Source: BBC Radio 4: Today
URL: N/A
Date: 30/08/2016
Event: Peter Wadhams: computer models are "very, very wrong" about Arctic ice
Credit: BBC Radio 4
People:
Mishal Husain: Over the summer, we've been following the progress of Northabout, the polar exploration yacht that is trying to circumnavigate the North Pole. It's already made it through the Northeast Passage but it has encountered more ice than it bargained for. The crew is led by explorer David Hemplelman-Adams, who's been recording an audio diary for us - here's his latest despatch.
David Hemplelman-Adams: We've gone through several seas, on this trip - firstly the Barents, then we went into the Kara Sea, which was much easier than expected, then we went into the Laptev Sea, which caused us our delays with all the ice, and we were very lucky to actually get through, this year. And oddly enough, looking at the ice charts, it's closed behind us, now. Then we went into the East Siberian Sea, and we've just left it, today. We've just passed the 180-degree mark, which is a really high point for the whole crew, because we're the other side of the world from Greenwich, of course. And now we're in the western hemisphere, and for me it feels as if we're coming home. Slowly, slowly, we're coming home. I think we've gone through all the difficult parts of ice, coming down - we've still got a little bit to our north, we've come down quite a sizeable distance to skirt around it, and hopefully we'll miss that, this evening. And now we're on a straight line to Point Barrow, and if it's good winds, we should be there in a few days' time.
Mishal Husain: Well, Northabout's journey is scheduled to end in October. This year, sea ice in the Arctic has been melting at one of the highest rates on record. It's something that Professor Peter Wadhams monitors very closely - he's Professor of Ocean Physics at the University of Cambridge, and his book A Farewell to Ice is published this week. He's in our Salford studio - good morning, professor.
Peter Wadhams: Good morning.
Mishal Husain: What is your assessment of where we stand, at the moment, with Arctic sea ice?
Peter Wadhams: Well, it's retreating quite fast - it's thinning - the main thing is that the structure is changing. Most ice is much younger than it used to be, it's only less than a year old, and so it's much thinner and it's shrinking in area, so that we can expect that within a few years, before very long, there will be a period in the late summer where it will be essentially ice-free. We can [?] reach that.
Mishal Husain: And when you say "ice-free", just explain - it does not mean that there's, you know, that there is no ice.
Peter Wadhams: No, it means that the basic central part of the Arctic Ocean will be ice-free - it will be possible to navigate to the North Pole. I mean, already, as we've just seen, it's possible in summer to navigate around the outside edge of the Arctic Ocean, which is ice-free and allows you to sail small ships around. But it will be that the central part of the Arctic Ocean will be ice-free, as well. There will be some remaining ice around different - different passages and coastal regions.
Mishal Husain: I note that you said "within a few years" we'll be ice-free in the Arctic. It's a bit different from what what - from some of your earlier assessments. For example, the press release surrounding your book says that by the time it comes out, the Arctic might be - might be ice-free. Do you look back and think that perhaps you've been a little too alarmist, in the past?
Peter Wadhams: No, I don't think so, not at all, because there's - in the world of nature, there are trends and there are fluctuations, the sorts that we have with weather, and the trend has been enormously downwards, the trend towards the reducing area, reducing thickness of ice has been a very strong downward trend, which will inevitably lead to the loss of summer ice within a short time, but we can't specify exactly which year that will be, because we have, from year to year, you have fluctuations due to weather conditions during the springtime, for instance.
Mishal Husain: But in the past, the fact that you have put a year on it - for example, in 2013 saying that it might be gone by 2015 - some of your colleagues in the climate science world have been a bit worried about that sort of thing. Ed Hawkins, for example, from the National Centre for Atmospheric Science, who says, you know, if predictions turn out to be incorrect, then we must acknowledge that, because otherwise we won't be serving the public properly.
Peter Wadhams: No, it's actually - I believe it's the opposite of what he said, because serving the public means telling the public what the data is showing about what is happening to Arctic sea ice. Not serving the public means giving out the results of computer models, which in this case are very, very wrong - they predict that Arctic sea ice in summer will last until almost the end of the century, and if we use that as the basis for our predictions, we're not going to take any of the urgent action that's needed to deal with climate change, and especially to deal with the consequences of Arctic change.
Mishal Husain: And when you say "urgent action", is anything that has already been agreed enough? Can we, for example, on the basis of what was agreed in Paris, reduce our carbon emissions enough to, if not reverse this trend, at least stem it?
Peter Wadhams: No, I think what we're doing is not enough. The agreement in Paris was a tremendous step forward but - in that all of the nations of the world are agreeing to do their best - but the best we can do, which is to reduce carbon emissions more rapidly than we're reducing them now, is still not going to be enough, because there's already too much carbon dioxide in the atmosphere and it has a long persistence time. So my view is: we have to do something else if we're going to really save the world from very catastrophic climate change, and one thing we can do is to put a sticking plaster on it, by adopting geo-engineering methods, which means trying to brighten up clouds, for instance, by putting water vapour into them and making them brighter so they reflect more radiation.
But in the long run, we have to design a way to take carbon dioxide out of the atmosphere, because we've got too much in there, already. And that means inventing methods that will absorb carbon dioxide and - out of the atmosphere, directly. There are methods, but they're too expensive, so a big research project will enable us to find methods that are acceptable, in terms of cost. And that, in the end, will save us, because it's really the carbon dioxide in the atmosphere that is actually causing the warming, so if we take that away, we've solved the warming problem.
Mishal Husain: Professor Peter Wadhams, thank you very much.