Will It Snow?

:00:09. > :00:12.It's the first week of November, and we have climbed up above the

:00:12. > :00:17.village of Braemar in the Scottish Highlands. We are at about 1300

:00:17. > :00:21.feet, it seemed a good place to join the conversation that's

:00:21. > :00:28.already gearing up around the country, on what sort of winter we

:00:28. > :00:32.might have in store. Why are we here? As well as being incredibly

:00:32. > :00:39.blustery, Braemar holds the record for the lowest temperature ever

:00:40. > :00:44.recorded in the UK, a minus 27.2 degrees Celsius. Where better to

:00:44. > :00:49.ask are we heading for another big freeze. We will be looking at the

:00:49. > :00:53.latest science and cutting edge weather forecast. What about our

:00:53. > :00:56.airports, our supermarkets, energy suppliers and health service. Do

:00:56. > :01:00.they think they have another hard winter coming. And most importantly,

:01:00. > :01:10.are they prepared for it? Over the next hour, what we seek to answer

:01:10. > :01:18.

:01:18. > :01:23.is really just one simple question, Remember this? Motorists gridlocked

:01:23. > :01:28.on icey roads, trains stranded, and thousands of flights cancelled.

:01:28. > :01:34.Across the UK, we did battle with the wrong type of snow, killer ice,

:01:34. > :01:38.and an estimated cost to the economy of over �200 million per

:01:38. > :01:43.day in transport disruption alone. December was the coldest month for

:01:43. > :01:47.over a century.With the mild weather across the UK today, it is

:01:48. > :01:57.hard to cast our minds back to just nine months ago, when we emerged

:01:58. > :02:02.

:02:02. > :02:05.from what journalists dubbed, "Snomageddon". Look at that, the

:02:06. > :02:10.very first snow of the British winter, I knew we had come to the

:02:10. > :02:14.right place, and this is Alex Hill, at the frontline of Scottish

:02:14. > :02:18.meteorology for how many years? When you see snow like that, is

:02:19. > :02:22.this a science that winter is well and truly on its way. Is this the

:02:22. > :02:26.first snow of the year? The first snow was a few weeks back, it is

:02:26. > :02:33.all gone, apart from the little patch we saw there. We had a cold

:02:33. > :02:38.northerly for a while, very heavy showers, that ploanks a few

:02:38. > :02:43.centimeters of snow - plonks a few centimeters of snow around the

:02:43. > :02:47.place. What are we looking at? the next few weeks and days the

:02:47. > :02:50.chances of snow are very, very small. In your 37 years of

:02:50. > :02:54.experience, had you seen winters like the ones that we have had the

:02:54. > :03:02.last couple of years? I think that is the curiosity, everybody got

:03:03. > :03:05.into a kind of paddy about it, and yes, I think 2010/11 was a

:03:05. > :03:08.particularly chilly winter, but it lasted just for November and

:03:08. > :03:13.December. By the time you were into January and February, the

:03:13. > :03:17.temperatures were getting milder and milder. Has it been an exciting

:03:17. > :03:21.time for meteorologist? Exciting, certainly, yes, stressful,

:03:21. > :03:27.certainly. But it makes people realise, perhaps, that weather has

:03:27. > :03:34.much more impact than you imagine on your day-to-day life.

:03:34. > :03:38.The Met Office has one of its 450 weather stations up here at Braemar.

:03:38. > :03:44.They know from bitter experience, it is not too early to be on snow

:03:44. > :03:49.alert. So what has been making our winters so unseasonably cold

:03:49. > :03:53.recently. Can we blame a particular type of weather system. Can

:03:53. > :03:57.scientists predict how much snow is going to small? And what about the

:03:57. > :04:02.forecasters, can we rely on them to see another big freeze heading our

:04:02. > :04:05.way? I have to say, it is quite a relief

:04:05. > :04:09.to sit down. We have been tearing around the country for the last

:04:09. > :04:17.week, trying to establish whether we have got another truly horrible

:04:17. > :04:22.winter heading our way. It does seem a little bit ridiculous. We

:04:22. > :04:25.are just emerging from the warmest October on record. We are at the

:04:25. > :04:29.BBC headquarters in Glasgow, and look, we have an open roof above us.

:04:29. > :04:34.It is not exactly sunny, but it is actually quite warm. Do you think

:04:34. > :04:37.we are all getting into a bit of a panic about nothing? It is

:04:37. > :04:41.unseasonably warm, but this is a conversation we do love to have in

:04:41. > :04:44.the UK. I think it is a scientific question, the headlines have

:04:44. > :04:48.already started. This is one from one newspaper that Britain faces an

:04:48. > :04:51.early big freeze. Science should be able to answer that question,

:04:51. > :04:56.already, earlier this week in the US there was a monster snowfall,

:04:56. > :05:00.and we did see the type of chaos we saw last year, with airports being

:05:00. > :05:05.closed down. People are even saying could we be entering into a mini-

:05:05. > :05:11.Ice Age. The thing is, we have got all this technology at our

:05:11. > :05:14.fingertips, satellites in the sky, data pouring in, surely science

:05:14. > :05:18.should be able to tell us whether or not it will snow? Climate

:05:18. > :05:22.science is an enormous field. There is a bewildering amount of data out

:05:22. > :05:24.there. What I want to find out is what are the limits of that science.

:05:24. > :05:29.How much can the data actually tell us about what the weather will do

:05:29. > :05:33.in the next few weeks. Let's also not forget that there was a time,

:05:33. > :05:37.when we didn't have satellites, we didn't have all this technology at

:05:37. > :05:41.our fingertips. Can the natural world actually give us any sort of

:05:42. > :05:44.clue as to what sort of winter we are going to have? Later in the

:05:44. > :05:48.programme, Alys Fowler is going to be investigating that for us. She's

:05:48. > :05:53.heading out into the countryside to see what the natural world might or

:05:53. > :05:56.might not be able to tell us about the coming winter. But our

:05:56. > :06:04.investigation started right at the frontline of meteorology, down

:06:04. > :06:09.south. Britain's weather is volatile and

:06:09. > :06:13.ever-changing, and we are famously obsessed with it. The people who do

:06:13. > :06:23.daily battle with our unpredictable weather, and indeed with our

:06:23. > :06:23.

:06:23. > :06:28.expectations, work here. At the Met Office headquarters. The Met Office

:06:28. > :06:36.works around the clock, 365 days a year. Providing forecast data for

:06:36. > :06:40.over 300 locations in the UK. But predicting the weather is a

:06:40. > :06:44.trickery business, involving superxuet computers, expert

:06:44. > :06:47.meteorologist, and data collected from all over the planet, including

:06:47. > :06:51.the deep ocean and outer space. If you have all these thousands and

:06:51. > :06:55.thousands of observations coming in, you have got all these computers

:06:55. > :07:01.and computer models doing all this work, and all these specialists

:07:01. > :07:04.here, why is it so difficult to get a forecast absolutely accurate?

:07:04. > :07:10.is difficult, but we have successes as well. You have got to remember

:07:10. > :07:13.last winter the snow forecast for the shert period were excellently

:07:13. > :07:18.forecast. We had the Heathrow forecast, we do very well. There

:07:18. > :07:22.are some difficulty in forecasting the weather. As we head into winter

:07:22. > :07:26.there is a lot at stake. Farmers risk loss of livestock, local

:07:26. > :07:29.authorities need to know when to grit the roads, and any of us

:07:29. > :07:34.wanting to travel are desperate to know what's in store.

:07:34. > :07:42.But the truth is, predicting the weather day by day is still the

:07:42. > :07:45.only way to promise accuracy. This model is created by your

:07:45. > :07:49.supercomputer, from all those millions of observations that are

:07:49. > :07:53.coming in from around the globe? That is absolutely right. It shows

:07:53. > :07:57.band of rain coming across Ireland. When the forecasters, the chief

:07:57. > :08:01.forecaster, one of his jobs is to check out the reliability of that

:08:01. > :08:06.forecast. As you can see here, around about the same time, this is

:08:06. > :08:09.actual rainfall over Ireland. So the front, coming in from the west,

:08:09. > :08:12.the model prediction and the actual position of the rain on the radar

:08:12. > :08:16.is actually fairly good. We know categorically what is happening now,

:08:16. > :08:19.how about what's going to happen tomorrow, how do you then use that

:08:19. > :08:22.information? Absolutely right. We have to know what's happening now,

:08:22. > :08:26.whether the model is exactly correct before making a prediction.

:08:26. > :08:30.Once we know what's happening now through the Oakss, the models and

:08:30. > :08:33.looking at everything, we can make a more confident statement about

:08:33. > :08:37.what will happen tomorrow. Over the coming weeks, what will you be

:08:37. > :08:41.looking for to tell you that it is going to snow? One of the most

:08:41. > :08:45.important things is to look at the temperature of the air mass. It is

:08:45. > :08:49.not just the, believe it or not, it is not just the temperature of the

:08:49. > :08:56.air mass, it is the dryness, as that rainfalls into dry air, it

:08:56. > :09:01.cools the air by a thing called evapive cooling. This is two very

:09:01. > :09:04.important factor whrs it will be rain or snow. Despite a

:09:04. > :09:08.supercomputer performing a billion calculation per second, predicting

:09:08. > :09:12.whether it will snow, even as far ahead as this coming weeks, is

:09:12. > :09:17.pushing the limits of what they can say with confidence. At this point,

:09:17. > :09:19.could you say, hand on heart, whether it will snow this winter?

:09:19. > :09:23.It will snow somewhere in the British Isles this winter. Anyone

:09:23. > :09:28.who turns around and says in the 25th of December, which happens to

:09:28. > :09:36.be Christmas day, it will snow, is, quit he frankly a fool.The

:09:36. > :09:41.Office does look further ahead. Adam leads a team that looks both

:09:41. > :09:51.at seasonal prediction and how climate on a long-term and global

:09:51. > :09:52.

:09:52. > :09:57.scale affects the weather we experience in the UK.

:09:57. > :10:01.Why is it so hard to make an accurate long-term forecast?

:10:01. > :10:04.reason is we live in the mid- latitudes where there are lots of

:10:04. > :10:08.storms and vairability. This is part of the reason why British

:10:08. > :10:13.people are so obsessed with the weather and like to criticise

:10:13. > :10:18.weather forecasters also at times. Why is it so difficult to nail your

:10:18. > :10:23.flag to the mast asay it will snow in February? - and say it will snow

:10:23. > :10:28.in February? Because, basically, atmospheric chaos is a real

:10:28. > :10:31.phenomenon. The old adage that the butterfly flaps its wings and sets

:10:31. > :10:34.off a storm in the rest of the world, a small thing today could

:10:35. > :10:40.change the detail in the outcome, you can't nail your flag to the

:10:40. > :10:45.mast and be deterministic and specific.

:10:45. > :10:52.Most people know that Britain is warming than it should be for its

:10:52. > :10:56.latitude, that is thanks to two things. The first is thermohaline

:10:56. > :11:01.circulation, or THC, a massive movement of water in the oceans

:11:01. > :11:05.around the world. But some people have raised concerns that the

:11:05. > :11:11.melting of the northern icecap could affect the THC, and maybe

:11:11. > :11:16.even shut it down. And this would make our weather significantly

:11:16. > :11:20.colder. Research continues. But the second and best understood governor

:11:20. > :11:27.of our winter weather here in Britain, is, of course, the

:11:27. > :11:30.jetstream, which feedz us with warm, moist air, from the west. But it is

:11:30. > :11:35.an unpredictable beast, and sometimes gets snoked off course.

:11:35. > :11:39.Just a single air current - knocked off course. A single air current

:11:39. > :11:42.from Siberia can be enough to disrupt the air stream's warming

:11:42. > :11:49.influence. Meteorologists call this a blocking pattern, and such a

:11:49. > :11:53.weather system was responsible for last year's big freeze. It is clear,

:11:53. > :11:58.even with thousands of bits of data, coming in every day, from every

:11:58. > :12:02.corner of the globe, it is really difficult to forecast when snow

:12:02. > :12:06.might fall here in the UK. But before they can worry about

:12:06. > :12:14.predicting when snow will fall, scientists have to understand how

:12:14. > :12:23.it is made. The big question for me is what

:12:23. > :12:28.triggers is a huge snowfall. - triggers a huge snowfall. We snow

:12:28. > :12:36.snow is made inside clouds like rain. But know is not just frozen

:12:36. > :12:39.rain. What is it then? I'm hoping the Centre for

:12:39. > :12:44.Atmospheric Science, here at the University of Manchester will have

:12:44. > :12:48.some answers for me. The biggest problem in predicting snowfall is

:12:48. > :12:57.that whilst we know if it is going to snow, we have no real idea what

:12:57. > :13:02.type of snow is coming, and how fast it is going to fall.

:13:02. > :13:07.High in the clouds, there are millions of tiny supercold water

:13:07. > :13:10.droplets, to make snow, first you need some of these droplets to

:13:10. > :13:15.evaporate into water vapour. This vapour then drifts through the

:13:15. > :13:20.cloud until it makes contact with something, maybe a speck of dust,

:13:20. > :13:26.or some other bit of matter that triggers the water vapour molecules

:13:26. > :13:32.into forming ice crystals. This process is called seeding. When ice

:13:32. > :13:35.crystals clump together, they can make a snowflake.

:13:35. > :13:41.But what scientists haven't been able to work out is just how much

:13:41. > :13:49.snow a cloud will produce. Inside there is a piece of kit which is

:13:49. > :13:54.set to change that. This cylinder replicates the conditions needed to

:13:54. > :14:00.make snow. It can literally conjure a flurry of snow out of thin air.

:14:00. > :14:03.Well, technically, out of supercooled clouds. This is a cloud

:14:03. > :14:07.chamber, this is where you make clouds here in the basement, how

:14:07. > :14:14.does it actually work? It spans three floors of this building. And

:14:14. > :14:22.we make clouds using this giant kettle, the steam travels up this

:14:22. > :14:27.pipe into the cloud chamber, and contenses to form water droplets,

:14:27. > :14:32.later on we can nucleate this cloud and seed it and make it into ice.

:14:32. > :14:41.They make it look simple, but don't be fooled. It has taken years of

:14:41. > :14:45.research to take what happens in nature high up in the atmosphere.

:14:46. > :14:50.You can get straight snow out of there. That has fallen from the 10m

:14:50. > :14:55.height, from ice crystals and lands as snow. That is exactly it.

:14:55. > :15:03.But what is seeding, exactly? And how does it create the ice crystals

:15:03. > :15:09.you need to make snow. We know that pure water freezes at zero degrees

:15:09. > :15:14.Celsius, but the water in these test-tubes is 11 degrees below zero

:15:14. > :15:18.and yet it is still liquid. For ice crystals to form, the supercooled

:15:18. > :15:24.water needs to latch on to something around which it can grow.

:15:25. > :15:29.In this case it is a single ice crystal that triggers the chain

:15:29. > :15:36.reaction of lots more being able to form. Another more dramatic example

:15:36. > :15:44.uses a supercooled bubble of soppy water, and a tiny bit of ice

:15:44. > :15:46.hitting it, crystals rapidly appear. But it is what happens to these

:15:46. > :15:54.tiny crystals after they have formed that determines if it is

:15:54. > :15:59.going to snow. And how much snow will fall. Paul is working on what

:15:59. > :16:03.he hopes will be a new way to predict snowfall more accurately.

:16:03. > :16:06.These are the crystals being formed inside the cloud chamber, what are

:16:06. > :16:11.we actually looking at? We are looking at the different ice

:16:11. > :16:16.crystals that have fallen out. At this temperature, minus 15, they

:16:16. > :16:21.are all the same type of ice crystal, the six-pointed shape, hex

:16:21. > :16:25.ago national plates. Some of them, more than one ice crystal, stuck

:16:25. > :16:28.together, there is two there on that one. This is two crystals that

:16:28. > :16:33.have clumped together? That's right. That is the beginning of the

:16:33. > :16:39.formation of a snowflake? Basically. What actually determines whether a

:16:39. > :16:45.snowflake is going to fall? simply, it is to do with its weight,

:16:45. > :16:49.and how much area it takes up, because the area determines the air

:16:49. > :16:53.resistance. Some snowflakes have large surface area, not much mass

:16:54. > :16:57.and fall very slowly. Some snowflakes are the opposite and

:16:57. > :17:01.small much quicker. This is how you work out what are the conditions,

:17:01. > :17:11.in a cloud, that determine whether it will snow or not? That's right,

:17:11. > :17:12.

:17:12. > :17:16.it happens at different rates and different temperatures. It is early

:17:16. > :17:21.days for this study. But it could lead to weather forecasters being

:17:21. > :17:25.able to accurately predict snowfall. And that could help prevent the

:17:25. > :17:35.kind of chaos that sees airports close and motorists stuck in

:17:35. > :17:40.snowdrifts. Last winter may have felt very long

:17:40. > :17:45.and very cold. But it wasn't the hardest winter that Britain has

:17:45. > :17:53.experienced in recent times. Some of you may remember 1963, the worst

:17:53. > :17:57.winter in living memory. The snow started on Boxing Day, and

:17:57. > :18:01.the big freeze lasted until March. Thousands of miles of roads,

:18:02. > :18:06.throughout Britain, became impassable. Milk froze, water pipes

:18:06. > :18:10.cracked, and fresh water had to be rationed.

:18:10. > :18:15.Tanks were set up in the street, but even they froze up, and you

:18:15. > :18:18.needed hot water to thaw out the tap to get cold water to make hot

:18:18. > :18:25.water with. The cause, pretty much the same kind of Siberian weather

:18:25. > :18:29.that hit us last year. On December 21st, this Siberian anticyclone

:18:30. > :18:34.started to move in our direction. But the west Atlantic winds that

:18:34. > :18:39.usually keep it at bay, suddenly weakened, and the Siberian

:18:39. > :18:46.anticyclone moved right across to us. By December 22nd, it had hit us,

:18:46. > :18:50.it was here, and the big freeze had begun.

:18:50. > :18:56.The second blow, hundreds of towns and villages were cut off. For some,

:18:56. > :19:02.the only way to survive was to walk miles in the snow. Others had to be

:19:02. > :19:08.rescued. For over two months, the freezing air sat over the UK, a

:19:08. > :19:14.classic blocking pattern, but on an even bigger scale than our winter

:19:14. > :19:24.of 2010. And for 2011, well people are already preparing for the worst,

:19:24. > :19:26.

:19:26. > :19:31.especially out in the countryside. That was pretty impressive! Not bad,

:19:31. > :19:35.through the gate first time. I have popped back home to Monmouthshire

:19:35. > :19:39.in South Wales to see what plans farmers are making to survive the

:19:39. > :19:45.worst that nature can throw at us, both for themselves, and, of course,

:19:45. > :19:49.their livestock. Not far from here I have a small

:19:49. > :19:53.holding, just over four acres, I have a couple of pig, ten ewes and

:19:53. > :19:59.some chickens and ducks and things. When the hard weather hits, it is a

:19:59. > :20:03.bit of a nightmare. All the pipes freeze, the water troughs freeze,

:20:03. > :20:08.everything needs feeding twice as much as it does normally.

:20:08. > :20:12.Everything takes an awful lot more time, but, imagine if you have a

:20:12. > :20:17.farm, several hundred acres, and your whole livelihood depends on

:20:17. > :20:26.the health of your livestock, or the state of your fields. Then, you

:20:26. > :20:33.really know the meaning of hard weather. This sheep farm sond by

:20:33. > :20:36.friends of mine, Jim and Kate Beavan. The farm has been in the

:20:36. > :20:44.family for four generation, they have a thousand sheep, 80 cows and

:20:44. > :20:48.all sorts of other animals. Whatever the weather, these animals

:20:48. > :20:52.need feeding, that is a big problem if their food is frozen under a

:20:52. > :20:56.foot of snow. If they are pregnant, and they have got lambs inside them,

:20:56. > :20:59.then, of course, if they don't get enough food, then the lambs will

:21:00. > :21:05.suffer. The other problem s when you are rooting around in the snow,

:21:05. > :21:08.as a sheep, and you are looking for food, you are using up energy, and

:21:08. > :21:11.keeping warm in the low temperatures, that is using up

:21:11. > :21:17.energy, they need more food. It is a vicious cycle. You go through an

:21:17. > :21:22.awful lot of food when the weather is cold. What have you done to

:21:22. > :21:27.mitigate that? We have planted approximately 30 acres of root

:21:27. > :21:30.crops, so they grow in, there is a swift variety of kale that grows

:21:30. > :21:34.about that high, takes a lot of snow to cover that. Do you feel

:21:34. > :21:40.prepared, do you think that if the worst happens you can cope? Yep. We

:21:40. > :21:48.have had a good harvest this year, we have some good root crops.

:21:48. > :21:53.we have down to a tee, water is the biggest problem, that is a problem,

:21:53. > :21:56.at lambing time it is a problem. You think should we lamb earlier or

:21:56. > :22:03.later, it could come in January or March, you don't know when it is

:22:03. > :22:07.going to come. Jim and Kate have been farming for

:22:07. > :22:12.a long time. As much as they will listen to the forecasts, they have

:22:12. > :22:15.learned the hard way that there is only so much a weather report can

:22:15. > :22:20.tell them. I can't see how it can work for months and months in

:22:20. > :22:24.advance. When they have got a week or a fortnight, I can see that. But

:22:24. > :22:28.when they say we will have heavy snow in January and February, I

:22:28. > :22:32.can't see it in my mind, I can't work out how they can do that.

:22:33. > :22:36.Short-term they have it bang on. Today I looked at it yesterday, we

:22:36. > :22:42.knew exactly when the rain would start and finish, it was pretty

:22:42. > :22:45.much bang on. The cows were lying down, we knew it would rain. Long-

:22:45. > :22:50.term, as I remember, they said it would be a boiling hot summer, and

:22:50. > :22:53.we didn't get it. What do you reckon, is it going to snow this

:22:53. > :22:57.year? We will have t but I don't think we will have the quantities

:22:57. > :23:02.that people are saying. I honestly don't. I said three years on the

:23:02. > :23:05.trot, no. I have got the sledges out!

:23:05. > :23:13.There you are, that is the definitive winter forecast from the

:23:13. > :23:18.Beavans. Of course, weather forecasting is

:23:18. > :23:23.hardly a new art. Gardener, Alys Fowler, has been tracking down some

:23:23. > :23:30.of the more eccentric methods of divining whether a freeze is on its

:23:30. > :23:34.way. Before modern weather forecasting,

:23:34. > :23:38.we looked to nature to tell us what to expect from the weather. Not

:23:38. > :23:43.just day-to-day, but for weeks and months ahead. Bits of that

:23:43. > :23:48.knowledge, known as weatherlore, survive even today.

:23:49. > :23:54.We have all heard the saying, "red sky at night, shepherd's delight,

:23:54. > :24:00.red sky in the morning, shepherd's warning", is there any truth in it.

:24:00. > :24:02.It turns out it is, a red sky at night tells us the setting sun is

:24:02. > :24:05.sending light through dust particles, this usually means high

:24:05. > :24:10.pressure and stable air from the west. Good weather is heading our

:24:10. > :24:14.way. If the morning sky is red, it can

:24:14. > :24:19.indicate lots of water in the atmosphere. And if it is cold

:24:19. > :24:25.enough, that can produce snow. But what about our big question,

:24:25. > :24:28.will it snow? What weatherlore predicts harsh

:24:28. > :24:37.winters? This is one of my favourite ones,

:24:37. > :24:40.onions skined very thin, milds a winter coming in, onion skin thick

:24:40. > :24:45.and rough, winter is coming in rough. This is Spanish one, not

:24:45. > :24:49.that accurate! But, of course, vegtables harvested

:24:49. > :24:51.in August simply cannot tell us anything about the winter ahead. So

:24:51. > :24:56.if onion weatherlore is out, what is in?

:24:56. > :25:01.They say if the qirl has a really bushy tail, - the squirrel has a

:25:01. > :25:05.really bushy tail, it will be a cold winter. Surely it is just that

:25:05. > :25:09.they fluff up their tails to stay warm!

:25:09. > :25:14.Here is another, thunder in September means snow is six weeks

:25:14. > :25:18.away, also meaning less. Why did saying like this come about? Most

:25:18. > :25:23.likely it is because trying to plan for bad weather was even more

:25:23. > :25:28.important to our ancestors than to us today.

:25:28. > :25:33.Lots of berries, particularly on the rowan or holly, is supposed to

:25:33. > :25:37.indicate a hard winter is coming, this is a really good berry year.

:25:37. > :25:41.But, alas, I haven't been able to find a scientist who can stand this

:25:41. > :25:45.one up for me either. Although, I'm sure this berry bounty will be

:25:45. > :25:50.snapped up in weeks to come. But there is one piece of

:25:50. > :25:57.weatherlore that may be able to help us. Bob Elliot from the RSPB

:25:57. > :26:02.is the man in the know. What about the old wives tale that

:26:02. > :26:05.the swan brings winter on its wings? I think it is a lovely

:26:05. > :26:09.saying, we have grown up with it. What is true is they are fleeing

:26:09. > :26:13.the colder weather, they are bringing the winter with them.

:26:13. > :26:23.there a particular swan we should be looking out for? A very special

:26:23. > :26:23.

:26:23. > :26:27.species called the Buick swan, nest ing in Siberia - testing in Siberia,

:26:27. > :26:32.in early November there is a huge migration of these birds. Most

:26:32. > :26:35.arrived all in one go over a couple of days. Very soon after that we

:26:35. > :26:39.had snowy weather, they were fleeing from the extreme weather

:26:39. > :26:44.conditions, this snow. When the swan falls, the snowfalls?

:26:44. > :26:48.Precisely. It is the first week of November,

:26:48. > :26:52.and they haven't arrived yet, so I think we are OK for now

:26:52. > :26:58.I would like to believe that swans really can give us a heads up on

:26:59. > :27:05.the weather. But when the big freeze descends, it is the smaller

:27:05. > :27:11.birds that inhabit our gardens that need our help.

:27:12. > :27:16.Bob has some tips for us? What they try to do is recreate their food

:27:16. > :27:21.supplies in the gardens. Fruit, for the fruit-eating species, like the

:27:21. > :27:27.thrushes, put out windfall apples, if you have some spare rotten

:27:27. > :27:32.apples from the kitchen, they can be really beneficial for them.

:27:32. > :27:39.they need more high-protien food, an apple is a lot of sugar? It is,

:27:39. > :27:44.they need seeds, high protien, they need fatty foods, good old standard

:27:44. > :27:48.peanuts have a lot of fat in it, they zone in on those. They will

:27:48. > :27:53.know where they are, these feeding stations in people's gardens, they

:27:53. > :27:56.know where it is. It is in their winter territories, and feed on

:27:56. > :28:01.them communally it is a special sight. Where birds in the summer,

:28:01. > :28:05.they are all breeding, separate in their own territories. Here, in the

:28:05. > :28:08.winter, during snowy weather in particular, competition is pretty

:28:09. > :28:12.fierce, but if there is enough food to go round, generally all the

:28:12. > :28:17.different species will be able to find their particular food needs.

:28:17. > :28:21.sometimes put out warm water for the birds, is it a good idea?

:28:21. > :28:25.a good idea, temperatures will drop eventually so overnight they will

:28:25. > :28:29.freeze. Try anything from a ping pong ball, one of my friends has

:28:29. > :28:35.loads of these yellow plastic ducks that you have in the bath, floating

:28:35. > :28:39.around in the water bowl outside, if it is a bit breezy the motion of

:28:39. > :28:43.the objects will keep the ice from forming, at least enough for the

:28:43. > :28:48.birds in the morning to drink. It is not just drinking it is bathing

:28:48. > :28:52.that is incredibly important for them. Their feathers have been to

:28:52. > :28:55.be in absolute tip top condition to survive the bad weather. They need

:28:55. > :28:59.to be insulated properly, they can only do that if they are clean.

:28:59. > :29:03.can't imagine having a bath on a cold day, I can see it makes sense.

:29:03. > :29:07.So there is lots we can do to help wildlife survive the snow. We are

:29:07. > :29:13.helped by the fact that city gardens tend to be warmer. It is

:29:13. > :29:17.called the urban heat island effect. Gardens in big cities like London,

:29:17. > :29:23.Birmingham and Manchester can be as much as five degrees warmer than

:29:23. > :29:29.rural counterparts. All that brick and concrete is

:29:29. > :29:32.great at stopping the heat escaping. But for prolonged cold spells, even

:29:32. > :29:37.our urban gardens fall victim to the weather.

:29:37. > :29:41.We just don't know what this winter will bring, but we do know, from

:29:41. > :29:45.bitter experience, how damaging it can be for the garden and the

:29:45. > :29:55.wildlife. So wrap up your plants, put out some extra bird food, then,

:29:55. > :29:58.

:29:58. > :30:01.if it does snow, at least you can Alys's advice will help our

:30:01. > :30:04.wildlife through a tough winter. What about us? Are the

:30:04. > :30:12.organisations we rely on to keep us warm and healthy ready for the snow

:30:12. > :30:17.if it comes? It looks like the major utilities

:30:17. > :30:21.companies are preparing for the worst. Hundreds of people have had

:30:21. > :30:26.their gas supplies limited as the National Grid tries to cope with

:30:26. > :30:29.the demand from home owners. National Grid has been forced to

:30:29. > :30:34.issue a warning that demand for energy is threatening to outstrip

:30:34. > :30:39.supplies. Only the second time they have ever had to do so.

:30:39. > :30:49.When a cold snap bites, our demand for energy can jump 30%, as we turn

:30:49. > :30:50.

:30:50. > :30:56.up the heating. It is not just about energy, winter

:30:56. > :31:01.places an added burden on the NHS, due to people injuring themselves

:31:01. > :31:06.on snow and ice. I slipped and fell with my dog, I had a stick but I

:31:06. > :31:11.fell on the ice. Size is always a nightmare, people call - ice is

:31:11. > :31:16.always a nightmare, people fall over and break things like wrists

:31:16. > :31:22.and ankles. It can cost an extra �40 billion in treatment costs. The

:31:22. > :31:27.Met Office has arranged to send out weather reports about freezing to

:31:27. > :31:33.the NHS, all in a bid to reduce the 25,000 deaths estimated if there is

:31:33. > :31:38.another big freeze. But it isth still feels as these

:31:38. > :31:42.organisations are often working in the dark. So where are the

:31:42. > :31:47.newspapers getting their headlines from? There seems to be certain

:31:47. > :31:51.forecasters out there claiming they can offer long-term predictions,

:31:51. > :31:55.you can find them on the Internet. Is it really possible to beat the

:31:55. > :32:01.Met Office? For big businesses, being able to plan weeks and months

:32:01. > :32:06.ahead, is invaluable. And our supermarkets are no exception.

:32:06. > :32:15.When bad weather is predicted, we tend to bulk buy, hot chocolate is

:32:15. > :32:19.on the top of our list. And I am, - I'm delighted to say, is bird seed.

:32:19. > :32:23.Supermarkets rely on the road and rail network to keep the shelves

:32:23. > :32:26.well stocked. When bad weather hits, that supply chain comes under

:32:26. > :32:32.threat. These days, most supermarkets have their own in-

:32:32. > :32:39.house weather analysts. That is how important it is to them to know

:32:39. > :32:47.what the weather is doing. I went to find out more from Ross

:32:47. > :32:49.Eggletonn at more sons. This is extraordinary, - more sons, this is

:32:49. > :32:54.extraordinary, are you using the same information as everyone else,

:32:54. > :32:57.are you using the information from the Met Office? We also have an

:32:57. > :33:03.independent provider that provides weather forecasts to us as a

:33:03. > :33:10.business. What do your customers tend to buy? The snow? When it

:33:10. > :33:13.snows behaviour seems - tend to buy in the snow? When the snow comes

:33:13. > :33:19.behaviour shifts, lots of tinned food, in times of harsh weather I

:33:19. > :33:25.think people like comfort, so comfort food seems to be it. Stews,

:33:25. > :33:28.shepherd's pie? It is the home made, more traditional British dishes.

:33:28. > :33:32.By combining Met Office data with information from other sources,

:33:32. > :33:37.this supermarket tries to stay ahead of the game.

:33:37. > :33:41.It is not foolproof, but Ross thinks it lets them get a slightly

:33:41. > :33:47.better handle on what is round the corner.

:33:47. > :33:50.What we have here, this is a map of all of the area serviced by the

:33:51. > :33:56.Bridgwater depot. What we can do is pick up either an individual

:33:56. > :34:00.vehicle, or we can look at a particular area. We get a live feed

:34:00. > :34:04.back from that vehicle that tells us where it is, in temples location,

:34:04. > :34:08.but also how fast it is moving, and - in terms of location, also how

:34:08. > :34:12.fast it is moving, and the distance travelled over the last four or

:34:12. > :34:19.five minutes. Each of the boxes represents a vehicle? Yes when it

:34:19. > :34:22.is snowing we can see where the vehicles are due to the weather or

:34:22. > :34:27.congestion due to weather. Due to this material we were able to keep

:34:27. > :34:30.every store open every day throughout the whole period.

:34:30. > :34:33.Your nightmare scenario would be if you had a huge dump of snow,

:34:33. > :34:40.immediately around where this depot is. Because that then stops

:34:40. > :34:44.everything going out? Absolutely. Our worst case scenario is heavy

:34:44. > :34:48.snowfall on the depot. The risk to our business is not worth

:34:48. > :34:52.contemplating if we can't get out. It is not worth it. The burning

:34:53. > :34:57.question, I suppose, how nervous are you about this winter, what is

:34:57. > :35:00.your forecast telling you? This year we think the pattern might be

:35:01. > :35:03.different. We are expecting heavy snow the last week in November, but

:35:03. > :35:06.particularly in the north-east and Scotland. There is going to be

:35:06. > :35:10.wintry showers in December throughout, we believe. But not to

:35:10. > :35:20.the same magnitude as last year. We believe that the heavy snowfall is

:35:20. > :35:25.probably going to come in the new year. Kind of fascinating, isn't it,

:35:25. > :35:29.that there is a company that is willing to be that prescriptive

:35:29. > :35:32.about what the winter's weather has in store. Not only saying that

:35:32. > :35:37.there is going to be a lot of snow in Scotland and the north-east, at

:35:37. > :35:42.the end of this month, but then prepared to say, snow flurries

:35:42. > :35:46.throughout December, and not until the new year, will there be, a

:35:46. > :35:51.really serious snowfall in the UK. But I'm amazed that they feel that

:35:51. > :35:56.they can give that sort of very, very accurate information. I'm with

:35:56. > :36:00.the Met Office on this, I'm pretty sceptical about being that precise

:36:00. > :36:03.about long range forecasts. The Met Office are not saying it won't snow.

:36:04. > :36:09.What they are saying is we can't predict very accurately on what day

:36:09. > :36:15.it is going to snow. But there are these website, aren't there, that

:36:15. > :36:18.are filling a gap. I suppose we do want and expect very accurate

:36:18. > :36:22.weather forecasts. That's right. People really do want to know this

:36:22. > :36:27.information, because of our national obsession with the weather

:36:27. > :36:34.maybe. I don't think the science is good enough to make those specific

:36:34. > :36:40.predictions. We can actually put our postcode into this one here.

:36:40. > :36:45.That is the postcode for BBC Scotland. What does it say? 13-14

:36:45. > :36:52.degrees in the next few days, the chances of snow are, zero. No real

:36:52. > :36:55.surprise there. But that is five day, you think, that scientifically

:36:55. > :36:59.stands up. Meteorologists around the world would agree with that.

:36:59. > :37:05.That is what weathermen do. What I would be extremely cautious about

:37:05. > :37:10.is saying it will snow in six weeks times or on the 17th of December,

:37:10. > :37:15.or a specific long range forecast. Those specific long range forecasts

:37:15. > :37:20.have got us into trouble in the past. It reminds me of the infamous

:37:20. > :37:24.summer of 2009. The economy may be in the doldrum, at least there is

:37:24. > :37:29.some hope on the horizon for a long hot summer. The Met Office says we

:37:29. > :37:32.are heading for a long period of barbecue weather this year. After

:37:32. > :37:37.the washouts of recent years, it could be a summer to remember.

:37:37. > :37:41.didn't just rain a bit, it poured and poured.

:37:42. > :37:46.I think we better go home, it is getting very, very, very wet.

:37:46. > :37:50.And the weather got even more extreme. Out in the Bristol Channel,

:37:50. > :37:55.cameras spotted what looked like a water spout, while the Isle of

:37:56. > :38:01.Lewis was hit by a tornado. So did the Met Office get it wrong,

:38:01. > :38:07.or were they misinterpreted. I'm going to take you back to the

:38:07. > :38:10.summer of 2009, the infamous summer, where we were promised barbecues

:38:10. > :38:14.from beginning to end. All that happened was it rained, it was

:38:14. > :38:18.pretty cold and our barbecues sat in the garden getting rusty. Why

:38:18. > :38:22.did you get it so wrong? I think the message got translated by

:38:22. > :38:27.certain sections of the press into what is called a deterministic

:38:27. > :38:33.forecast. It will be a hot summer, or something like that. The

:38:33. > :38:37.information we put out was it is odds on for a barbecue summer. The

:38:37. > :38:41.probability was high that we would end up with a warm summer. The

:38:41. > :38:46.summer wasn't as bad as you think, but a bit of a disappointment for a

:38:46. > :38:49.lot of people. This is the problem with any kind of forecast. The

:38:49. > :38:53.weather around us is just too chaotic for anyone to be able to

:38:53. > :38:56.make a definitive prediction more than a few days ahead. And maybe

:38:56. > :39:06.there is another side to this. But the public doesn't always take the

:39:06. > :39:10.weather as seriously as it should. This is the M8 motorway, the

:39:10. > :39:16.busiest in Scotland, brought to a stand still by the worst blizzard

:39:16. > :39:18.to hit the country in 40 years. Hundreds of motorists were left

:39:18. > :39:24.stranded, with no let up in the conditions, many were forced to

:39:24. > :39:31.spend the night in their cars, as temperatures plunged to minus 14

:39:32. > :39:40.degrees send grate. - centigrade.

:39:40. > :39:44.I started at Deerpark at 10.05am. That is me travelling five miles in

:39:44. > :39:48.ten hours. Somebody needs it pay for this. Who? The head of

:39:48. > :39:56.transport. The transport minister. The Met Office warned of severe

:39:56. > :40:00.blizzards and icey roads, a full 12 hours before the snow arrived.

:40:00. > :40:06.new weather feature brings fresh snowfall into the central belt just

:40:06. > :40:14.in time for the rush hour. Despite the warning, motorists headed off

:40:14. > :40:19.to work, and drove straight into a clearly forecast bliz standard. -

:40:19. > :40:22.blizzard. How much warning we get, there is little to keep the roads

:40:22. > :40:26.clear when a blizzard on this scale hits.

:40:26. > :40:30.What about this year? If the last couple of winters are anything to

:40:30. > :40:33.go by, it is a problem not just confined to Scotland. If major

:40:33. > :40:37.roads anywhere in the country aren't treated in time, it is

:40:37. > :40:43.gridlock. Have we learned a valuable lesson?

:40:43. > :40:53.Apparently, we now have 1,500 extra tonnes of grit, stockpiled up and

:40:53. > :40:59.down the country. But is there really enough to go around? It

:40:59. > :41:04.might not look that much, but last year this stuff was like gold dust.

:41:04. > :41:07.UK piles of grit ran dangerously low, some councils ran out all

:41:08. > :41:12.together. There was reports of criminal gangs stealing this stuff

:41:12. > :41:20.and selling it on the black market. The question is, this time round,

:41:20. > :41:23.are we better prepared? I have come to one of three depots

:41:23. > :41:26.that supply Glasgow's fleet of gritters. I'm hoping that Robert

:41:26. > :41:31.Booth, the council's executive director of land and Environmental

:41:31. > :41:35.Services, will convince me this time we will be prepared.

:41:35. > :41:39.I'm pretty sure this is the biggest pile of grit I have ever stood on,

:41:39. > :41:45.how much have you got here? 6,000 tonnes in the barn. 22,000 tonnes

:41:45. > :41:50.held in Glasgow. The simplest question I ask, what is it? That is

:41:50. > :41:55.a mixture of rocksalt, molasses, or sugar. This is salt, with sugar on

:41:55. > :42:01.it? That seems quite a complex thing for grit. Most people think

:42:01. > :42:07.it is dirt. That mixture allows us to melt ice and Snowndown as low as

:42:07. > :42:11.minus 10 degrees. Rocksalt on its own would stop working at

:42:11. > :42:14.temperatures of minus six degrees. It gives us a material better in

:42:14. > :42:17.combatting the severe weather in Scotland and elsewhere. Where do

:42:17. > :42:23.you get it from? Most of our stock comes from Northern Ireland. But we

:42:23. > :42:29.have had to, in the past, purchase from as far away as Chile. This is

:42:29. > :42:35.Irish grit, and that over there a Chilean grit? Most of it, yes.

:42:36. > :42:39.is estimated upwards of 50,000 tonnes per day would be needed to

:42:39. > :42:43.keep Britain moving through another big freeze.

:42:43. > :42:53.It is not just having reserves of grit that is important, you also

:42:53. > :42:55.

:42:55. > :43:02.have to know where and between use Your man is loading up the gritter

:43:02. > :43:06.from the 6,000 tonnes then, when do you know the right time to grit?

:43:06. > :43:11.culmination of factors, we have three weather forecasts every day,

:43:11. > :43:16.one in the morning, noon and 7.00pm at night. We have a number of

:43:16. > :43:21.sensors in the roads across the city. All those factors allow the

:43:21. > :43:25.supervisors to make a decision on between grit. We try to grit before

:43:25. > :43:28.the weather hits the city, get the grit on the road before the snow

:43:28. > :43:32.comes. Temperature sensors in the road can give an indication of

:43:32. > :43:39.where and when the grit is most needed. That level of preparedness

:43:39. > :43:41.isn't cheap. It cost us, last year, �4 million

:43:41. > :43:46.for our winter maintenance programme. That is a lot of money,

:43:46. > :43:50.but a small price to pay to ensure Glasgow continues to operate.

:43:50. > :43:54.This sentiment is echoed across the country, with the vast majority of

:43:54. > :44:01.councils ordering much more grit than in 2010. With luck, that will

:44:01. > :44:06.be enough to avoid the chaos of last year. What's this then, the

:44:06. > :44:08.great British grit-off? It is demonstration time. Clearly. You

:44:08. > :44:13.demonstrate why grit is so important for getting us through

:44:13. > :44:19.the winter. Right, here is a giant bucket of grit, which I may or may

:44:19. > :44:23.not have borrowed off Glasgow council. This is the stuff in the

:44:23. > :44:28.yellow bins you see alongside the road? This one has a lot of rocks

:44:28. > :44:32.in t but basically grit is rocksalt, it is salt. It is a big block of

:44:32. > :44:37.ice. No kidding. You are good, I can see why you're a scientist?

:44:37. > :44:42.know, so what happens is, when you mix salt with water, it reduces the

:44:42. > :44:47.freezing temperature. If I put salt on water it will no longer freeze

:44:47. > :44:51.at zero degrees. Pop some down there. Look it is melting already.

:44:51. > :44:55.Ice has a particular characteristic, it is sort of unique, but it is

:44:55. > :45:00.what makes grit work in terms of gritting the road. I'm going to do

:45:00. > :45:04.something, I will lean my microphone over this? Can you hear

:45:04. > :45:08.it cracking. It is melting. Sorry, go on. When you put your hand on

:45:08. > :45:13.ice, it feels slidey, the reason for that is that ice is not just

:45:13. > :45:18.solid, on the surface it has a constantly changing melting and

:45:18. > :45:23.refreezing cycle, all the time. That is why ice-skaters can glide

:45:23. > :45:28.so easily, there is a thin sheen of water. What happens is, when you

:45:28. > :45:35.add the salt, in the form of grit, to the ice, it he dissolves into

:45:35. > :45:40.that surface layer, and stops it - it dissolves into that surface

:45:40. > :45:44.layer and that refreezes. So you have a surface that is safe for

:45:44. > :45:48.walking? The tyres go over it rather than sliding on the thin

:45:48. > :45:51.surface. There was Koon none drum last year, particularly here -

:45:51. > :45:55.conundrum last year, particularly here in Scotland. It was so cold

:45:55. > :46:02.people were claiming grit no longer worked? That is also true. The

:46:02. > :46:06.reason for, is when you get to minus 7-9 degrees Celsius, the salt

:46:06. > :46:10.doesn't dissolve into the water it freezes too quickly. At that point

:46:11. > :46:14.it stops working. At that point you have to use sand or not go out.

:46:15. > :46:19.all? Probably best. But, but, but, there is another thing, actually is

:46:19. > :46:22.it isn't specific to salt, you can use anything that dissolves in

:46:22. > :46:27.water. It has the effect of reducing the freezing temperature

:46:27. > :46:37.of the water. As we have seen, even sugar can do the job. Last winter

:46:37. > :46:38.

:46:38. > :46:43.there were reports of sheep licking the shrugry grit off the roads.

:46:43. > :46:47.keep your sheep inside if you are using sugary grit! Thank you, great

:46:47. > :46:50.demonstration. How much we love to moan, are our

:46:50. > :46:55.winters really getting worse? Science would argue that in fact we

:46:55. > :46:59.shouldn't be moaning at all. We know, from studying ice core

:46:59. > :47:06.samples, that there was a time when our winters were very different.

:47:06. > :47:09.For a period of almost 300 years, from 1550-1850, the average

:47:09. > :47:13.temperatures in Britain fell by half a degree. Now that doesn't

:47:14. > :47:23.sound a lot, but it had a devastating effect on our climate.

:47:24. > :47:24.

:47:24. > :47:28.This period is known as the little Ice Age.

:47:28. > :47:33.It caused the River Thames to freeze over. Bitter winters reduced

:47:33. > :47:37.the growing season for farmers by as much as two months. Crops failed,

:47:37. > :47:43.forcing up grain prices. The result was malnutrition and familiar

:47:43. > :47:46.anyone, which wiped out huge numbers of the population. - famine,

:47:46. > :47:51.which wiped out huge numbers of the population. Bitter cold winters had

:47:51. > :47:54.become a fact of life. Since then, when you look over the long-term,

:47:54. > :47:57.it looks like our average temperatures have claimed

:47:57. > :48:04.significantly. Despite our last three cold winters, when we look

:48:04. > :48:09.back at snowfall records for the last century. We see that a snowy

:48:09. > :48:19.winter is quite a rare event in the British Isles F it is not the start

:48:19. > :48:21.

:48:21. > :48:27.of a another mini-Ice Age, what is So could three bad winters in a row,

:48:27. > :48:32.simply be a freak of nature, or is there something out there having a

:48:32. > :48:36.profound influence on our weather? The sun, our nearest star, it heats

:48:36. > :48:45.our planet, can it be responsible for freezing Britain? If so, what

:48:45. > :48:49.is it about the sun's activity that cools rather than warms the UK?

:48:49. > :48:52.You would be for given for thinking that the sun might not be the first

:48:52. > :48:55.thing you take into consideration when trying to predict snowfall.

:48:55. > :48:58.But scientists here at the university of Reading have

:48:58. > :49:04.established a clear link between sunspot activity and our winter

:49:04. > :49:10.weather. Sunspots are dark regions on the

:49:10. > :49:15.surface of the sun. They are caused by intense magnetic activity.

:49:15. > :49:20.When they disappear, less heat and light hit the earth. Which the team

:49:20. > :49:25.at Reading believes shows up as a reduction in levels of ultraviolet

:49:25. > :49:33.light. They think fewer sunspots and less UV light means harsher

:49:33. > :49:39.winters. Mike Lockwood is at the forefront of this research.

:49:39. > :49:46.So the sun is nice and warm today, how can the sun actually make our

:49:46. > :49:50.weather colder, it seems very counterintuitive? What it does is

:49:50. > :49:58.it affects the highest part of the at moss stpee, the strat sphere,

:49:58. > :50:02.how the winds propagate down - stratosphere, how the winds

:50:02. > :50:06.propagate down is hard to understand, but we are beginning to

:50:06. > :50:13.do. It is the UV on the sun on the Stratosphere, that determines what

:50:13. > :50:15.happens down on the ground? Europe, yes, it is not a global

:50:15. > :50:18.problem. It is something that affects Europe, and Eastern Europe

:50:18. > :50:22.and here, we are on the edges in the UK. Mike and his colleagues are

:50:22. > :50:27.using data from satellites that measure ultraviolet light from the

:50:27. > :50:34.sun. They have detected a reduction in

:50:34. > :50:38.UV levels, and think this is a result of the solar cycle.

:50:38. > :50:43.The most well known cycle of the sun is roughly 11 years, it goes

:50:43. > :50:49.from being very quiet to very active and back again, and on an 1-

:50:49. > :50:55.year cycle. What is the sun doing right now - 11-year cycle. What is

:50:55. > :51:01.the sun doing right now, what part of the cycle is it at? We have

:51:01. > :51:05.emerged from the longest solar minimum we have had since the 1920.

:51:05. > :51:09.Right now they think we have fewer sunspots and less UV light hitting

:51:09. > :51:14.the earth. In turn, they are modelling how these changes affect

:51:14. > :51:17.the earth's statistics to fear, which could change the weather -

:51:17. > :51:22.stratosphere, which could change the weather systems we experience

:51:22. > :51:28.on the ground. What we found is when solar activity is unusually

:51:28. > :51:32.low. As it has been recently. jetstream can find these big

:51:32. > :51:38.meanders, and that can influence the weather underneath, and in

:51:38. > :51:44.winter, particularly, it affects us here. Ultimate irony, in a warming

:51:44. > :51:47.world, Europe may get more cold winters. They think it is the

:51:47. > :51:50.Northern Hemisphere that is vulnerable, and low solar

:51:50. > :51:57.activities could be one of the factors that causes the jetstream

:51:57. > :52:00.to behave unusually. Remember blocking, that big bad weather wolf,

:52:00. > :52:05.Mike's colleague, Dr Tim Woolings is working on what causes it and

:52:05. > :52:08.how quickly it can happen. blocking event is basically a type

:52:08. > :52:14.of weather pattern, that is fairly persistent. We will have the

:52:14. > :52:18.weather pattern sticking around for a whole week or two. So here we go,

:52:18. > :52:23.this is the blocking forming with the air being pulled up from the

:52:23. > :52:28.Tropics over Greenland. This dense, dark blue bit here is cold air from

:52:28. > :52:32.the Arctic? Exactly. That is being pulled down. That's right. These

:52:32. > :52:36.events are pretty persist dent for weather patterns. Once it has

:52:36. > :52:41.actually started, then, yes, we have quite a bit of predictability

:52:41. > :52:46.for the next week or so. The key is when they will start. It does look

:52:46. > :52:50.very, I'm not jealous of you trying to solve these problems, it looks

:52:50. > :52:56.insanely chaotic to me. It looks like you can't actually predict?

:52:56. > :52:59.This is it, it is maizeing weather prediction works at all - as

:52:59. > :53:03.amazing weather prediction works at all. The idea is still the subject

:53:03. > :53:11.of much discussion, tantalising though it is, it is likely to be a

:53:11. > :53:15.few years yet before this theory is fully understood. Predicting the

:53:15. > :53:20.weather is fiendishly difficult, because there are so many complex

:53:20. > :53:23.and chaotic factors involved. When scientists look at the bigger

:53:23. > :53:28.picture, including solar activity, they can get a much more detailed

:53:28. > :53:37.understanding of how local weather works. Ultimately, that means

:53:37. > :53:41.better, more accurate snow forecasting.

:53:41. > :53:45.Now I know that there are very few of you sitting at home watching

:53:45. > :53:49.this thinking please let's have another long, hard, cold winter,

:53:49. > :53:53.but you can't deny it, there is something very romantic about a

:53:53. > :54:01.white Christmas, isn't there? Everybody loves a white Christmas.

:54:01. > :54:06.I think Bing Crosby is largely responsible for that. And Charles

:54:06. > :54:11.Dickens. The last official white Christmas was in 2009. The official

:54:11. > :54:16.criteria for a white Christmas is that a single snowflake has to fall,

:54:16. > :54:21.it doesn't have to land. That cannot be true. Surely your perfect

:54:21. > :54:26.white Christmas is piles of mince pies and snow everywhere, singing

:54:26. > :54:32.Robins? Alas, no, it gets mori dick Louis. There are nine specific

:54:32. > :54:37.locations where a white Christmas can be officially designated.

:54:37. > :54:45.Aberdeen Football Club. Just get this right, if one snowflake falls

:54:45. > :54:51.above Aberdeen Football Club it is a white Christmas. Belfast Airport,

:54:51. > :54:55.Birmingham Bull Ring, a shopping centre. Cardiff, Millenium Stadium.

:54:55. > :55:00.Edinburgh Castle, Glasgow Cathedral, Liverpool, the Albert Dock,

:55:00. > :55:07.Buckingham Palace. If the Queen sees one. Manchester it is Granada

:55:07. > :55:11.Studio, and the next one is my back garden. I made that one up! So, if

:55:11. > :55:15.a snowflake is observed in the sky, it doesn't have to fall, it doesn't

:55:15. > :55:20.have to settle over any of those locations it is a white Christmas?

:55:20. > :55:25.It is officially a white Christmas. That is a rubbish white Christmas?

:55:25. > :55:30.In London it is currently 10-1. That it will be a white Christmas?

:55:30. > :55:34.Glasgow it is 7-1. There is a bet which I'm not going to make.

:55:34. > :55:39.you not? It is ludicrous. So you are saying what, do you think it is

:55:39. > :55:43.going to snow, do you think it will be a white Christmas? No. It is

:55:43. > :55:47.definitely not. Look, he's a scientist and hedging his bets.

:55:47. > :55:52.Scientists don't make bets. If I knew it was going to snow then I

:55:52. > :55:56.would make a bet. That is what science does. It is pathetic, let's

:55:56. > :56:00.remind ourselves of what our experts have told us. It is going

:56:00. > :56:04.to snow somewhere in the British Isles this winter. Anyone who turns

:56:04. > :56:08.around and says on the 25th of December it will snow is, quite

:56:08. > :56:12.frankly, a fool. We are expecting some heavy snow the last week in

:56:13. > :56:17.November, particularly in the north-east and Scotland. Will it

:56:17. > :56:21.snow this winter? You will have to talk to the Met Office about that

:56:21. > :56:25.and see their latest predictions. Being able to pinpoint the precise

:56:26. > :56:30.conditions under which snowfalls in the atmosphere, could offer help to

:56:30. > :56:34.forecasters when it comes to predicting a monster snowfall hit.

:56:34. > :56:40.At the moment, long-term predictions can only give us an

:56:40. > :56:44.idea of the type of conditions to expect in a winter. They can't tell

:56:44. > :56:47.us categorically if and when it will snow. The good news is

:56:47. > :56:50.meteorologists can recognise the kind of weather system that brings

:56:50. > :56:57.very cold conditions, one that blocks the warming effects of

:56:57. > :57:04.currents like the jetstream and the thermohaline circulation that keep

:57:04. > :57:11.the UK mild. It is a system that can close in on us in a matter of

:57:11. > :57:14.days t can't be picked bup I long range forecast. For the mini-Ice

:57:14. > :57:19.Age,s expert consensus is there is no compelling evidence. Some argue

:57:19. > :57:25.we may even be in for a run of milder winters. We may not know

:57:25. > :57:28.where or win it will snow, but we do know that it will snow. The

:57:28. > :57:31.heartening thing we have discovered on the epic weather quest around

:57:31. > :57:34.the country, is people are beginning to take the idea of

:57:35. > :57:39.winter much more seriously. Organisations like our supermarkets

:57:39. > :57:43.and the health service and airports, are getting prepared for the worst.

:57:43. > :57:46.So that if it does happen, we shouldn't get into the pickle that

:57:47. > :57:51.we did last winter. That's right, it is the beginning of November

:57:51. > :57:54.right now, all the best data we can get from the Met Office suggests we

:57:54. > :57:57.are not going to have a particularly cold winter. But, what

:57:57. > :58:00.we have learned is that the position of the UK on the earth,

:58:00. > :58:04.means that our weather systems are chaotic and difficult to predict.

:58:04. > :58:09.So we can't rule out the possibility that we may get a

:58:09. > :58:13.sudden big freeze. Don't shout at the weatherman if it happens. And

:58:13. > :58:17.also, remember that we are, standing here, at the beginning of

:58:17. > :58:21.November, that is the beginning of winter, a season where temperatures

:58:21. > :58:25.drop, and occasional bad weather does get flung at our doorsteps.

:58:25. > :58:29.Here is my little piece of advice, for what it is worth. Dig out the

:58:29. > :58:37.winter woolies, stock up on hot chocolate and bird feed and get out