 Welcome everybody to press conference number three at the European Geosciences Union General Assembly 2024. This press conference is titled Unveiling Antarctica's Secrets. New research brings us one step closer to predicting the future on the icy continent. We are very excited to have a number of speakers with us today, both here on site and joining us virtually. We are very excited to have this particular section of speakers with us as we are currently in our largest EGU meeting that we've ever had. We've just passed 20,000 attendees this year, so really excited to be able to feature some particularly special science for all of you and your interest. This press conference is co-organised with the British Antarctic Survey in the UK and so I will be running this press conference in partnership with Athena Dina from the British Antarctic Survey, but I would also like to introduce our speakers for today. So first of all, we have Olaf Eisen from the Alfred Wegener Institute, Helmholtz Zentrum for Paula und Miesforschung and the University of Bremen in Germany. We are also joined by Rob Latter, Emma Pearce, Liz Thomas, Alex Brisbane and Oliver Marsh all from the British Antarctic Survey in the United Kingdom. For the information of everybody who is watching online, please can you mute your microphones as we will be proceeding through the presentations in sequence and then you will have the opportunity to ask questions after the presentations have passed. We will take all questions and answers after those presentations. If at this point I would like to hand over to the first of our speakers, which is Olaf Eisen. Thank you very much. Thank you very much. Good morning, everybody. I'm Olaf Eisen, a professor for glaciology and I'm the German PI of the ghost project, a part of the International Thwaites Glacier Collaboration. Ghost stands for Geophysical Habitat of Subglacial Thwaites and we've been investigating the Thwaites Glacier on its landward side over the last two field seasons in Antarctica. So where is Thwaites and why it is so important? Here you see Antarctica and the colors indicate a long term elevation change. So if the surface have been increasing, that's in bluish. If it has been decreasing, it's in reddish and already in the 70s and 80s, some people postulated that the western Arctic ice sheet because of its particular configuration is particular vulnerable to ice mass loss and that could trigger some sort of instability. Since then we have a number of methods deployed, especially from space to use, for example, altimetry or mass budget measurements to understand how much ice the western Arctic ice sheet is actually losing. And in the middle of all of this is Thwaites Glacier. You see here in the yellow circle, which is currently the single most important contributor to sea level rise from ice mass loss in Antarctica. A particular important data set was from satellites with laser altimetry. You just measure the surface elevation and you see the red areas here where most ice has been lost. And currently Antarctica is contributing a very large number to global sea level rise and particular Thwaites contributes about 0.4 millimeters per year. And in order to understand that number, you have to know that we are currently at a rate of four millimeters of sea level rise per year globally from all contributors, not only one glacier. And that has been increasing over the last year. So we were starting off with two millimeters and now we actually reached four millimeters, which is in line with what scientists have been predicting over the last decade. If we go back to the past and look for example at shorelines we see today, which have been real shores in the last glacial or at the end of the last glacial, we can reconstruct the sea level. This is a curve you see here over the last more than 20,000 years. And you see the change of sea level is more than 50 meters here all the way from zero to date to minus four 140 in the past. And the rates of change at that time were reconstructed to be around 40 to 60 millimeters. So this is what we know from the past what is possible. So today we are, as I just mentioned at four millimeters per year, but we know that a factor of 10 more is possible. And this is why scientists, especially geziologists are concerned about the stability of the western Arctic ice sheet. Why? Because it has a particular geometry. It has a bad rock, which gets deeper if you go away from the ocean on the right hand side you see the ocean here, which brings warm water onto the shelf continental shelf underneath the ice shelf. And that is melting ice. So the ice shelf becomes thinner. And the part where the ice sheet starts to float the transition between ice sheet and ice shelf, the grounding line is retreating. And if the bad rock is going retrograde as you see here, getting deeper towards inland site, then this means that more ice is leaving the ice sheet into the ocean. And this is increasing and becoming a dynamic instability. We call the marine ice sheet instability MISU. And the current understanding is that this is most likely what will happen to thwaites later in the future because the ocean has been warming and its grounding line has been retreating and it continues to do so. But it will still be a few decades until we reach mass loss rates, which are really kind of catastrophic. Currently, we still see a small retreat, but still persistent. In order to understand the processes, especially on thwaites later further, the UK and the US started the international thwaites glacier collaboration, a long term program over more than five years with a number of projects of which ghost is one to investigate all aspects of the thwaites glacier system in collaboration also with Germany, Korea and Sweden. And look at it from the ocean side, as well as from the landlord side from the air, as well as underneath the ice shelf. So we try to understand every single component, what is happening right now, what are the characteristics, what are the properties, and what does it mean in particular for the future behavior of thwaites. So how will it change in the future with continued climate warming. So thwaites is kind of the most inaccessible place in Antarctica. It's more than 1000 kilometers from either research station, either the best one, Rathara or the US one, and if you want to go there, the easiest way is you have a big ship and reach it from the ocean directly. What we did in the last season is we flew in to the McMurdo research station with the Hercules airplanes from the United States and Arctic program, and then transferred into a little field camp called Wastey White Camp run by the US. And our some of our British colleagues flew with smaller airplanes and twin orders from Rathara to this field camp and from there, we started after more than a month of preparation at minus 20 degrees with the best traverse. So several traverse vehicles you see here to move from the waste camp on to Thwaites Glacier, which takes another week. So that's basically you're living in the tent while moving all the time. Where did we do our measurements. Here you see a enlargement of Thwaites Glacier, the outline a little bit faint here. This is Wastey White Camp we start from here then go down the glacier for one week and then start measurements down here and within the ghost project we did a lot of different measurements active seismics with explosives radar measurements magnetic lyrics particular seismic measurements I will come to back later and other things. And in the first season, we crossed this along flow line, I will show you seismic image of later down here, which is more than 200 kilometers long. And in the last season, which just finished in January this year, we did this across flow profile. I slow here you see is from right to left, the brighter colors are faster flow and this is a so called shear margin so we have violet colors that's where the ice is not very fast. So this is where the ice cream basically ends. How did we do the wiper seismic measurements. So seismic means you create elastic waves kind of sound at the surface of the ice sheet and the waves go into the ground. You can use explosives, which is kind of a little bit more cumbersome and not very fast. And what has been developed already 40 years ago in industry is a so called wiper seismic method. So you use a wiper seismic system here in a little truck which is on the sled and pulled and that puts down the base plate. You see the imprint here which has maybe 70 centimeters diameter and that signal then generated by this truck goes down into the ice and whenever the properties change some part of this wave. It's reflected to the surface and that's where you get for a single tracey signals. And at the surface we have geophones, which are little cylinders with kind of microphones in them. And that's behind on the one and a half kilometer long cable behind this wiper size truck. And that gives us a very good data set off the ground underneath the ice all the way through the ice and into the ground to the bed of quakes laser itself and looking around 200 meters into the base. And then we repeat that every 75 meters for weeks. It's kind of not that exciting, but it gives you a really good data set so as a scientist you can look at what you did during the day every evening and you're just happy if things work out. So here for this profile we did more than 4000 sweeps. It means one sweep we call that the source the triggering every two minutes. This is one profile along the ice flow ice flow here is from right to left. More than 200 kilometers and on the vertical you see something we call the travel time of the waves into the ice and back. And that corresponds to around four kilometers in total and about two kilometers is the thickness the average thickness of the ice here. So there are a few really exciting things we found is that one you have these really rough Terras. Outcrops which are followed by basins of smoother material, most likely sediments, and then also in these outcrops here's one there's one behind that we see some really nice stratified sediments. And that's something we know from geomorphology on ice on areas which were covered by ice but are not anymore today these are crack and tail features. The sedimentary basins are probably rather soft material. So the outcrops are rather hard and rough. So have more resistance to ice flow and the soft sediments have less resistance. And what you also see is this feature in the ice all over the place, especially where you have more rough bedrock topography. That's where the orientation of the crystals in the ice actually change. So ice is anisotropic we call that. It has not the same properties nor directions. And if ice is flowing over these rough areas, there's a lot of stress on them and rotates them. And that's important if you want to understand the dynamics of the ice sheets because the ice is 10 times harder in one direction than 10 than 10 times in the other direction. So it's a difference of around 100 in terms of hardness or softness of ice. And that's something you have to consider if you model that. Another thing we found in the last season which it finished in January. This is now the across flow profile. You see here the flow is into the page one more than 130 kilometers wide again around two to three kilometers here in the profile. We have one area where we have very transparent features underneath the ice. So this is the underside of the ice and then we don't see anything and then all of a sudden we get nice reflections back. In these transparent areas we interpret either as large bodies of water. So you could consider them as lakes or sediments which have a lot of water in them. So a high porosity and a very, very soft sediment. And this is something which has been postulated before and now it's the first time we can really see what does this material actually look like. And with that, I hand over to Rob. Okay. My name is Rob Lata. I work at British Antarctic Survey. I'm a marine geophysicist. I was one of the original PIs of the Thwates offshore research projects. And a couple of years ago I joined the science coordination office of the International Thwates Glacier collaboration. So I have some complimentary data to those that Olaf has been talking about offshore seismic data that shows some of similar features. And what we also have offshore is detailed bathymetry data collected with multi beam echo sounders on the American ice breaking research vessel than Nathaniel B. Palmer. So in the top left of this slide, you see the multi beam echo sounder data, which is almost complete coverage of Pine Island Bay, the area in front of Thwates Glacier. And this shows what the rough topography under Thwates looks would look like. If you had complete echo sounding coverage of it, you can see these rougher features, these crag and tail features, in a way that it's very difficult to acquire data under the glacier itself. So the data that Olaf has been presenting has been collected with a great deal of effort over two field seasons. On a ship, the ship continues to go forwards, it's about 10 miles an hour all the time collecting equivalent sorts of data. So offshore, we can collect, it's still not easy because it takes a week to get here from South America. And you have to navigate around icebergs and so on, but we can collect data offshore a lot more quickly. And we're looking at the bed of the glacier is already retreated from. So this can give us some insight into what the bed of Thwates Glacier would look like if we could take all the ice away. And this is incredibly important for ice sheet models. Ice sheet models need to know how rough the bed is and what it's made of because a glacier like Thwates moves forward mainly by sliding. And it's what the controls on that sliding are that will will govern how fast the ice actually retreats in the end. And we also have offshore seismic data recently collected using an air gun source using releases of compressed air into the water, which is the surprising thing that has revealed is that in Pine Island Bay in front of Thwates Glacier and Pine Island Glacier, we find a lot more sediment than that has been described before. Using just sonar transducers that in some sediments, they can penetrate a little bit into the seafloor. The seafloor looked very hard over most of this area, but using something a lower frequency source that penetrates better into sediments, we find now the true distribution of sediments. So we see things in places like those stratified sediments on the backs of Crag and Tail features that Olaf described. But the section I'm showing here, it shows a particularly thick accumulation of sediments in directly in front of Pine Island Glacier, which is in many ways a similar glacier to Thwates. And I think what this is telling us is that the last stages of retreat of Pine Island and Thwates over the few thousand years before the 20th century were actually very slow because if a glacier is putting out a continuous delivery of subglacial sediments, then there's an inverse relationship between the thickness of deglacial and proximal sediment that you will find and the retreat rate. So I think these very thick sediments we see in front of Pine Island Glacier are confirming what we already suspected from radiocarbon dating of marine sediments that the last stages of the retreat were actually very slow until we get to the mid-20th century. So what we did find we just described, what are the implications of that? We see that there are soft and smooth basins and that means at those places ice flow is usually thinner and fast. Where we have hard and rough bed, it means that ice is usually thicker and flows slower. When we have water bodies underneath the shell or underneath the ice sheet, it means there's no resistance at all. And we have the strong anisotropy, which means the ice hardness and softness varies. So in order to be able to predict or project the future behavior of Thwates Glacier, especially the retreat of its grounding line, we have to consider these local conditions, how much they vary. And now we have these very great similarities between offshore data, which covers a large area, and our onshore data. So we have a broad spatial coverage. And this is now the next step to bring these together to kind of reconstruct the properties of the bed underneath Thwates bringing both data sets on and offshore into a single perspective. And that's something which ice dynamic models have to take into account in order to decrease the uncertainties for our projections of future sea level rise from Thwates Glacier. And not only that one, but also the neighboring glaciers like Pine Island and with that actually the all of Western Arctic ice sheet. So with that we are done. Yes, thank you Olaf Eisen and Rob Latter. We will now pass to Emma Pearce and Liz Thomas. Good morning. Thank you for coming. So my name is Emma Pearce. I am a ice fracture geophysicist at the British Antarctic Survey. And today I am going to talk to you about our project Rift it, which is the rates of ice fracturing and the timing of tabular ice production. And with that I'm going to tell you how we as glaciologists and scientists are hopefully one step closer to predicting iceberg carving or the process of ice breaking off and forming icebergs that go into the sea. So I'm going to start by taking you to the run ice shelf. So this is where myself and Liz spent the last three months is in West Antarctica in the north. So the opposite side to where Olaf has just been showing you this tent that you can see in the front is an ice core drilling tent. And this is where myself and Liz spent most of our time drilling to a depth of 110 meters to recover these ice cores that are really going to give us this new insight into ice fracture and breaking of the brunt ice shelf. In the background you'll see Halle 6 research station. This is the name might sound familiar to you because it's a really cool station that is built on skis. And in 2017 it was moved 23 kilometers upstream of the ice shelf to account for the evolving processes of the brunt ice shelf. So why as ice fracture geophysicists are we interested in the brunt ice shelf? So today we've got a great research station there that has allowed us to have access to information for the last 50 years. It's one of the most highly monitored ice shelves in all of Antarctica. We've even got data dating back to 1914 when Ernest Shackleton went past on his trans Antarctic expedition and made notes about the extent of the ice shelf and the brunt ice shelf at that time. It's a very active ice shelf. So in the news in the last few years you might have heard about iceberg A74 that broke off on the north. This was around 1300 square kilometers big so the size of Greater Paris if anyone knows how big that is, you do now. And then in 2023 we saw the final car like finally saw the carving of iceberg A81. And this was particularly interesting to us because that's actually what caused us the British Antarctic Survey to move Hally 6 research station those 23 kilometers. So that was because of chasm one which was first noticed around the 1970s. This is a big ice fracture that formed in the brunt ice shelf. And it was relatively stagnant for 30 years it didn't really do anything. And then in 2012 it started to grow northwards again, which caused to this moving of Hally station and slowly up green north and eventually in 2023 it penetrated its way through the whole of the ice shelf and allowed iceberg A81 to be free. And that for anyone who is interested is the size of Houston or Greater London for any rates in the room. So although we've seen these like two icebergs carved it is still a very relatively active ice shelf. So we now have Halloween crack that is propagating in the north and chasm two which is in this sort of dormant period that chasm one was previously in. And the yellow triangle show you the field sites that we have been at over the last few years. And these are the areas that we're going to collect data to really try to better understand this process of ice fracturing and evolution within an ice shelf. Ice shelves themselves are quite interesting because they do this natural process of growing and evolving and flowing into the sea and carving, which is how they behave but in some areas in Antarctica we've seen that with our changing climate there's sort of been an instability induced in this. And that has led to them sort of flowing and carving away an accelerated rate which almost acts as a caulking a champagne bottle that allows ice to then flow into the sea and accelerated rate and can lead to an increase in sea level. This is something that's not particularly well understood the processes associated with that. And for us to be able to reduce our uncertainty and sea level predictions, we really need to get a better control on that and that is where we come in. So this next video is showing you Halloween crack from this winter. So we were here for around a week after leaving Halley research station, and the aim of this was to try find where the current end of Halloween crack is. So we could deploy instruments that could hopefully detect these small scale fracturing of the ground ahead of the active rift and really understand and characterize those properties that are happening. The overall process of ice fracturing is well documented. We know when ice bugs have or ice bugs are carved in the past, but what we don't understand as glaciologists is the very small parameters that control this process. And that is where we come in using geophysics and those ice cores that we drilled on the brunt ice shelf to give us the next insight into how that process happens. You can see us there on our skadoos doing radar data to try to see the subsurface and then here is myself and our field guide walking along what we assume is like the very end of the fracture of Halloween crack, trying to get the precise location of where it ends. So we know that the ice ahead of that fracture is underserved and the ice that we're looking at is in that process of changing. So the Rifted project, similar to the Swates project, I suppose it's using all types of data, but uniquely it's using ice core data with geophysics data to give us an insight into the surface of these ice properties and the subsurface. It's a great opportunity to be able to combine these two datasets that often isn't done and it gives us the very small scale properties of ice fracturing, along with a more broad scale view. And with that I will hand over to Liz who will talk to you about our ice core drilling from this season and the data that we got there. Good morning. I hope you can hear me. And so my name is Liz Thomas and I'm head of the ice core research group at British Antarctic Survey and my role in this project was to use my expertise and knowledge of drilling ice cores around Antarctica to go and collect two cores from the brunt ice shelf. So ice shelves are really important. They're this floating tongue of ice, but it's not uniform. So we have areas of ice that have broken away from the continent, which we call continental ice. But we also have between these sections of sea ice and then a layer on top, which is the fresh snowfall that has then become compacted. So what we were really interested in it was to actually go and sample the different types of ice and we're using the ice in a very different way here. So it's quite exciting because rather than using an ice core in a traditional sense to look at past climate. We're actually looking at the ice and thinking of it more as a fabric and looking at its mechanical or structural properties. So the first core that we drilled was down to 110 meters. And so this is quite exciting because actually we were drilling right down below sea level so we're actually nearly 90 meters down underneath the level of the ocean. And there's the short video clip that you just saw there is how we drill this so we do this in small sections we have an electrical mechanical drill and then a small team so Emma and myself with help from other people on the station. We drill these in sections of around about a meter each time pulling up the core, carefully extracting it to bring it back to the laboratories. And then we essentially use this approach and repeat it 100 times to get down to the bottom of our core. So the interest and the the area that we're looking at so we've got these two very different types of core one of which is going through this continental ice, and one of which was into the snow. And then we've got the brine infiltrated Fern, which connects these sections. And on this particular core the 37 meters deep core we were actually approaching the level of the sea ice underneath. So we're extracting cores that were very salty and actually very dense because you can see that they've been infiltrated with this sea water at the bottom. There's an interesting comparison between the two ice sites, which is going to provide really fundamental information for the modeling part of this project to really understand the structure and how the different structure and potentially the impurities within this ice determines how the ice fractures. We just moved to the final video I'll talk through. Thank you. So here I'm just going to finish off by taking you on a journey down into the ice shelf. This is the site where we drilled 110 meters. So we're speeding up through here and this is what the compacted snow and Fern. So this is a snow that's fallen in recent decades. And you can see some of these are we're going quite fast but some of these flashes here of darker layers are actually where we've got surface melting so at times the ice shelf does actually get quite warm. And as we start to go deeper down through the ice, this is where we're going through this transition now from the snow into this continental ice. So this is notably a very different structure incredibly hard compared to the Fern above it. So you can tell this with the drilling and some of these really interesting features hopefully you can see in the video here are what we were terming melt veins. So this is where the ice as it's float off of the Antarctic continent has then become exposed probably to the surface and had some surface melting which is what we can see as these features that actually seem to propagate quite far down through this ice. And so just at the bottom now we've stopped and we're sitting now 110 meters deep, which is interestingly as I said there's only 23 meters worth of snowfall sitting on the top so we're actually below sea level at this point. And the important thing is is that, you know, what makes this project so different is that people have drilled through ice shelves before. But normally it's to drill a hole in order to obtain information from either the sediments beneath or the ocean beneath. But what we're interested in is actually collecting and protecting that core from within here to take it back to the bar the bar tree so the ice is currently on its way back to the UK, where we're going to look at it at the labs at the British Antarctic Survey and also University College London to look at its fabric look at its structure and hopefully provide some really interesting and insightful data that can be used in the models to predict how and why the ice shelf is actually fracturing. Thank you. Okay, thanks very much everybody for your presentations. That was really interesting. For those of you online and in the room I'm Athena Dina I work as the deputy head of communications at British Antarctic Survey, and I've been doing it an awfully long time and I love, I love all this stuff get really excited goose bumps when I watch videos like that so I hope you enjoyed it as much as I did. Great questions now so questions in the room and questions online which will be coming through to Hazel. The people online who can answer questions have been introduced but we've also got Ted scambos from University of Colorado in the room who won't be able to see. I'm afraid if you're online but he can answer questions and just to say he was very much involved in the sort of conception of the International Thwaites collaboration probably more than a decade ago. So any questions about future is something that you know Ted might be able to answer as well. I just wanted to add one thing about thwaites and it's something that actually that Rob said to me yesterday and he that we've alluded to but I think he just said the biggest uncertainty from Antarctica and its contribution to global sea level rise comes from thwaites glacier. So just to give you some context, wait, we've said it's important. It is. It is really, really important. We have a press release on these two different stories. So if you're joining us online and you haven't had a copy of that, please contact the press office and we can send you in there. There are links to footage that you have seen in the recent presentation but also we have some lovely footage that Olaf got from the traverse on thwaites as well. So if you're interested in broadcast images, both stills and video, we've got those. So, yeah, right then over to questions. Shall we start with questions in the room? Do we have any questions? Okay, we start with you, Michael. Hi, thanks very much for the presentation. Can I ask you, Olaf, can you sort of cut to the chase and say, you know, that your findings of the terrain underneath thwaites is this good or bad news? Is it better or worse than you expected? Can you sort of say anything about the implications for ice loss in the future? At this stage, the latest data is a three month old. I would not be able to say it's good or bad, black or white. So we need a few, well, probably a couple of years to really look into these data and very much detail. We get a first glimpse. We know what we are seeing there in the general sense. But now the tricky part is to transfer our new observations into a way where they can be used by models. And then our colleagues, the ice flow modelers, can use these boundary conditions at the base to run their models and see, okay, how much different is it actually that we know what is down there? Or that we also know that the viscosity is not the same all over the place. Currently people use the surface velocity to estimate what the sliding is over the bats using some sort of mathematical approximations. And that's kind of an inverse approach we call it. And now we can say what is down there. So they, we can reduce the uncertainty. We can take out one unknown from the equation and then have better projections. And then after that we can say, okay, it's better or worse than what we had before. But in any case, we will be able to reduce the uncertainties, which brings us just back to what Athena mentioned, that the uncertainties for the behavior in the future are still quite big. It's not like that we're don't know at all what it's going to do, but still there's room for us now with these observations to decrease these uncertainties. And that's important for the people who are actually living at the coast, especially those people who are concerned with the security of the coast. Building dykes, whatever that they know a few decades in advance, what they can expect from Antarctica, which is in particular important actually for the northern hemisphere. So green and ice is more influencing the south and Antarctica the north. And then be prepared to the average sea level rise plus storm surges to reinforce the dykes and adjust in time. And if I may ask another question, I was intrigued by these possible lakes. Why would there be liquid water so far down? How long has it been there? Could there be life in it? How do you find out if it's really water? Are you planning to drill down there? Well, we've been knowing for quite some decades now that there are a number of lakes underneath Antarctica. By now we found more than 400 by different methods. You can observe actually from satellite altimetry, laser altimetry, like if lakes are draining, you have a strong decrease in surface elevation. That's also what we observed at one lake on Thwaites. And then you can also see how they fill. So they're sub-laser floods. It's really an active hydrological system. And they are just created by, on the one hand, the heat coming out from the earth like you have if you go down into a mine. It's also getting warmer the deeper you go. And then you've got the ice sheet on top, which is a very nice insulator. So it's kind of trapping the heat. And then you've got also the ice from the surface. It's falling in form of new snow and going down, flowing down. So that's bringing cold down in a certain way. So that's how you trap the heat down there. And if the ice is thick enough and the conditions are right, the ice will just melt and then will form either a thin layer of water or it will go into the sediments. Or you can actually have lakes like the largest lake on earth is actually Lake Wostock underneath the East Antarctica ice sheet. And the ice has been there in Antarctica for around 34 million years. And it's very likely that some of these places we also had water since the very beginning. West Antarctica, the question is, was the West Antarctica there in the last interglacial? So more than 120,000 years ago or not, we have some indication that it was gone. So the water is probably not older than the last interglacial. Is there life that has been investigated and a number of projects to try to drill into subglacial lakes? For example, in the Western Antarctic region into subglacial Lake Willens, you have usually some sort of life down there. The farther away from the coast you go, the less evolved it is, but close to the shelf edge. So the grounding line, you still have fish swimming around four or five thousand kilometers from the coast away. So it's basically like a deep abyss, but not 10 kilometers deep. It's just that maybe thousand meter water depth. Just to add to that, we did a press release a few years ago about some drilling that was done at the grounding line and there were all kinds of life. And we've actually got some video footage of all these things floating. So, yeah, it was a real surprise to those that were drilling. Do we have any more questions in the room? Yeah, so Michael's got. Oh, is it that? Okay, well, Michael, you take your question. We'll just check the audio is working and then we'll go to the questions online. Hi, a question for you. I just, I wonder if you could explain. So I thought that ice shells were formed by ice sliding off the land to the ocean and we're just purely that ice. But from what you were showing, it seems to you as a show into the sea ice and Brian penetration. I wonder if you could just explain how that comes about. So as the ice flows off the continent, often it can sort of break up into icebergs that are then essentially glued back together by sea that freezes and sticks it back together. And over time you have this snow that then falls on top and forms this fern. So this process of snow transitioning into ice. And on the brunt we end up with this topography of these lumps of continental ice these big chunks that have broken off and maybe they've had surface melt when they broke off and then rotated. And that's what we think could be causing these veins in the ice shelf when we see them. And then they are all glued back together with the sea ice as it comes in and freezes. And then we have this snowfall that lands on top and makes this very solid lump of an ice shelf that then flows out. Okay, great, great timing. Thank you for that last question. Okay, so we've got a question online from Nick Perry from AFP Nick. Would you like to go ahead with your question? Hazel is going to ask your question, Nick. So I see you've written it in the text. So Nick would like to ask, could I please ask Olaf or Robert to elaborate further about how important thwaites is in terms of contributing to global sea level rises and how these new findings aid our understanding about how it might behave under various future warming scenarios. Good question. Would you both like to talk to that. And then we can also invite Ted. Would you like to talk to that? Okay, hi, I'm Ted scambos from the University of Colorado. I had a lot to do as Athena mentioned with the initial proposals that went in that were put together and made the international thwaites. Glacier collaboration. Going forward with weights under various scenarios. What it looks like is that the glacier will continue to retreat and contribute to sea level rise. However, the pace of it could be extreme could be dramatic or it could be more manageable. And what we've learned from ITGC so far is that some of the most extreme cases and some of the processes that we were particularly concerned about when we began the ITGC pro collaboration are less likely to take hold in the near future. We still have this problem as Olaf pointed out in his slide of the marine ice sheet instability, which means that the fundamental geography of thwaites glacier is such that it can be unstable and indeed did probably collapse in the last interglacial period. So we have to watch it closely. We've uncovered a great deal more information about a number of processes. That pertain to thwaites glacier. We want to continue to look at it. But some of the things that allowed for thwaites to be this extreme case before the end of the century in terms of sea level rise. We think those are less likely, but we want to continue to look at the system and understand it better. I can answer that. Okay, well, yeah, do you want to add to that? Yeah, so I think it's incredibly important for understanding global sea level rise. So from when we had the first satellite altimetry data in the early nineties. At that point, this sector of Antarctica with thwaites glacier and pine island glacier in was not far out of balance. It was only contributing a little bit more ice to the ocean than it was accumulating over a period of 30 years. We've seen that imbalance progressively increase. So although, as Ted said, we're not looking at some of the most catastrophic projections that have been made. The mass loss has increased dramatically many times. It's many times what it was in the eighties now. And there's no suggestion that it's not going to continue at that high rate. It's now from this sector of Antarctica, as I've said, that now contributes about 10% of the current rate of sea level rise. And that that's increased from a much smaller percentage 30 years ago. We don't certainly don't envisage it going back down. It's probably going to continue to grow. The question really is, is how fast it's going to, it's going to grow. And our projections of that will get better as results of the kind that Olaf has described or incorporated into the latest ice sheet models. That's a good point, right. I would like to add to that. Although we have some uncertainties here, if you look at the projections we have right now. There's a physics on the one side. The other one is society, what society is doing, and you see a tremendous difference in the way these systems are reacting to climate change. If we're on a path towards 1.5 degrees, which we might, Paris Agreement, if you might reach probably in the next five years in this decade, or on two degrees by 2100 or three and a half degrees makes a big difference. How fast these systems really act. And the problem is, once they have reacted, once they crossed the tipping point, it's not that easy to bring them back. It might take hundreds to thousands of years, even if you call the climate to bring them back. And that's also something which is discussed here during the general assembly quite a lot. And this is also where not only the physics is important, but actually what society is doing. So there's no question we have to mitigate climate change. We have a question in the room, maybe we'll take that question. And then have I got the Ted, could you pass the microphone. Yeah, thanks. Yeah, thank you. I have a question, maybe to Rob. I was wondering the total recent news about CIS decline around Antarctica, very dramatic in the last, yeah, last past year. How does that affect the inflow of warm deep water that is ultimately causing the retreat of the ice off of Swades Glacier. And how worrying is that actually. I think it's very worrying. Really, that's a question for a physical oceanographer. I'm not. What I will tell you my understanding of it is, as the sea ice is formed, it would brine is rejected the sea ice is fresher than the water it's formed from. So you concentrate the brine in the water and you chill that water. And what we see in Antarctica is we form this layer of cold salty water called the winter water. The more sea ice you form the deeper that gets through the winter, which, and that that in that is an impediment to warm water getting on the shelf the deeper the winter water, the more difficult it is for for warm water to get onto the shelf. So if we're forming less sea ice, the that cold layer will not not penetrate so deep, we'll have more space for warm water to come onto the shelf and several different ocean models that have come out over the last year or so have projected an increased amount of warm water coming onto the the the shelf of West Antarctic, the continental shelf of West Antarctica as we go through this century, which is obviously not good news. Okay, thank you. We have a question from John Amos BBC online. I understand that you can hear us but we can't hear you so Hazel is going to relay the question. Yeah, so John asks, can we have layered versions of Olaf's topography graphics, so we can reversion for publication. Layered versions. Edible. Okay, yeah, I think we can work on that and get back to him directly. Lovely. I also have a question for Emma slash Liz. Just to confirm, you didn't drill all the way through the shelf and stopped when you got to the wet ice on the underside of the shelf. I didn't do that. That was the drill would almost form a vacuum and you wouldn't be able to pull it back out so we did not go all the way through to the water underneath. Okay, so as I understand it there are no more questions online and any more questions from the room. I can have a go at answering your brunt question if you want to say do we want to try. Could Oliver try speaking do we know if we can hear. Can you hear me. Yeah, hi. Yeah, so my question was on the flow velocity of the brand ice shelf and and how comparable or how unique that is really compared to other ice shelves around an article. Given the large carving events you observed in the past years. Thanks. Yeah, so the branch of does have historically quite a variable velocity. Obviously we've been monitoring it for a long time so we've we've seen its changes in velocity. It's currently a almost a historical high point. So after the carving of 81. It increased quite rapidly from around 900 meters a year up to about 1500 meters a year. It's dropped off a few hundred meters a year since around September last year, as it seems to start to re ground in an area known as the McDonald ice from force. So the carving that happened in January of last year did lead to a bit of a velocity acceleration and it's dropped off again a little bit since then. But it is, it is a relatively fast area. Considering how it's fed from inland so unlike other fast flowing ice shelves around the continent so places like voids and where velocities would be similar, not higher. And some of these other fast flowing ice shelves, the point I show doesn't have these fast flowing glasses feeding it from the continent. There is slightly an unusual I show it in a number of ways. But yeah, the velocity at the moment is decreasing slowly but still historically higher than it has been for the last 50 years or so. I have another question for Olly from John Amos online and he asks, what is the current velocity of the shelf? Historically, it's been 400 to 800 meters per year. What is it now? Now, at the moment, as of, you know, this week it's 1300 meters a year has dropped from 1500 back in September last year, which was the highest highest it got following the carving. I see another question from Jonathan Amos about. Yes, I'll just ask it just in case anybody else needs to chip in. Another question from John reads, the results of the Brunt study play into the future of Halley, right? The results may tell you that a Halley seven is not wise. So obviously having Halley there on the brunt ice shelves gives us this opportunity to do detailed studies on cracks that wouldn't otherwise be possible. And a lot of our monitoring infrastructure of these cracks is maintained through Halley being there and for operational reasons. So, you know, having a station on an ice shelf with cracks is actually really helping our research into how cracks grow through the ice shelf. The plan at the moment is that we maintain Halley and keep running Halley as it is and keep monitoring the ice shelf. Any future station, I guess I wouldn't be able to comment on that. I can talk to that for a minute and just say that, you know, as Ollie said, having Halley there is really advantageous in a way for our understanding of the ice shelf and also for all the space weather research we do at the station and where we've had continuous data for many decades. But we have a new science strategy and we have a new strategy and the world is changing. We're using AI, we're using autonomous robots in a way that we haven't before. Also, I think it's really, while the traditional methods of doing research will continue, I think we're doing all these other things that are enabling us to get so much more data from Antarctica than we have before. And so quite what's going to happen in 10, 15 years, I don't think any of us know, but I think that the world is changing so quickly and we'll have to keep up and make sure we're getting the best research for the benefit of society, I guess. Any more questions? Anything else from the room? No, thank you very much. And back to Hazel. Thank you very much, Athena. So that brings to a conclusion our press conference number three. This is three of seven press conferences that we have this week at the General Assembly. Our next press conference will be starting at 11 30 this morning and is titled by Joe new revelations about Jupiter's planetary system. If you want to join us, you can either join us online where we will really work hard to fix any of the technical issues we had today. Big apologies to all of our virtual participants and speakers for the disruption that you experienced. And thank you for your patience with that. But all that remains to say is if you need any additional assistance from the EGU press team during the General Assembly, please visit the media dot EGU dot EU web page where we have all of the resources that Athena mentioned before, as well as access information for all of our speakers for all of our press conferences. But the last thing that I would like to end with is to ask you to join me in giving all of our speakers a big thank you for their presentations today. Thank you very much.