict.
0:37:32 > 0:37:35But at a research establishment in Chilbolton, Hampshire,
0:37:35 > 0:37:40scientists on the frontier of weather forecasting are about to change that.
0:37:40 > 0:37:46Sensitive radar is being used to predict the formation of highly dangerous winds.
0:37:46 > 0:37:49And they're doing it in an ingenious way,
0:37:49 > 0:37:53turning a problem of 50 years ago into a solution.
0:37:55 > 0:37:59In the early days of radar development,
0:37:59 > 0:38:03progress was bedevilled by unexplained interference the boffins dubbed "angels".
0:38:03 > 0:38:07The angels, as it turned out, were birds and insects
0:38:07 > 0:38:12and that's what gave rise, half a century later, to the Chilbolton Project.
0:38:14 > 0:38:21These scientists are trying to dramatically improve forecasting by close observation of nature.
0:38:21 > 0:38:24What they're observing are insects.
0:38:25 > 0:38:27Why do we need to look at the insects?
0:38:27 > 0:38:31The insects are sitting there and they follow the wind.
0:38:31 > 0:38:35The reason they go up in in the morning is to get a free ride
0:38:35 > 0:38:38so they can follow the wind and migrate across the country.
0:38:42 > 0:38:47On 28 July 2005, the Chilbolton radar was tracking insects.
0:38:49 > 0:38:54Starting early in the morning, scientists watched a compelling story unfold on screen.
0:38:54 > 0:38:57It ended with a tornado.
0:38:57 > 0:39:04So this is the picture from the radar at 10-10.15 in the morning.
0:39:04 > 0:39:07And this is a low level sweep so it's a map over the country.
0:39:07 > 0:39:13Here's the radar in the middle, and out to about 40 or 50 kilometres in each direction
0:39:13 > 0:39:18we're getting this very low level signal here and these are associated with insects.
0:39:20 > 0:39:26The radar signal not only detects the insects, it also tracks their course.
0:39:26 > 0:39:31Insects act as tracers for the wind's direction and speed.
0:39:31 > 0:39:36These insects, you can see there's a lot of them here, so we're getting the winds,
0:39:36 > 0:39:39every 100 metres or so we're getting a velocity of the wind.
0:39:42 > 0:39:47Based on these observations, Professor Illingworth makes some predictions.
0:39:47 > 0:39:52So we've got a way of measuring the air flow using the insects.
0:39:52 > 0:39:56Can you see the insects formed in lines here?
0:39:56 > 0:40:01This is where we're expecting to get rows of clouds forming.
0:40:01 > 0:40:07By noon, storm-clouds have formed and they're heading north to Birmingham.
0:40:07 > 0:40:13Later on the satellite picture, can you see that rows of clouds have formed in that direction?
0:40:13 > 0:40:15That's from the satellite.
0:40:15 > 0:40:23Now we've left the insects far behind. This satellite image shows a developing storm.
0:40:23 > 0:40:27There's a much more power being reflected here, an enormous amount where it's white.
0:40:27 > 0:40:30That's a very intense storm.
0:40:30 > 0:40:38This is at 2.30pm, and indeed it was about 3pm, that's where the tornado developed over Birmingham.
0:40:38 > 0:40:41Oh! There goes a roof!
0:40:41 > 0:40:48In the space of five hours, what began with a swarm of insects ended with this.
0:40:48 > 0:40:51The strongest tornado to hit the UK for 30 years.
0:40:51 > 0:40:57It caused £40 million worth of damage and 19 injuries.
0:40:57 > 0:41:01By tracking insects first thing in the morning, the Chilbolton radar
0:41:01 > 0:41:05anticipated the Birmingham tornado two hours ahead of time.
0:41:06 > 0:41:11The system was only being tested that day. So no warning was given.
0:41:11 > 0:41:14Soon it will be in regular use.
0:41:15 > 0:41:21The idea is that in a couple of years the insect winds will be measured by these radars over the UK
0:41:21 > 0:41:25and at 10am in the morning on the day when it's forecast
0:41:25 > 0:41:30that thunderstorms will break out somewhere over southern England,
0:41:30 > 0:41:33this measurement of the winds will be put into the model,
0:41:33 > 0:41:38therefore you'll be able to have a couple more hours more specific warning
0:41:38 > 0:41:41of precisely where the storms are going to break out.
0:41:41 > 0:41:44'And now the shipping forecast issued by the Met Office.
0:41:44 > 0:41:47'Here are your forecasts for the next 24 hours.
0:41:47 > 0:41:53- 'Viking, variable, becoming cyclonic...'- The familiar litany of the shipping forecast.
0:41:53 > 0:41:56Required listening for those at sea.
0:41:56 > 0:42:02Wherever the wind is and no matter how strong, we will be warned using a simple scale.
0:42:02 > 0:42:04The Beaufort Scale.
0:42:08 > 0:42:13Throughout history, scientists endeavoured to give us a picture of the wind.
0:42:13 > 0:42:18Rear Admiral Sir Francis Beaufort decided to put it into words.
0:42:18 > 0:42:20If you have a method,
0:42:20 > 0:42:25an elegant method to talk about conditions,
0:42:25 > 0:42:29and you can just do it in one word or one number,
0:42:29 > 0:42:33it means if you pass the signals by flag or sound signals
0:42:33 > 0:42:37or indeed on the radio, you don't have to have long, complex conversations.
0:42:37 > 0:42:44Beaufort translated the winds in all their complexities of mood directly into mariner-speak.
0:42:48 > 0:42:54Wind force one - light air of sufficient to give steerage way.
0:42:54 > 0:42:56Force two - light breeze.
0:42:56 > 0:42:59Force three - gentle breeze,
0:42:59 > 0:43:05that in which a man of war with all sails set would go in smooth water from three to four knots.
0:43:08 > 0:43:11And finally force 12 - hurricane,
0:43:11 > 0:43:14on which no canvas can withstand.
0:43:17 > 0:43:24The Beaufort Scale became the international standard for wind measurement and remains so today.
0:43:24 > 0:43:26If I was on the radio now
0:43:26 > 0:43:33and the communication was maybe noisy or was a long way and the signal was a bit weak,
0:43:33 > 0:43:37I could pass on to somebody my local weather observation,
0:43:37 > 0:43:43and say it's gusting force four and anyone in the world would know exactly what these conditions were.
0:43:43 > 0:43:48The Beaufort scale went on to be interpreted for landlubbers.
0:43:48 > 0:43:52Moderate breeze. Wind raises dust and loose paper.
0:43:52 > 0:43:56And even appeared in France in a slightly more Gallic form.
0:43:56 > 0:44:01Force 12. Les enfants moins de six ans volent.
0:44:01 > 0:44:04Children less than six fly.
0:44:08 > 0:44:13Francis Beaufort was pivotal in putting a young Charles Darwin on board the HMS Beagle,
0:44:13 > 0:44:16captained by Robert Fitzroy.
0:44:16 > 0:44:19They set sail in the summer of 1831.
0:44:19 > 0:44:24It was a voyage that would change history.
0:44:24 > 0:44:27People often forget what that expedition was for.
0:44:27 > 0:44:34The real purpose of the expedition was for meteorological, magnetic and oceanographic purposes.
0:44:34 > 0:44:39How did the great forces of the world work together?
0:44:39 > 0:44:45Especially in those places where HMS Beagle spent so much of her time, off South America -
0:44:45 > 0:44:50some of the bleakest, most devastating seas in the world.
0:44:50 > 0:44:52What did the winds do there?
0:44:52 > 0:44:58So in many ways, the Beagle actually starts off as a geophysical and meteorological expedition.
0:44:58 > 0:45:01Evolution is a sideshow.
0:45:05 > 0:45:09As a meteorological expedition it was a triumph.
0:45:09 > 0:45:15On his return, Robert Fitzroy was chosen to head up a new, experimental government department.
0:45:15 > 0:45:18The British Meteorology Office was born,
0:45:18 > 0:45:21familiar to us as the Met Office.
0:45:21 > 0:45:28The Met Office starts as a way of coordinating all the information about weather for Britain,
0:45:28 > 0:45:35for Europe, and especially, of course, for the Navy and for the merchant marine.
0:45:35 > 0:45:41Britain was developing the biggest merchant marine on the face of the earth by the 1840s.
0:45:41 > 0:45:47Steam ships of course were coming in, but most of the traffic globally was still under sail,
0:45:47 > 0:45:54so the merchants of places like London, Liverpool, Newcastle wanted the most accurate data they could
0:45:54 > 0:46:00for how to understand what was happening basically at sea and how to make sense of it.
0:46:02 > 0:46:04Fitzroy didn't waste a minute.
0:46:04 > 0:46:10He asked ships' captains to feed-back wind and weather information from all over the globe,
0:46:10 > 0:46:13where possible using the newly invented telegraph.
0:46:13 > 0:46:15CLICKING
0:46:15 > 0:46:18And he put the data to good use.
0:46:18 > 0:46:23In 1860, Fitzroy issued the first "weather forecast".
0:46:23 > 0:46:29Within a year, weather forecasts were a daily feature of the press.
0:46:29 > 0:46:32The British public were learning to read the wind.
0:46:35 > 0:46:37Meteorology was a craze.
0:46:37 > 0:46:41Weather forecasting attracted the learned and the eccentric alike.
0:46:41 > 0:46:46None more eccentric than the inventor of the Tempest Prognosticator.
0:46:53 > 0:46:59Created by George Merryweather, it consists of 12 glass jars each containing a leech.
0:46:59 > 0:47:03At the top of each jar there is a piece of whalebone attached to a chain.
0:47:06 > 0:47:08Each chain is attached to a hammer.
0:47:08 > 0:47:13Dr Merryweather thought that leeches were sensitive to atmospheric pressure.
0:47:13 > 0:47:17If the pressure fell, they would climb from their private lagoons,
0:47:17 > 0:47:22dislodge the whalebone, pull on the chain and ring the bell.
0:47:22 > 0:47:26Merryweather sought government funding for the project
0:47:26 > 0:47:30in order to establish a national grid of leech barometers.
0:47:30 > 0:47:31He didn't get it.
0:47:34 > 0:47:38The Met Office wisely put its trust in Robert Fitzroy instead.
0:47:41 > 0:47:47Sciences like meteorology and engineering were the new articles of faith in the Victorian age.
0:47:47 > 0:47:49The wind was a spur to both.
0:47:49 > 0:47:54While science predicted the winds, engineers built structures to defy them.
0:47:57 > 0:48:00The Tay Bridge was one such structure.
0:48:00 > 0:48:07When it opened for business in June 1878, it was the longest bridge in the world, over two miles long.
0:48:07 > 0:48:11The poet William McGonegal wrote in celebration.
0:48:11 > 0:48:14Beautiful new railway bridge of the silvery Tay
0:48:14 > 0:48:18with your strong brick piers and buttresses in so grand array
0:48:18 > 0:48:25and your thirteen central girders which seem to my eye strong enough all windy storms to defy.
0:48:29 > 0:48:34The engineer who built this bridge, Thomas Bouch, believed he had the measure of the wind.
0:48:34 > 0:48:37He was wrong.
0:48:37 > 0:48:43On 28th December 1879, an almighty storm blew in from the Atlantic.
0:48:43 > 0:48:45First it hit Tiree.
0:48:47 > 0:48:53The old household was down by the shore there, very near the shore edge.
0:48:53 > 0:48:56The tide and the wind got up so much
0:48:56 > 0:48:59that eventually they had to abandon the house.
0:48:59 > 0:49:05They had to come out in the storm and make their way up the lane between the crofts here.
0:49:05 > 0:49:08They must've been on their hands and knees
0:49:08 > 0:49:14because the old grand-uncle described how, as they were coming up, a barrel flew over their head.
0:49:14 > 0:49:19And that was the same night that the Tay Bridge disaster occurred.
0:49:19 > 0:49:2228th December 1879.
0:49:28 > 0:49:33When these violent winds reached the Tay Bridge, they tore into the structure at right angles.
0:49:33 > 0:49:39The centre section collapsed, taking with it a train running along its single track.
0:49:46 > 0:49:4875 people were on board.
0:49:48 > 0:49:5175 lives were lost.
0:49:51 > 0:49:56It remains the worst structural disaster in British history.
0:49:56 > 0:50:03The bridge he so admired now in ruins, the poet McGonegal took up his pen again.
0:50:03 > 0:50:07Twas about seven o'clock at night and the wind blew with all its might
0:50:07 > 0:50:11and the rain came pouring down and the dark clouds seemed to frown
0:50:11 > 0:50:16and the demon of the air seemed to say, "I'll blow down the Bridge of Tay."
0:50:16 > 0:50:20And you can feel the wind blowing through those verses, I think, anyway.
0:50:28 > 0:50:35150 miles to the west, on Tiree, the islanders and their ancient crofts rode out the winds.
0:50:35 > 0:50:40They, and their homes, have evolved with the wind.
0:50:40 > 0:50:46The old thatched cottages, which were the double-walled, thick-walled house,
0:50:46 > 0:50:50and the thatch supported on the inner of two walls.
0:50:50 > 0:50:54When the wind strikes the outer walls,
0:50:54 > 0:51:00it's deflected up and going over the top of the roof, going around the thatch,
0:51:00 > 0:51:07it has an effect of holding the thatch down, rather than tearing at it or damaging it.
0:51:12 > 0:51:18The engineers that built the Tay Bridge could have learned much from the people of Tiree.
0:51:21 > 0:51:26Designing structures to withstand the winds has never been a simple process.
0:51:27 > 0:51:31This is the Tacoma Bridge in Washington State, USA.
0:51:31 > 0:51:36This remarkable footage captured its final moments in 1940.
0:51:44 > 0:51:46Destroyed by a 40 mile an hour wind.
0:51:46 > 0:51:49A gale, but not a hurricane.
0:52:02 > 0:52:08The Taipei 101, once the tallest building in the world, is in a Typhoon hotspot.
0:52:08 > 0:52:11It has been built to accommodate the winds.
0:52:11 > 0:52:17When they blow, the tower will bend and bounce back.
0:52:20 > 0:52:27The Tay Bridge was built to last, the Titanic was unsinkable, the Taipei Tower is typhoon-proof.
0:52:30 > 0:52:35It's not the Gods we place our faith in now, it's engineers and scientists.
0:52:35 > 0:52:38But they have their limits.
0:52:38 > 0:52:41Winds can be explained.
0:52:41 > 0:52:44Winds can be anticipated, but they can never be mastered.
0:52:45 > 0:52:50Yet the winds can be harnessed. We've done it for thousands of years.
0:52:56 > 0:53:01Now its awesome power is attracting the attention of an energy-hungry world.
0:53:01 > 0:53:03Britain has abundant supplies.
0:53:05 > 0:53:09Modern alchemists are turning wind into energy.
0:53:09 > 0:53:14It is sort of magic. When you look at a cold wind and it turns into a hot fire.
0:53:14 > 0:53:17Its marvellous. Its engineering at its best.
0:53:19 > 0:53:24Gordon Proven has been designing and making wind turbines for nearly 30 years.
0:53:24 > 0:53:29His factory in Scotland makes 20 wind turbines a week with orders from all over the world.
0:53:32 > 0:53:35It is relatively simple, but complicated to make work.
0:53:38 > 0:53:41We have wings, like the wings of an aeroplane, which rotate.
0:53:43 > 0:53:46They produce a forward force,
0:53:46 > 0:53:50so they'll rotate just like a kids windmill at the fairground.
0:53:50 > 0:53:56Then we have a shaft that goes to a direct drive generator.
0:53:57 > 0:54:03We have two plates of magnets which rotate past our windings of copper.
0:54:03 > 0:54:07When you pass a magnet past copper, you produce an electric current.
0:54:07 > 0:54:09We take that current out,
0:54:09 > 0:54:14put it into some electronics, and feed it into the grid. Easy.
0:54:18 > 0:54:24The first electricity-producing wind turbine was invented over 100 years ago.
0:54:24 > 0:54:30It was a remarkable Scottish engineer, James Blyth, who led this energy revolution.
0:54:30 > 0:54:36In 1887, Blyth successfully generated electricity from a wind turbine.
0:54:36 > 0:54:38It was a world first.
0:54:40 > 0:54:45This photograph shows his experimental turbines in front of his cottage.
0:54:48 > 0:54:52This one shows the turbine he built for the Montrose lunatic asylum.
0:54:52 > 0:54:57It generated 10 horsepower - enough to light the entire building -
0:54:57 > 0:55:00and ran for nearly 30 years.
0:55:00 > 0:55:03This is Professor Blyth's machine.
0:55:03 > 0:55:07It is giant. These things are about 4 metres in height.
0:55:07 > 0:55:12My calculations indicate that it was about 2% efficient.
0:55:12 > 0:55:17He's got too many cups. One cup is shading the other one.
0:55:17 > 0:55:21He's the first guy in the world to make an electricity-producing wind turbine,
0:55:21 > 0:55:26even though it's only a twentieth of the efficiency of our modern machines.
0:55:26 > 0:55:30It got to work and it lasted 27 years, which is fantastic.
0:55:34 > 0:55:37And its thanks to the pioneering spirit of James Blyth
0:55:37 > 0:55:43that the islanders of Tiree can harvest the wind - their most abundant asset.
0:55:43 > 0:55:48At the eastern end of the island they're planning to erect their own wind turbine.
0:55:48 > 0:55:51We've spent the last three or four years
0:55:51 > 0:55:54pulling together a plan to erect a single wind turbine,
0:55:54 > 0:55:57which will be around 900 kilowatts,
0:55:57 > 0:55:59and will be based on the far east of the island.
0:55:59 > 0:56:04And that will generate, hopefully, depending on if we're lucky,
0:56:04 > 0:56:08around £300,000 of income for the community each year.
0:56:09 > 0:56:13It's definitely something that makes life, at times here, challenging.
0:56:13 > 0:56:19To actually get a payback and use a natural resource that is completely renewable and sustainable,
0:56:19 > 0:56:22I think everyone likes the idea.
0:56:25 > 0:56:28The wind that has scoured this bleak land for thousands of years
0:56:28 > 0:56:32may one day earn this community thousand of pounds a year.
0:56:32 > 0:56:36Money galore. It buys a lot of whisky.
0:56:39 > 0:56:41So now we know.
0:56:41 > 0:56:44We know what the wind is and what causes it.
0:56:44 > 0:56:52We have weather forecasts on the TV, on the radio, on our laptops, even on our telephones.
0:56:52 > 0:56:56Our obsession with the weather is what makes us British.
0:56:56 > 0:56:59No, British weather is what makes us British.
0:56:59 > 0:57:02POP MUSIC PLAYS
0:57:08 > 0:57:13Never knowing what to wear, when to barbecue, vest or no vest - never prepared.
0:57:16 > 0:57:22The winds that blow on to our shores will bring good and ill in equal measure and we'll never know which.
0:57:22 > 0:57:25Sometimes both.
0:57:25 > 0:57:27A mixed blessing.
0:57:27 > 0:57:30Our attitude to the wind is ambivalent at the moment.
0:57:30 > 0:57:36We're living this life - in and out of aeroplanes, taxis, cars and trains, then off to work.
0:57:36 > 0:57:39The only time we might get engaged with the wind is
0:57:39 > 0:57:43when our umbrella goes inside out or your hair gets messed up.
0:57:43 > 0:57:46I'm not sure we do respect the wind enough.
0:57:46 > 0:57:49I mean, it's an incredibly powerful force of nature
0:57:49 > 0:57:52and those of us that live in Britain,
0:57:52 > 0:57:58I don't think we offer enough respect to the great winds of the earth.