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Thursday, May 29, 2014

Peter Wadhams: Melting Polar Ice Caps a "Ticking Timebomb" for Earth's Climate System


Peter Wadhams, ScD, is professor of Ocean Physics, and Head of the Polar Ocean Physics Group in the Department of Applied Mathematics and Theoretical Physics at the University of Cambridge. He is best known for his work on sea ice. Dr. Wadhams is the president of the International Association for the Physical Sciences of the Oceans Commission on Sea Ice and Coordinator for the International Programme for Antarctic Buoys.
Dahr Jamail has written extensively about climate change as well as the BP oil disaster in the Gulf of Mexico. He is a recipient of numerous awards, including the Martha Gellhorn Award for Journalism and the James Aronson Award for Social Justice Journalism. He is the author of two books: Beyond the Green Zone: Dispatches from an Unembedded Journalist in Occupied Iraq and The Will to Resist: Soldiers Who Refuse to Fight in Iraq and Afghanistan.


Melting Polar Ice Caps a ANTON WORONCZUK, TRNN PRODUCER: Welcome to The Real News Network. I'm Anton Woronczuk in Baltimore.
A recent study by researchers at NASA and the University of California, Irvine, has found that a section of the West Antarctic Ice Sheet is melting at an alarming rate and could raise global sea levels by up to four feet. Meanwhile, the Arctic is also showing the strain of global warming, with an ice-free Arctic summer predicted by 2016, according to research by the U.S. Navy. This research comes as the National Oceanic and Atmospheric Administration announced that April 2014 ranked as the hottest April on record, tying with April 2010. It also follows the recent release of the National Climate Assessment that says that signs of climate change are all around us.
With us to discuss why the melting polar ice caps could spell the end not just for penguins and polar bears but for mankind are our two guests.
Dahr Jamail is a staff reporter with Truthout currently writing about the environment and climate change. His recent articles include "The Vanishing Arctic Ice Cap".
Also joining us is Peter Wadhams, who is a professor of ocean physics and head of the Polar Ocean Physics Group in the Department of Applied Mathematics and Theoretical Physics at University of Cambridge.
Thank you both for joining us.
So, Peter, let's start with the recent NASA study on the melting of the West Antarctic glaciers. What are the predictions in terms of the scope of the melting and the effects that it will have on rising sea levels?
PETER WADHAMS, PROF. OCEAN PHYSICS, UNIV. OF CAMBRIDGE: Well, it was a surprising prediction. In the past, until recently, the general assumption was that the Antarctic ice sheet is very stable. The West Antarctic ice sheet is slightly less stable than the East Antarctic ice sheet, which is the much bigger area, but the general thought was that it's quite stable and we don't have to worry about the Antarctic ice sheets, and for a long time, if they contain most of the fresh water in the world and if any part, major part of the Antarctic ice sheet did slide off its bed, then there would be a gigantic impact on global sea levels. And this study predicts four feet as what would happen if this large chunk of the West Antarctic Ice Sheet came off. It's something which is clearly based on very good research. It's something where we might expect it not to happen within the next few years.
But climate change at the moment, which is so catastrophically rapid that something that's going to happen in a few decades, perhaps, which is very quick in terms of Antarctic glacial history, is, as far as the world is concerned, kind of slow, because by then the sea ice melt will have had much bigger impacts on global climate and will be affecting us very detrimentally. So I think the Antarctic, it's much more serious than people ever thought, because people thought we didn't have to worry about the Antarctic ice sheets. So it's more serious than we thought it was going to be.
But in terms of what are the immediate threats to our continued existence on this planet, it's probably the case that sea ice retreat is going to have its impact first, and something happening to the West Antarctic ice sheet is not something that's going to happen in less than a few decades.
WORONCZUK: So what would a four-foot rise mean in terms of its effects on humans and the climate system?
WADHAMS: Well, even IPCC, which is a very conservative body, is now predicting something like a meter of sea level rise this century. And if you--they don't take really enough account of the rapid melt of the Greenland ice sheet. But we would expect from Greenland ice sheet melt and general warming, which produces rise in the level of the ocean because the ocean is itself warming, we would expect, I think, more than a meter in this coming century. So what would happen if the Ice Sheet, if the Antarctic Ice Sheet slid off its bed would be a century of sea level rise in one go. And that would be pretty serious. I mean, we can compensate somewhat for a steady sea level rise by raising the heights of flood defenses and taking precautions against it or adapting to it by retreating from certain coastal urban zones, opening up more wetlands, but if it's happening very suddenly, we can't. You can't adapt to something that's happening that rapidly. So it would be a pretty serious thing if it really did happen like that.
WORONCZUK: So, Dahr, as governments and corporations open up new shipping routes and offshore oil drilling projects in the Arctic, why shouldn't we embrace an iceless Arctic summer as the new normal? Can you explain the role of Arctic sea ice within the Earth's climactic system?
DAHR JAMAIL, INVESTIGATIVE JOURNALIST AND AUTHOR: Well, another thing--and I'm speaking somewhat out of turn, since Professor Wadhams is really the expert here and he can talk more in detail about this--but, you know, the Arctic sea ice is playing a critical role in keeping methane emissions from melting permafrost in check. And as that ice continues to thin and both retreat, exposing more and more of the shallows, Arctic seabeds, to warming waters and solar radiation, as well as continuing melting of permafrost on the shores, it's well documented at this point that intensification of methane release is ongoing and worsening. And so methane, of course, being dramatically more intense as a greenhouse gas than is carbon dioxide-- so it's really causing a runaway feedback loop or a positive feedback loop with anthropogenic climate disruption of really causing the whole situation to speed up much, much more dramatically.
And NASA has done studies on this, as well as Professor Wadhams' group, that basically shows--the NASA study referred to the methane in the Arctic as the ticking time bomb of climate change, that as this continues to ramp up in its release, it's really setting in motion a runaway feedback loop that we probably won't be able to do very much about. It's causing dramatic increases in temperatures across the planet.
And then, you know, another thing that I think we need to keep in mind is that as dramatic as the situation that we find ourselves in today and the rapidity with which climate change is happening and ever increasing, that the 63 percent of all human-generated carbon emissions have occurred in just the last 25 years since the Industrial Revolution began. And we have scientific reports that show there's actually a 40-year time lag from when those emissions are released into the atmosphere and when we actually feel the effects. So that, I think, just underscores the urgency of the situation that we're in regarding that we're literally on the precipice of losing the Arctic ice cap in summer is a situation that once it happens is going to increase, of having a longer period each summer where that's open, and then the massive disruptions in the climate that's going to cause.
WORONCZUK: So, from what you're saying, it sounds like nothing much can be done in the short-term to reverse the melting.
JAMAIL: Well, as far as if we're talking about reducing emissions, you know, I think this really puts into perspective, really, the folly of when we hear governments, particularly that of the Obama administration in the United States, talking about 30 year and 50 year timelines of a plan that they might have of reducing emissions, you know, 3 percent per year, for example, up until 2050, or trying to reduce emissions by 30 percent by 2050. We simply do not have anywhere near that kind of time.
WORONCZUK: And, Peter, what's your take? Do you think that we've already passed the point of no return in terms of controlling polar ice cap melting?
WADHAMS: Yes, I think we have. A few years ago, I predicted that the summer sea ice--that's the September minimum--would go to zero by about 2015. And at that stage, it was only really one model that agreed with me. My prediction was based on observations from satellites and from measurements from submarines of ice thickness, which I've been doing from British subs, and Americans have been doing the same from American subs. And the trend was so clear and so definite that it would go to zero by 2015 that I felt it was safe to make that prediction, and I still think it is, because next year, although this year we don't expect things to retreat much further than last, next year will be an El Niño year, which is a warmer year, and I think it will go to zero.
And once it goes to zero in the summer, it is sort of irreversible, because it means that the next summer there'll be a longer ice-free period. Instead of just one month, there might be two or three months, because the water warms up during the summer months. If there is no ice there, it's absorbing solar radiation, the water's warming up.
As we've heard, one of the things that would happen from that is that the water on the continental shelves warms very much. We've seen seven degree temperatures from satellites. And that means that the seabed permafrost near the coast then melts, and that releases methane. And the methane effect, I think, is the biggest of all the threats from the retreat of sea ice. We've got other effects as well. The retreat is causing warmer air over Greenland, which is causing the Greenland ice cap to melt faster and sea level rise to accelerate.
But the biggest immediate threat, I think, is that the warming of the water in summer is causing methane to be released from the seabed because of the melt of offshore permafrost. And this is something that's being documented by a Russian-American group, and for several years. And we're joining them with some European funding, which we're putting in to help fund their work and going out with them.
So I think that the documentation of this and the fact that the extra methane we see each summer--that's the big, increasing amounts of methane plumes in the Arctic reaching the surface, releasing methane into the atmosphere--and that's reflected in NASA's measurements from satellites of methane levels in the atmosphere in the northern hemisphere, which have started to go up again quite fast after having been flat for a decade or so. I think that that is a big threat.
But the loss of the sea ice is something that's, I think, irreversible, because all the trends are towards decreased sea ice extent, and there's no countervailing trend that will bring the ice back. The biggest effect is an albedo feedback effect, for instance, the fact that as the ice disappears, you're replacing highly reflective ice and snow with poorly reflective water. And that has an effect of increasing the rate of warming of the Arctic, and that increases the rate of retreat of the ice. So all the feedbacks are positive. There's no negative feedbacks that will tend to bring the ice back. Once it's gone in summer, it's gone, and I think the summer ice-free season, having started very soon, maybe next year, will then extend itself so that we might have a number of months of ice-free conditions. We'll have plenty of ice in the winter, of course.
But that ice-free summer will have all these knock-on effects of increasing methane release, maybe producing a catastrophic pulse of methane, which has been predicted based on how much methane is sitting in the form of methane hydrates. And that pulse would be very catastrophic. We examined this with climate modeling and economic modeling and found that a pulse of the size that's predicted based on how much methane is there could cause a temperature rise of 0.6 of a degree within 20 years. Now, that's a big addition to the amount of warming that is already going on. It's pretty much doubling the rate of global warming.
And so--plus it's costing some astronomical amount of money as well to the planet. This is using a model, an economic model. So the cost to the planet of having this happening far exceeds any of the benefits we might get from Arctic oil or shipping through the Northwest passage. We're really stuck with a massive economic cost and, of course, a catastrophic cost to the planet.
So all these things are bound to happen, sadly. And the only way in which they wouldn't happen would be if for some surprising reason the methane hydrates on the seabeds stopped emitting methane. But then we wouldn't get off scot-free, because the other source of increased methane is permafrost on land, and that's also melting as the climate warms. And it's a slower process, but in the end there's more methane going to be released from that over many decades than would be released from a pulse in the Arctic Ocean. So in the end we'll have the methane impact on global warming, which hasn't been taking account of IPCC [models]. It's going to come in and it's either going to hit us fast or it's going to get us slowly, but it's going to hit us.
WORONCZUK: Okay. Peter Wadhams of the University of Cambridge, thank you for joining us.
WADHAMS: Pleasure.
WORONCZUK: And Dahr Jamail from truth out, thank you for joining us.
JAMAIL: Thank you.
WORONCZUK: And thank you for joining us on The Real News Network.

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