:00:10. > :00:18.This is Antarctica, the last great wilderness.
:00:19. > :00:24.It's the coldest, windiest, driest and most isolated place
:00:25. > :00:29.on Earth, and it's home to the British Antarctic Survey's
:00:30. > :00:36.Here, cutting-edge science is making vital discoveries
:00:37. > :00:41.about how our lives are vulnerable to the sun's activities
:00:42. > :00:47.and threatened by man-made climate change.
:00:48. > :00:52.It's 27th of January, 2016, and we're at 75 degrees south.
:00:53. > :00:55.For the last couple of weeks, we've been on this ship behind me,
:00:56. > :01:01.the RRS Ernest Shackleton, crossing the Southern Ocean.
:01:02. > :01:04.We're making this journey to resupply the research station,
:01:05. > :01:11.but this is also something of a rescue mission.
:01:12. > :01:15.Although it appears to be on solid ground, Halley actually sits
:01:16. > :01:20.on a constantly-moving and cracking ice shelf - an ice shelf that's
:01:21. > :01:25.developed a chasm that threatens to cast the station adrift
:01:26. > :01:28.on a massive iceberg - and our cargo is part of the effort
:01:29. > :01:39.I'm Peter Gibbs, and my job is working for the Met Office
:01:40. > :01:42.as a BBC weatherman, but back in my younger days I worked
:01:43. > :01:45.as a meteorologist in Antarctica for over two years, and I never,
:01:46. > :01:51.ever thought I'd get the opportunity to return.
:01:52. > :01:54.'This is my journey to investigate the threat to Halley's
:01:55. > :01:56.future...' OK, Hilmar, here we go, then.
:01:57. > :02:01.It's going over the edge that's the worst bit.
:02:02. > :02:03.'..and science at the end of the world.'
:02:04. > :02:24.My journey starts at the southern tip of Africa.
:02:25. > :02:31.Here, the Royal Research Ship Ernest Shackleton is waiting for me.
:02:32. > :02:34.As I go below to find my cabin and stow my bags...
:02:35. > :02:46.We're heading out of Cape Town harbour -
:02:47. > :02:51.you can probably see Table Mountain in the background behind me -
:02:52. > :02:55.on our way to the frozen continent of Antarctica.
:02:56. > :02:58.Now, we're expecting it to take about two weeks.
:02:59. > :03:02.We'll be going at ten to 12 knots, so at just
:03:03. > :03:07.We're also heading through some of the roughest seas in the world,
:03:08. > :03:10.so I'm a little bit nervous about that, but really,
:03:11. > :03:47.really excited to be heading for Antarctica.
:03:48. > :03:49.The Ernest Shackleton has been making this long journey
:03:50. > :03:51.across the Southern Ocean to resupply Halley since 1999,
:03:52. > :03:53.but British scientific research goes back much further and has
:03:54. > :03:57.The modern-day British Antarctic Survey actually has its roots
:03:58. > :04:00.in a secret wartime mission from World War II, which was based
:04:01. > :04:01.up here on the peninsula at Port Lockroy
:04:02. > :04:05.The idea of the operation was to protect the waters around
:04:06. > :04:07.Antarctica, particularly towards the Drake Passage
:04:08. > :04:23.towards South America, from Nazi submarines.
:04:24. > :04:25.After the war, territorial claims led to 12 nations signing
:04:26. > :04:27.the Antarctic Treaty, and this untouched landscape
:04:28. > :04:29.became a home purely for scientific exploration.
:04:30. > :04:31.For the British Antarctic Survey, this meant a research station
:04:32. > :04:38.And that's our destination - Halley Research Station.
:04:39. > :04:43.Even the buildings I lived in have long since drifted off,
:04:44. > :04:49.We've still got a long way to go - the best part of a week.
:04:50. > :05:07.In fact, we are not even on the edge of this map yet.
:05:08. > :05:13.Various incarnations of the Halley Research Station have
:05:14. > :05:15.endured some of the most hostile conditions found
:05:16. > :05:26.Temperatures drop to over minus 50 Celsius, winds can reach almost
:05:27. > :05:36.150km an hour, reducing visibility to just a few metres...
:05:37. > :05:50...and, for over three months every winter, the sun never rises.
:05:51. > :06:01.Antarctica is also about as remote a place as you can find on Earth...
:06:02. > :06:04...but it's this remoteness that allows experiments to be performed
:06:05. > :06:32.at Halley that simply can't be done anywhere else.
:06:33. > :06:36.through the Southern Ocean to get to Halley is a challenge.
:06:37. > :06:39.Well, we finally hit the edge of the Weddell Sea pack ice
:06:40. > :06:44.There was an almighty bang as we struck the first floe,
:06:45. > :06:47.The sound when you're actually inside the ship is just remarkable.
:06:48. > :06:50.It's almost like you're inside a war zone, and this
:06:51. > :06:59.I'll tell you what, it's still a bit nerve-racking until you
:07:00. > :07:07.As we crunch through the ice, the captain offers me
:07:08. > :07:10.the chance of a lifetime - something I'd secretly been hoping
:07:11. > :07:16.to do - drive his 1,800-tonne ship.
:07:17. > :07:18.Are you sure about this, John?
:07:19. > :07:25.At the moment we've got 83% pitch, which is basically your power,
:07:26. > :07:28.which is giving us about ten knots, but it will build up,
:07:29. > :07:33.cos we're in a patch of open water here.
:07:34. > :07:35.So, just be careful what you hit at that
:07:36. > :07:41.It's a strange sort of feeling of power and terror, actually.
:07:42. > :07:48.nice new ice coming up, here, and just aim for the crack
:07:49. > :07:58.That's incredible - the speed that crack's actually formed,
:07:59. > :08:01.There's a good covering of snow on most of these
:08:02. > :08:08.It's probably the best part of a metre thick, with
:08:09. > :08:13.It's certainly slowed us down a bit. Yes.
:08:14. > :08:16.And are we OK to hit this bit of ice coming up?
:08:17. > :08:19.You might want to just drop your pitch...
:08:20. > :08:32.Drop your power a bit there.
:08:33. > :08:34.My piloting skills have the local penguins fleeing
:08:35. > :08:36.in terror but I'm not stopping for anything.
:08:37. > :08:38.I have to say, this is fantastic fun.
:08:39. > :08:40.I can see why you keep coming back down here, John.
:08:41. > :08:44.We spend our whole careers at sea, trying to avoid
:08:45. > :08:52...and this is our one chance to hit everything in sight.
:08:53. > :09:05.is an unforgettable experience, like exploring another
:09:06. > :09:11.universe in a spaceship, but we're still a world away
:09:12. > :09:19.Even through the Halley Research Station appears
:09:20. > :09:23.to be built on solid ground, it isn't.
:09:24. > :09:30.Its home is the Brunt Ice Shelf - a seemingly endless frozen sea -
:09:31. > :09:45.and, for the research station, this is a problem.
:09:46. > :09:47.The ice shelves that surround Antarctica are glaciers
:09:48. > :09:52.that have flowed down from the continent's landmass.
:09:53. > :09:55.Hundreds of metres thick, they crack as they spread like a stiff honey
:09:56. > :10:15.So, ice shelves grow with time, as more and more ice is being added,
:10:16. > :10:18.and typically they then lose mass through an event that they call
:10:19. > :10:21.calving, which is basically the breaking off of a chunk
:10:22. > :10:24.of the ice shelf, which breaks away and then floats
:10:25. > :10:29.This is a natural process, which you always expect.
:10:30. > :10:35.It happens with other ice shelves as well and certainly will happen
:10:36. > :10:40.On Brunt Ice Shelf, we have a particular
:10:41. > :10:42.situation right now, which is that there's
:10:43. > :10:49.It was formed at least 30 years ago, but recently it has
:10:50. > :10:55.Now, if this crack were to continue to grow at the same rate as it has
:10:56. > :10:59.over the last few years, in the same direction,
:11:00. > :11:01.then eventually it will cut across the whole ice shelf.
:11:02. > :11:07.We know there was a huge calving event between 1915 and 1956,
:11:08. > :11:13.when the coastline of the ice shelf dramatically changed,
:11:14. > :11:16.and now the ice shelf has almost extended to its 1915 profile,
:11:17. > :11:22.so another major calving event is due.
:11:23. > :11:26.If that happens, then the research station itself will be cast adrift
:11:27. > :11:44.into the Southern Ocean on a huge tabular iceberg.
:11:45. > :11:52.That glistening white line in the distance are the icy ramparts
:11:53. > :11:56.of the Caird Coast - the continent of Antarctica.
:11:57. > :11:58.A coast first spotted and named by Shackleton
:11:59. > :12:00.just over 100 years ago, before he got trapped in the ice
:12:01. > :12:07.just further down the coast here, and first spotted by me 36 years ago
:12:08. > :12:13.There's a bit of that young man certainly coming back as I stand
:12:14. > :12:31.My first sight of the ice shelf brings back a flood of memories.
:12:32. > :12:34.It's a bleak, beautiful place - an alien world, right
:12:35. > :12:49.And it's a treacherous landscape - at any moment, at the water's edge,
:12:50. > :13:10.'But we have a job to do, delivering supplies
:13:11. > :13:12.'for the research station.' And, with no docks, like everything else
:13:13. > :13:14.in Antarctica, you make what you need yourself.
:13:15. > :13:17.So, Captain Harper creates a berth by running the ship
:13:18. > :13:24.If the shelf doesn't collapse, so the theory goes,
:13:25. > :13:27.Violent southern ocean storms could drive the Shackleton
:13:28. > :13:30.off the ice shelf, so, as the weather closes in,
:13:31. > :13:34.the rest of our day is spent securing the ship.
:13:35. > :13:38.This means all hands, including me, go to work digging four massive
:13:39. > :14:15.The 30km snowcat ride across the blindingly white ice
:14:16. > :14:22.shelf seems endless but, after two weeks at sea
:14:23. > :14:29.waiting for this moment, I'm not disappointed.
:14:30. > :14:35.I mean, I've seen pictures, but when you see it for real it's
:14:36. > :14:38.I mean, it's like something out of The Martian or
:14:39. > :14:59.Built in 2012, the Halley Research Station consists of 'eight huge
:15:00. > :15:00.to maintain life in a hostile environment.
:15:01. > :15:04.to take you through from one end, right through to the other.
:15:05. > :15:13.So, we're starting in the quiet room, which doubles up as a library,
:15:14. > :15:15.and we move out of there into the first part
:15:16. > :15:18.Now, we're into a sort of admin area.
:15:19. > :15:21.We've got the communications room on the left.
:15:22. > :15:26.We've got the equipment here, on the right, in case of fire,
:15:27. > :15:30.and a board up here where you have to tag in and tag out -
:15:31. > :15:32.safety, a very big concern here at the moment.
:15:33. > :15:36.Now, we're moving through into the main dining
:15:37. > :15:42.So, this is the real, sort of, hub of the station far
:15:43. > :15:48.Oh, and along the wall on this corridor that
:15:49. > :15:50.we're just coming past, all the pictures of past winterers,
:15:51. > :15:59.starting from 1956, right through to the present day.
:16:00. > :16:03.And, of course, there's me and the rest of the guys in 1981,
:16:04. > :16:06.and you'll notice, back then, no women.
:16:07. > :16:14.Now, you'll start to hear a bit of a hum.
:16:15. > :16:19.We're going outside, through these heavy,
:16:20. > :16:36.And now we're on into the main science area,
:16:37. > :16:45.and now we're going to go up the stairs to the best view
:16:46. > :16:48.in Halley, which is the Met Office observation deck, where you get
:16:49. > :17:12.a panoramic view of the Brunt Ice Shelf.
:17:13. > :17:15.But, today, the very existence of this unique research
:17:16. > :17:18.A huge crack across the Brunt Ice Shelf is expanding,
:17:19. > :17:20.and it may cause the research station to float off
:17:21. > :17:26.For glaciologist Hilmar Gudmundsson, it's like watching geology in fast
:17:27. > :17:33.forward, so this faultline is constantly monitored,
:17:34. > :17:39.and there really is only one way to get a closer look.
:17:40. > :17:42.The last time I abseiled was 35 years ago, so I'm a
:17:43. > :17:49.It's going over the edge that's the worst bit for me.
:17:50. > :17:54.It's quite a long way down, isn't it?
:17:55. > :17:57.I've been looking at this crack from satellite images, and now
:17:58. > :18:02.This is a feature which has been here for ages.
:18:03. > :18:08.When low cloud and snow reflect and diffuse the sunlight,
:18:09. > :18:11.the full extent of the chasm is difficult to see,
:18:12. > :18:23.but when the sun comes out, it's a different story.
:18:24. > :18:25.This is, as you can see, a fairly large crack.
:18:26. > :18:27.It's a chasm, that's what they call it.
:18:28. > :18:31.Yeah, chasm, chasm sounds about right from where I'm sitting.
:18:32. > :18:34.Across, I would say this is maybe 80...80m at least...
:18:35. > :18:39...and the whole thing is getting wider as we speak,
:18:40. > :18:44.Every day? Every day.
:18:45. > :18:48.15cm from this edge here to the other one over there,
:18:49. > :18:53.and it's been going like a clock ever since we started
:18:54. > :18:59.And, Hilmar, the bottom of the chasm, there,
:19:00. > :19:02.looks very different to the ice round about.
:19:03. > :19:05.It's much darker down in the bottom, there.
:19:06. > :19:11.Yeah, I suspect down there we're literally at sea level.
:19:12. > :19:15.It is the colour of the ocean which is causing this slight tint.
:19:16. > :19:19.Hilmar is keen to investigate whether we are actually at sea
:19:20. > :19:25.level, and that means going right to the very bottom of the chasm.
:19:26. > :19:32.It's a huge relief getting down, but we don't take off
:19:33. > :19:37.With the freezing Southern Ocean just beneath our feet,
:19:38. > :19:43.Matt, are you happy with us going down here?
:19:44. > :19:45.If you follow the trail we've made previously,
:19:46. > :19:54.OK. Are you OK?
:19:55. > :20:05.OK, I'll follow - maybe not quite as elegantly as you did.
:20:06. > :20:21.It really is? Oh.
:20:22. > :20:26.Yeah, yeah, I thought we had, maybe, one or two metres
:20:27. > :20:31.So we're on this huge, floating mass of ice,
:20:32. > :20:34.We've had a journey up from the coast of three
:20:35. > :20:41.We've come an hour and a half in from the base, across this
:20:42. > :20:45.featureless snow plain, to this massive, great chasm,
:20:46. > :20:49.and you get down to the bottom of it and you actually
:20:50. > :20:53.It feels like you're in the belly of the ice shelf,
:20:54. > :20:56.and it just brings it home how sort of precarious this whole
:20:57. > :20:59.I guess, because it's always breaking up, it's growing,
:21:00. > :21:04.it's widening by about 15cm a day, the sea ice formation just
:21:05. > :21:09.This rapid expansion of the chasm may prevent sea ice from forming,
:21:10. > :21:12.but it's not the width that's the threat to
:21:13. > :21:18.the Halley Research Station - it's the length.
:21:19. > :21:21.At the same time that this gets wider, it also gets longer
:21:22. > :21:31.So, if it kept on going at that rate, in that direction,
:21:32. > :21:35.eventually it's going to reach the sea at the other side of the ice
:21:36. > :21:37.shelf, and you've got a massive iceberg.
:21:38. > :21:40.And, of course, the problem here is, Halley, the station,
:21:41. > :21:41.is on that developing iceberg.
:21:42. > :21:57.As it lengthens, the greater the chance that the research station
:21:58. > :21:59.finds itself floating into the Southern Ocean.
:22:00. > :22:01.But there's another unusual feature in Halley's design,
:22:02. > :22:04.the first of its kind, which will help it survive.
:22:05. > :22:09.At the bottom of its hydraulic legs are huge skis...
:22:10. > :22:14...so each module will be detached from its neighbour then dragged
:22:15. > :22:20.to a new site in the same way it was brought here four years ago.
:22:21. > :22:23.After extensive surveys, a new location has been found 20km
:22:24. > :22:34.away, safely on the other side of the chasm.
:22:35. > :22:46.And there, Halley can continue its work.
:22:47. > :22:49.Before we head home, at the edge of the ice shelf,
:22:50. > :22:51.all the ship's cargo is finally unloaded.
:22:52. > :22:53.These big, red shipping containers we brought down on the Shackleton
:22:54. > :22:55.contain living accommodation - kitchen, bedrooms,
:22:56. > :22:58.bathrooms, working spaces - and they are going to be used
:22:59. > :23:01.to build a temporary camp for the team up at Halley VI.
:23:02. > :23:04.So it's all hands on deck at the moment, the container
:23:05. > :23:08.is being craned out over the ice onto these heavy-duty sledges that
:23:09. > :23:16.will then be dragged all the way up to Halley VI.
:23:17. > :23:20.Once the temporary accommodation is set up, then Halley can be
:23:21. > :24:02.It is a little bit warmer for us across the UK than it was for Pete,
:24:03. > :24:08.but it is still not pleasant across the UK. A lot of cloud around and
:24:09. > :24:09.outbreaks of rain for many. Hints of sunshine