this is bbc world news, the headlines. a u—turn by the british government — as it confirms all primary schools in london are to remain closed for the start of term. the city's mayor said the government had ‘finally seen sense‘ research confirms the new coronavirus variant discovered in the uk has a much quicker rate of transmission — the variant has now been identified in at least 18 countries around the world. a new era begins, as the brexit transition period ends and the uk completes its formal separation from the european union. # last christmas, i gave you my heart, # but the very next day, you gave it away and 36 years after its first release, wham!‘s ‘last christmas‘ finally tops the uk music charts.

now on bbc news. antarctica is one of the most remote and inhospitable places on earth. in this edition of our world justin rowlatt joins an international team of scientists travelling to thwaites, the so—called doomsday glacier. antarctica — the world‘s most remote and inhospitable continent. this is the story of a team of scientists who are trying to get to thwaites, the so—called ‘doomsday glacier‘. no—one‘s has really been under thwaites, and what icefin‘s going to do is get up and close to the sea floor and allow us to see what is happening in a real way. oh, oh! look at that! 0h! yeah! what happens to thwaites affects us all because as it melts it will drive up the sea level around the world.

this glacier is part of a system. if it all of that goes, you could end up with upwards of three metres of sea level rise. but first, the scientists need to get there. it‘s so difficult to operate here! all of the planes are grounded. they say we won‘t fly anywhere. one only does anything in antarctica with the cooperation of the weather. antarctica is a place of extremes. it is the coldest, highest, driest and windiest continent on earth. capped by an ice sheet of up to five kilometres thick, this continent contains 90% of the world‘s ice. i begin myjourney

in new zealand. i don‘t need your passport, that‘s all good. they say travelling to antarctica is like travelling to another planet. so, here goes. the us air force provides the planes. the safety briefing may be familiar, but nothing else about this flight is. i‘m travelling with professor david vaughan, the director of science at the british antarctic survey. after flying due south for five hours, i get my first glimpse of antarctica, snow and ice stretching as far as the eye can see. finally, our destination. we are heading to mcmurdo.

which is pretty much straight off over there. it is the last fingerhold of civilisation, the most southerly town on earth, and the largest centre for scientific research on the continent. and out across the sea ice, the first peaks of the mighty tra nsa ntarctic mountains. keep it staying in place... it is here in mcmurdo that our expedition to the thwaites glacier begins. so, thwaites glacier is vulnerable and there is nothing stopping a collapse once it really takes hold. thwaites glacier is the size of britain and already accounts for 4% of global sea level rise. the fear is if the melt rate increases, much of the west antarctic ice sheet could go, too. that could raise world sea levels by more than three metres.

why is the glacier changing, why is it being eaten away? it‘s being eaten away because there are winds on the ocean‘s surface that are actually driving currents away from this ice sheet. when that happens, this water comes in underneath like this. this deep ocean water is really warm. and that eats away at the glacier? this normally doesn‘t happen. these winds have been increasing and so more of this water has been coming up onto the continental shelf and interacting with this glacier. the scientists say global warming has changed the wind patterns and sea currents, bringing warm ocean water to the front of the glacier. we have loaded the atmosphere with carbon dioxide, we have set the temperature going up, and... doctor britney schmidt is in charge of a nasa robot submarine called icefin. the plan is to lower it almost

half a mile through the ice to map conditions in the seawater below. so, britney, give me a tour of icefin? so, up at the front we have sensors that are going to make measurements of the oceanography, telling us what the temperature is, and the salinity of the water and how much oxygen is there. in addition to that we have a forward—looking sonar here that allows us to map the three—dimensional cavities, so it allows us to see the shape of the ice and its texture. no—one‘s really been under thwaites, and what icefin‘s going to do is get up and close to the physics, get really close to the ice, really close to the sea floor and allows to see what is happening in a real way. how much of a challenge do you think this is going to be? well, it‘s always an impressive challenge to do anything here in antarctica and much more so when you are — you know — 1,200 miles from mcmurdo. when you think about drilling through 600 metres of ice, drilled by the best people in the world just to make an observation, it‘s quite a challenge.

and then to operate a moving platform through is pretty special, actually. icefin may have a big task ahead, but not the one as big that faced the men who stayed in this part. so this is a truly unique historical site literally frozen in time. it is the base camp of captain scott‘s ill—fated 191! attempt to reach the south pole. whispering: look at this! this is amazing. that‘s incredible. i‘ll tell you what strikes you first. it‘s — it‘s the smell, it really smells of... ..kind of smoked fish. so there are all sorts of objects. the tin cans and the food they ate on the expedition. so we‘ve got, tinned salmon? that looks like a can of sardines. here we have cocoa,

a huge drink for them, that was the drink of the polar explorers, they make cocoa. and dry, hard biscuits — ship‘s biscuits, baking powder. this is seal blubber. what they would do is kill the seals on the ice, bring them back here, eat the meat and use the blubber to burn their stoves to keep them warm. which is why it smells like smoked fish in here, because it is covered, you can see it is just covered with soot from the blubberfire. it‘s actually really ghostly because you get a sense of the people being here. scott himself leaving from here with that great ambition to get to the pole and then of course dying on the way back. and like captain scott before us, our plans are frustrated by the antarctic weather. i am beginning to understand why doing science here is so difficult.

then i hear a crisis meeting has been called. the delays have got so bad they‘re going to have to scale back some of the science. i want to find out what‘s going on. i managed to track down david vaughan. well, i think there‘s a lot of ambitions at stake here. people have been working on these projects for several years already. so, when the bad news comes, i don‘t think it is quite yet but, the delays are continuing. things are going to change and that is going to mean a lot for some people. can i come to the meeting? i would rather you did not on this one, justin. i‘m not allowed in? no. so you‘re not expecting — a difficult meeting, but? no, no, i think — but we just to people — let people get that news and process it and think about what they‘re going they‘re actually going to when they actually get — finally get in the field. thank you very much. good luck. thank you. when the meeting‘s over,

i learned the weather is hampering efforts to supply spare parts to the plane we need to get to thwaites glacier. there‘s parts coming down from new zealand to get those plans functional again. so we have to sit and wait. how many days behind schedule are we now? uh, i don't really even — i don't know, actually. why count? i think we can still imagine that we can still do 100% of the tasks but... you can still imagine? i can still imagine that we could do — with the following wind — 100% of the tasks but time is getting very, very tight. people are getting a little itchy and a little bit concerned. one only does anything in antarctica with the cooperation of the weather. suddenly the weather clears and miraculously it seems the project is back on track.

it‘s all hands on deck to get the kit boxed up and transported to the airfield, ready to go. and the team are there, itching to get cracking. so we are super excited. we‘re out at lilyfield and we‘re finally about to get to the plane out to thwaites divide. i can‘t wait to get out and start the next phase of the melt project. you can‘t fly straight to thwaites, there‘s no ice runway that can take these big planes. so the 1,300 milejourney is done in stages. thwaites divide is the project‘s staging post in the middle of the west antarctic ice sheet. this is where passengers fuel and cargo are dropped off before being ferried on to the field sites on the glacier itself. the plan is only to stay here for a couple of days, but this being antarctica, it‘s not long before

the weather changes again. so we‘ve been out here for like, i don‘t know, an hour and a half, and this is the result. it gives you an idea of why it is so difficult to operate here. all the planes are grounded, they‘re saying we won‘t fly anywhere for at least three days. keeping the camp from being overwhelmed by snow is a full—timejob for the snowploughs. the wind is gusting up to 50 miles an hour and the temperature is —20. check the snotcicles on this! oh, my god, that‘s absolutely horrible. oh, god. ergh. i can‘t get it off. i do manage to warm up but i realise something isn‘t quite right. my finger has gone all kind of white and it looks a bit burnt. i think you should go and see the doctor to see if it needs a dressing on it because it

doesn‘t look right to me. david is worried it could be the early stages of frostbite, commonly known as frostnip. can you feel that? i can feel it but it doesn‘t feel the same as... it doesn‘t feel the same as the other fingers. it feels a bit numb. frostnip is a freezing of the tissue but not a permanent freezing of the tissue. no ice crystals in the deep tissue like you would with full frostbite. so i haven‘t actually killed the top of my thumb just yet? not just yet. for the next couple of days, it‘s going to be more likely to get frostbite. the cold and the wind and the vast distances here make the logistics of a project like this very challenging. two ice—hardened ships brought hundreds of tons of fuel and cargo to a remote ice shelf. then, specialists snow vehicles hauled it a 1000 miles over land. everything was previously done by aircraft and then as science projects grew, and equipment grew, there became a need to do it more efficiently and cost effectively. each machine will

pull up to 70 tons. these vehicles have transformed the science we can do in antarctica, increasing the scale, the number of people, the number of scientists we can bring to bear on these problems. six people can deliver all the cargo for maybe 30 scientists, and then we can deliver the fuel that can operate five or six airplanes. wejust truck along, day from day, nobody really knows where we are and then we just suddenly turn up. delivering bounty — bladders of fuel instead of sacks of presents. presents would be very welcome because even in these extreme conditions, there are some traditions that have to be kept up. what are you doing? i‘m preparing us for christmas at the south pole. and christmas is not christmas without a few carols. they tried to get us to sing but we didn‘t practice. we don‘t have a song so we told somebody else.

who are we competing against? lower thwaites. how many people at lower thwaites? less than here. how many? five people. # jingle bells, jingle bells, jingle all the way. # oh what fun it is to ride on one—horse open sleigh. cheering and it doesn‘t stop there, i knew i was spending christmas on the ice and was all set to have to forgo my turkey dinner — how wrong i was. and i made some salmon, turkey, ham. that is quite a christmas spread. 0reo cheesecake. it looks amazing, hey. all in western antarctica. all in the middle of nowhere.

christmas is over and the storm has blown itself out. time to load up for the final 400 miles to the glacier. not in one of the big planes this time, in something much smaller. this is a twin 0tter — rugged, reliable and great on short runways, perfect for working out here on the ice. we‘re headed to the place where the base of the glacier goes afloat. it‘s called the grounding line, and it‘s where this glacier is melting. an advance party are already on thwaites glacier. theirjob — to map the area where the scientists are going to be deployed to make sure it‘s safe. the glacier is littered with deep crevasses, which could be lethal. this is actually the first open crevasse we‘ve driven into. you can see the layers here don‘t connect with these layers over here. this is a void, the actual crevasse itself, which is the one right here.

another team survey the site to pinpoint exactly where the grounding line is. it‘s taken almost five weeks but we are finally at the front of the glacier. until this year, only four people had ever been here before. oh my god! hello friend. this is where icefin is going to be deployed but first, they need to drill a hole, or rather melt one, using hot water to bore down almost half a mile into the ice. so task one — create a vast reservoir of water using this huge rubber bath which the scientists call a flubber. we need ten tons of water again. 10,000 litres of water? when we want to do the drilling, we‘ll pump that water using these large borehole pumps and those heaters over there.

they‘re essentially boilers. they‘re like an oversized domestic boiler. heat the water, get it hot enough to melt the ice, put it down the hole. it‘s taken us what, five, six weeks to get here. huge amounts of resources have gone into bringing the fuel and all the stuff you need. how does it feel to be, kind of, the top of the... the cutting bit. there‘s a serious sense of responsibility. there‘s a huge amount of money, time and effort gone into this by a lot of people to get us here. so many things can go wrong and if you lose the borehole, then you‘ve lost all the fuel you need to make the borehole. you‘re ultimately fuel—limited. you‘ve got a certain number of drums that we can use and once that‘s gone, it‘s game over. with the snow melted, it is time to start drilling and that involves unwinding the longest hosepipe you've ever seen. threading the hose through the wench, goes around this capstan and then that drives the hose up and down the hole. they fire up the boilers and it is melting time.

this is an historic moment. the first time anyone has tried to drill down through the front of what is the most important glacier in the world in terms of future sea level rises. slowly, slowly, the drill melts a 30cm hole down through tens of thousands of years of ice deposits. you can see it‘s looking 0k. it's not looking bad. probably better than we both expected. after 36 hours, they finally break through to the sea below. mission accomplished. now it is time for icefin to take centre stage. as it‘s lowered through the glacier, the team ready

themselves to pilots the robot submarine. it‘s more than a mile to where the warm ocean water meets the ice, and along the way icefin gathers crucial data. we‘re driving forward slowly. it‘s a real moonscape. it almost looks like it has craters on it. that is weird. we rolled up on this maybe half a metre of this very clear ice and you could see the sediment—rich ice right above it through the ice layer which was something i'd never seen before. this is incredible. it's seriously like another planet. what is going on? we should let other people know, because this is really cool. are you ready for weird? i'm so excited. get ready to have your brain blown. so this is a clear layer of ice. this part has a bunch of sediment particles in it. but let me introduce you to your new friend.

there is a whole bunch of anenome things burrowing out of the ice. wow! see the little tentacles? piloting your own vehicle underneath the ice is a pretty cool experience. to get to the grounding zone, you can kind of see the water column narrowing, the ice coming down at you, the sea floor coming down to you and there is a huge rush of energy. look at that! singing we do see warm water making it all the way back to the grounding zone, which is changing the base of the glacier right to the boundary zone. we are coming right up to the grounding zone now. no—one else is above us. that's ok, we're the only people in the world right now. we're seeing a whole new crazy thing. that place is really important because it controls how much ice is coming off the continent and at what rate. so taking a vehicle like this right there to map it out

in detail means that we can really start to figure out exactly what is going on. we've been talking about this for seven years, and to finally make it there isjust incredible. oh, yes! that's so cool! because of all the delays, the time spent at the grounding zone is shorter than planned, but icefin managed to complete five missions — one more than expected and collected a huge amount of data. the thwaites team is delighted. this season has been tremendously successful. we‘ve seen the warm water coming up from the continental shelf and making contact with the ice and we have measured the rate of that melt. and to know that we are in a position to begin to understand those changes in a way that actually can

shape the future of policy, and of people‘s lives, that‘s a humbling thing. as we leave, we fly over the main front of the glacier. the epic forces that are tearing the ice apart are all too obvious here. in some places, the ice has broken up completely, collapsing into a jumble of icebergs. i‘m surprised, myself, sitting here thinking about it, how emotional i am. i think it is, yeah, it‘s shocking and we should all be upset by what‘s happening here. do you come away feeling upset that what you‘ve seen is a process of destruction, of destroying a huge body of ice? no, ifeel like i understand the planet, hopefully better. it‘s better to know how things are happening than to guess at it, or to hope it goes away. we know there‘s been change that we‘ll have to accommodate, and this story is about how do

we get together and try to fix things to make the world sustainable for ourselves and future generations? hello. the new year has started on a decidedly chilly note, and i suspect it‘s going to stay that way for quite some time. this is the reason why. this is where we are expecting the jet stream to be over the next ten days. you can see throughout the jet stream will be digging to the

south of the british isles, and that will keep us in the grip of some pretty cold air. so expect temperatures to stay below average throughout the next week to ten days with frost and ice by night, and a mixture of rain, sleet and snow at times, but not all the time. saturday dawns with high pressure to the west, and low pressure to the east. that is bringing a northerly wind across the country. and we are going to see some wintry showers, particularly in areas exposed to that northerly wind. so parts of northern ireland, parts of pembrokeshire, cornwall, northeast scotland, the east coast of england, some of the showers across eastern england will start to drift a little further inland through the day. elsewhere, some spells of sunshine but temperatures struggling, 2 to 5 degrees at best. now, as we go through saturday night, that area of showers moving from eastern england will drift across the midlands into wales, that could give a brief covering of snow in places, and then as we move out of saturday into sunday, a subtle change. 0ur area of high pressure moves from the west towards the north.

it changes shape and that changes the wind direction. the winds not coming down from the north anymore, but coming in from the northeast. still a pretty chilly wind direction, but it focuses the showers across eastern areas. not as many showers out west with a bit of shelter, those temperatures though still struggling around 4, 5, or 6 degrees. and we keep a similar set up through sunday night into monday. high—pressure to the north, notice the white lines, the isobars coming from the northeast. that‘s where the winds will be coming from. quite a brisk wind, actually, on monday. just accentuating a chilly field. i think we will see areas of cloud with some rain, sleet and snow drifting across parts of england and wales where it will also be pretty windy. not as windy for scotland and northern ireland, and the better chance of staying dry here as well. but temperatures on the thermometer, again, around 3 to 6 degrees but factor in the strength of the wind,

this is what it will feel like. in some locations it will feel subzero all day long on monday. and as we look ahead to tuesday, well not much changes. we keep this northeasterly wind, particularly across england and wales, maybe not quite as windy by this stage. could be a little bit of rain, sleet and snow around at times. a decent amount of dry weather too with some sunshine and highs of 3, 4, or 5 degrees. now, we may well see a bit of a change through the middle parts of next week. 0ur area of high pressure looks set to retreat westwards allowing low pressure to develop up to the north. now, there‘s some uncertainty about the timing by this stage, but we will be keeping our eyes to the northwest of the british isles for a frontal system. could well push and across parts of northwest scotland late on wednesday. some rain, the area is pretty cold. there is likely to be some sleet and some snow next again with that. and all signs are that through the end of next week, and certainly into next weekend, the area of low pressure from the north will win out. diving southwards and then taking up residence close to the british isles. that will keep us on the cold side, and it does give a

greater chance of seeing some rain, sleet and snow at times. not only over the hills, but even at low levels.

this is bbc news with the latest headlines for viewers in the uk and around the world. the united states has passed a grim milestone in the coronavirus pandemic, recording more than 20 million cases. research confirms the the new coronavirus variant discovered in the uk has a much quicker rate of transmission. if the new variant is now present, with this increase in the r number, all of a sudden instead of this decrease of 30%, we get a massive increase, the number of cases over the all primary schools in london are to remain closed for the start of term, after a u—turn by the british government. the us senate has delivered a rebuke to donald trump in the dying days of his presidency, overriding his veto of a defence bill. a new era begins, as the brexit transition period ends and the uk completes its formal separation from the european union.