World's oldest Antarctic ice being melted to find out more about climate | BBC News

Now, the last and oldest sections of the ice cores brought back from Antarctica are being melted for analysis at the British Antarctic Survey in Cambridge. Once all of the results are collated it will give scientists a continuous environmental record going back more than one and a half million years. Our science editor Rebecca Murrell is there for us now. Hello to you Rebecca, this is fascinating stuff. Just tell us what this old ice can tell us about the world. Yeah, I mean it's been a hive of activity here this morning and for the last six weeks because scientists here have been working around the clock to study some of the most precious samples collected from Antarctica and it all starts here in the freezer. So we're going to go in, it's minus 23 degrees so we're not going to go in for too long because all of our kit stops working which makes it a bit more exciting. So this room was packed full of boxes, now there is only a few left and they've saved the best till last because these are some of the oldest ice cores that have ever been collected. One of them is being prepped right over here by Maddy at the moment, it is very clear and this is about to be melted. So we're going to go back outside into the warm, I will make sure that we close the door behind us because we don't want it melting too soon and I will take you over, that's nice and closed, over to mission control which is essentially these screens here because all of the time that the ice is being melted it's being constantly monitored by the scientists here. Now I'm joined by Dr Liz Thomas who's head of the ice core team here. Just tell us how precious these samples are, where were they collected from first of all? These are really valuable pieces of ice that we're currently melting and they come from a core that was drilled in East Antarctica over many seasons, it's part of a big international collaboration funded by the EU and the reason we're so excited about it is because we hope it's going to be the longest ever continuous ice core spreading back at least 1.2 million years, maybe a bit older. And that core came from 2.8 kilometres down, I must just show you this actually the freezer door where you can see the point where they hit 1.2 million years but it might be even older maybe 1.3, 1.4, maybe 1.5. Now let me take you over to here because as the ice is melted the liquid feeds through here into this raft of scientific equipment, there's even a little gizmo here which is collecting the bubbles, the air trapped inside which is potentially over a million years old. Now Liz the ice looks so clear but there's a lot of stuff in there that you're studying isn't there? It does, it looks exceptionally clear and it's very beautiful in fact but that is quite deceiving because inside there we know from using all of these instruments that there is a huge amount of information about our planet, so about the climate and how the environment has changed and what we're doing is measuring that further back in time to be able to reconstruct what's been happening beyond a million years ago. And up to now you've only had ice that's 800,000 years old so this pushes it back way further, I mean why is it important to look back, is it all about looking forward I suppose? Ultimately yes, so our longest previous ice core, the Epoca Dome Sea ice core went back 800,000 years and it was a hugely iconic record because it was able to really place the current increase in carbon dioxide in this longer term context and show that it's outside of the range of natural variability. What we're doing now is we're starting to go even further back in time to an important period in our climate history when we believe that the ice sheets were smaller than they are today, sea levels were higher and we think it may have been that the carbon dioxide in our atmosphere was actually higher, this makes it a really interesting analogue for how our climate is currently evolving and how it may look in the future. It's all about trying to find out what happens next and the only way you can do that is to look back. Exactly. Liz thank you very much, we're going to let the scientists get on with their work here because this is their last day of melting so after that the ice has gone and it's still mind-blowing to me that you've spent you know years collecting this stuff, hundreds of scientists working on it and then essentially to study it you have to destroy it really, but there is still going to be months even years worth of research to continue after the ice has turned to liquid, but yeah really important stuff going on in this freezer here. Rebecca absolutely fascinating, mind-blowing is absolutely the word, thank you for the moment, I'm sure we'll be back to you throughout the day.