An Antarctic expedition on the RRS Sir David Attenborough

We’re now going to hear from someone onboard the RRS Sir David Attenborough - which is one of the most advanced polar research ships in the world. It is currently voyaging deep into the Antarctic Circle, through waters that - until recently - would have been almost completely sealed by ice. It’s a journey no British ship has made since Sir Ernest Shackleton’s Endurance became trapped and sank more than a century ago. But now, as the ice retreats, new routes are opening - and with them, new stories. ITV News Science Correspondent, Martin Stew, is the only journalist currently on board the RRS Sir David Attenborough - which was originally called “Boaty McBoatface”…

Martin - That's what everyone gets very excited about. Yeah, Boaty McBoatface, you remember the naming competition? Technically the scientists might be a bit cross because it is the Royal Research Ships at David Attenborough. And it's also the UK's biggest floating laboratory. So it's sort of amazing cutting edge ability in that it can break through the sea ice, but also amazing scientific ability. It's got tens of kilometres of cable for dangling scientific probes and stuff off the back and 14 different laboratories on board. So they can do all sorts of stuff, not least in giant freezers, carry things back to Cambridge where they can then analyse and work stuff out further.

Chris - How big is the boat itself?

Martin - It fits about 90 people. It's a large ship and it can deal with some pretty serious stuff. It travels around, covers the Arctic and some seasons comes down to the Antarctic as well. So it gets all over the place.

Chris - And what's your reason for being there?

Martin - Well, I got a message from British Antarctic Survey which said, would you like to go to Antarctica? And I said, yes, I would love to. Then it sort of transpired it was this incredible opportunity because, as you alluded to, no British research ship has been this far south, this late because of the polar winter at the moment in the season. And the reason they're coming down here is to get a sort of a scientific snapshot of what it's like. But the very fact we're able to be here at this time tells a really stark story of what's happening with the climate. Those who know their history know the story of Shackleton. The Endurance got trapped in the pack ice. It got crushed. It sank. The men lived on the ice for nearly two years and then were rescued. And yet here we are, the furthest south since then, and we're sailing through pretty clear waters, to be honest. Yes, there is ice around. You have the captain keeping a close eye on things. But we've seen this amazing shrinking of sea ice around Antarctica. The scale is incredible. So if you look at sea ice data from 30 years ago and you compare it to now, we've lost about one and a half million square kilometres of sea ice. I know what you're thinking, Chris. How many times bigger is that than the UK? And the answer is six.

Chris - We're known, actually, Wales is the SI unit of size for land mass, isn't it? So you need to put that in Wales equivalents, if you could. But basically, it's a lot, isn't it? So we're losing a huge amount of ice. And is that a permanent loss, or are they saying as the winter progresses, because it will, I mean, we're not peak there yet quite, are we? And it gets colder before it warms up again. Will it re-establish or is that ice gone for good?

Martin - Well, when you look at the graph, which is a kind of a curve that goes up the numbers and goes down, where last year's sea ice wasn't and where we're tracking is significantly below that. So it never catches up with where it was. So yes, the quantity of sea ice will go up, but it won't go up as high as it was 30 years ago. And I was talking to scientists on board, what is it about the sea ice that is really important? Because obviously, it's only frozen seas. If you're talking about sea level rise, you might think it doesn't make that much difference. You're just freezing the sea and then it melts again in the summer. But the main thing seems to be that it acts almost like a blanket around Antarctica. So when you have sea ice over the sea, it does a couple of things. First of all, it is a huge amount of white. So it reflects the heat away from the planet. And the second thing is the ice is a cap. It stops the stirring up the ocean. And so when you have less sea ice, more of the ocean can get stirred up in the winter and that releases more heat and more carbon from deep down in the ocean. And then the final thing is that the sea ice acts as a buffer, almost protecting the glaciers which terminate in the sea from the sea. And what we're seeing on this mission particularly is sailing through uncharted waters, getting close up to these enormous ice cliff fronts, which are the front of these glaciers, where they have maybe thought they weren't particularly deep, as we're using this radar equipment mapping the bottom of the ocean, they're able to see that some of these go down about 200 metres, this huge cliff of ice going underneath the water. And that's really important because in the winter, obviously, air temperature will be below freezing, but the sea temperature isn't. So it means all that ocean front, all that glacier front that's in touch with the ocean potentially is melting throughout the winter, as well as the summer.

Chris - What do the scientists make of this? I mean, obviously, it's through conversations with them that you're imparting this. Are they shocked? I mean, are they saying, I'm really worried now I've come here and seen this?

Martin - Well, they obviously are looking at data the whole time, but to see it with their eyes, it has been pretty stark and reaffirms the models which they are creating. And it's worth saying because whenever we do climate stories on ITV, there's often pushback from people saying it's scaremongering and people flagging that Antarctica has gained ice mass over the last two years. I sort of put this aside to say, where does this sit? And they said, look, you're right, it has in the last two years, but that may be an anomaly based on large amounts of snowfall. When you look over long term data is the most important thing in climate science. Over 20 years, the trend is that ice level is going down. So this two years, yes, it has gone up. Maybe that will continue a little bit, but it seems to be a correctional blip. And the trend is still, unfortunately, moving very much in the wrong direction.

Chris - What else are they looking at? Because that ship that you're on is completely festooned with amazing, as you say, there are lots of laboratories on there, but lots and lots of analytical equipment. So no opportunity can be missed when you're down there. So what else are they sampling? What are they looking for?

Martin - Yeah, the other stuff they're looking at is they're doing core drilling into the seabed itself to see what nutrients are and what's in the seabed. And they're really interested in that nutrient mix, because as these glaciers fall into the ocean, they potentially release lots of different nutrients, particularly iron, which is a really good driver of life in the ocean. And the other thing anecdotally we've seen when we're down here is a huge amount of whales. In one day, we counted 115 humpback whales, sensational, beautiful wildlife. And they're a good kind of guide of the fact there must be a lot of krill and life in these oceans at the moment. And so it's an ongoing bit of work to see exactly what impact the melting ice is having on the ocean, whether that's a positive for some species, whether it's a negative for some. But they're trying to build this picture. So that's another thing. A lot of the analysis of that will be done when they take these samples back to Cambridge, and they can run huge data sets and get a much clearer picture.