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Transcript
Dr Wieslaw Maslowski predicted a 2013 Ice Free Summer Arctic five years ago - now he says that may have been too conservative
Posted on 24 Mar 2008
We speak to Wieslaw Maslowski about his prediction that by the summer of 2013, we will have completely lost ice cover in the Arctic. Dr. Maslowski says that the complete loss of summer ice may actually happen sooner. The concern we have at Beyond Zero Emissions is that without moving to near zero emissions and drawing down atmospheric carbon as soon as possible, this could cause the irreversible melt of Greenland leading to 5 metre sea level rises this century.
Wieslaw Maslowski podcast
Matthew Wright: On the phone we have Wieslaw Maslowski from the US Postgraduate Naval School. Good morning Dr Maslowski? We're speaking to you today about the situation with the Arctic ice. As our listeners are aware, that's a very serious situation and ah, well ahead of estimates by scientists some years ago, and by science thats led to summaries and the IPCC stuff, we're seeing by 2020 or, there's a quote from Wieslaw that perhaps 2013 is even a possibility for the loss of the complete summer ice extent.
Now a little bit about Dr Maslowski. He's got a PhD from the University of Alaska in 1994. He's in charge of a group that looks after a particular model that simulates arctic ice and I think it has 9km resolution - but that's over a very large area. In the past, he's worked in research areas in arctic oceanography, numerical ocean and sea ice modeling, ocean general circulation and climate change. In 2001 to the present, he's been research associate professor at the Department of Oceanography. 1995 to 2001, he was the research assistant professor, Department of Oceanography conducting reimbursable research, supporting student thesis research and teaching script oceanography. So good morning Wieslaw.
Dr Wieslaw Maslowski: Good morning, thank you for having me.
Matthew Wright: No problem and thank you for joining us. Just tell us a little bit about your research work around modeling of the Arctic ice.
Dr Wieslaw Maslowski: Well, I guess just trying to introduce in a very short time, I guess, what we've been doing for some last two decades or so. We're using mathematical models that are formulated in numerical programs using some programs that we're using Fortran programming language, so the computers can understand those programs. We're using those programs that are describing the mathematical equations of the behaviour of the ocean and the sea ice and than we're actually prescribing to those models realistic atmospheric forcing as has been observed from satellites and from various stations all over the world and trying to eventually understand the past and the present conditions that have occurred in the Arctic ocean, and by trying to understand that maybe trying to have a better view and a picture what's expected to come in the future.
Matthew Wright: So, just tell me about the US Naval Postgraduate School. Is the funding for any sort of military purposes or is it just a general research?
Dr Wieslaw Maslowski: Well, the Naval Postgraduate School it's, ah, you could probably describe in summary. This is kind of like the only navy university in the United States. We offer only graduate degrees, meaning Masters degrees and PhDs. There is a separate academy, naval academy, in Annapolis where they actually, the navy officers and other military officers have a chance to pursue their Bachelor - undergraduate degree. So, at this institution here in Monterey California, we have graduate students and there is a mix of faculty. The institution primarily is to eventually educate the navy and other military personnel towards higher degree education, specialising in technical and defence areas such as oceanography, meteorology, space engineering and then we have departments of national security and business administration and so on. We have international study departments. So this is, kind of like, specific to the military and specifically to navy needs - a higher education institution equivalent to a university in the United States.
Matthew Wright:That's very interesting. So, in terms of what you've been reporting, what's happening in the arctic, our understanding is that the Arctic ice shrank between 2005 and 2007 by a bit over 22% and to put that into context for our listeners, it was over 1 million square kilometres - about the size of the Northern Territory in Australia. So, if you can think of that huge land mass in the Northern Territory, that was the area.
And also, our understanding is that when the Arctic ice extent is fully covered then light coming in from space hits the ice and 80% of that reflects back into the atmosphere, so it doesn't convert into heat inside the Earth's greenhouse or inside the Earth's atmosphere. So, just correct me if I'm wrong here, just one more thing that's of interest there, is that once the ice melts away, 90% of the light coming in through the atmosphere actually converts to heat inside the atmosphere and heats the ocean. Is that correct?
Dr Wieslaw Maslowski: Well, there are several issues that you brought up which are quite important for me to clarify and you tried to describe them quite correctly, I guess. The first thing is that the observations of the ice extent - you can think about actually flying a plane or a high altitude instrument on satellites and trying to determine basically where the white is and where they have black - being the ocean surface without ice cover. And those observations have been very, ah, quite good quality since late 1970s, with the introduction of the microwave satellites, such as EurS1 and EurS2 in Europe, and several others satellites, ssmi satellites in the United States.
So, we have from observations, this is not my studies in particular, this is the US and European and other space agency programs that allow us to have a picture or view in time of the evolution of the changes of the ocean and sea ice surface, including polar regions, not only in the northern hemisphere but also in the southern hemisphere as well. The same satellites are quite accurately observing and providing information of the Southern Ocean and the Antarctic ice sheets. So, those observations are not actually particular results of our study. What we're trying to do is eventually use these observations as data to feed into the models that we're using and people are using and on top of this also, those observations are very useful for validating model results that people like our group or other groups are doing. And in order to understand the interactions and feedbacks between ocean ice and atmosphere and various other components of the climate system in a particular region, one needs to have some ways of at least convincing himself or herself and other people that at least where some areas were observations are available, the skill of such models is pretty reasonable.
So, what we do with the ocean and ice simulations which prescribe realistic atmospheric forcing, we're trying to validate the models with the valid observations from satellites and in situ, field observations. And then eventually look at parameters that are not readily available from observations to fill out the gaps of the missing information and probably synthesize this information together with observations to eventually come up with a bigger picture evolving in time and space.
So what we're doing, we're actually simulating the sea ice and ocean and interaction with the atmosphere and the satellites are very good instruments providing aerial observations of the arctic sea ice which is, as I mentioned, it's basically the satellite sea where the ice is; being a lot of reflectivity from the ice surface due to a parameter called ice albedo or surface albedo, which is simply a ratio of what the incoming solar radiation versus what the reflected solar radiation. So, reflectivity or ice albedo is high where you have sea ice and the surface is white. For the ocean, the surface is really dark and the reflectivity goes down, meaning that most of the solar radiation is absorbed by the ocean and not reflected back to the atmosphere. The consequences of this are several but I'm not sure if we have time to eventually go into details describing all the possible consequences of the changing surface albedo and the surface cover in the Arctic.
Matthew Wright: We do have another 15 minutes left in the show so we can get into some depth there. But just for listeners, when the sea ice cover is lost - and we're talking about 5 million square kms, what the average was - for say 1979 to 2002. Is that about right?
Dr Wieslaw Maslowski: I believe it was close to 7 million.
Matthew Wright: Oh, 7 million square km. And in Australia, we have a rough benchmark; we say that for every square metre, a thousand Watts (W). So that's like ten 100W light globes every hour - 1000W - of energy that actually hits the surface of the land. Is that a similar situation in the Arctic? Or with the sun in the Arctic, is there a lot of cloud cover and that, sort of, balances it out? It's a lot of energy.
Dr Wieslaw Maslowski: There is a lot more cloud cover so it's not direct radiation, you know, it's more dispersed solar radiation but it's very important. I would prefer not to put a number, because actually I'm not an atmospheric scientist so I'm not actually feeling comfortable to talk about the solar radiation effect in the atmosphere. But the point is that its the primary forcing coming from the sun and the atmosphere, in terms of wind. So those two parameters, those two particular forcing parameters, have been quite extensively looked into, their effect on the Arctic sea ice and the recent changes in the Arctic sea ice.
What our group, at the Naval Postgraduate School here, brings a new perspective to this table, to this understanding, is that we argue that we also have to consider the effect coming from the ocean. And the effect from the ocean is actually; you already mentioned that by removing sea ice, the ocean absorbs much more energy from the sun than the sea ice has very high reflectivity so it's not only that we observe more solar radiation but also that the solar radiation hits the top surface of the ocean, which then eventually; the heat surface ocean, the top or upper part of the ocean becomes available in the longer term for effecting the ice from underneath, simply melting it. So, our contribution to this overall studies of the Arctic sea ice decrease is that we are arguing that the oceanic forcing indirectly receiving heat and the momentum, or the motion, from the atmosphere actually pretty much changes the time and space scale exchanges and interactions and ice response and then eventually provides, pretty much, a separate forcing to the sea ice condition.
Matthew Wright: Ok. So now, it was reported in The New York Times that you said that 2013 was a possibility, and perhaps you'd actually projected this some years ago, that we could lose the summer sea ice extent - that's in the summer solstice is it?
Dr Wieslaw Maslowski: That is correct. So the minimum in the Arctic ice extent has been typically occurring some time in September, between early September and late September every summer. So, the minimum of ice extent is simply defined as the ice edge of percentage roughly say between 15, maybe at 20%, ice cover. And then everything inside this ice edge position on the Atlantic side and on the Pacific side is considered to be the ice extent so it's not really concentration - it's just the area within the 15% or 20% ice concentration or more. And this ice minimum has been declining quite significantly. The global climate models have predicted, and your audience is probably familiar with this International Panel for Climate Change study, Annual Report IV that has been published and presented quite extensively this year, earlier this year in 2007, and actually the panel together with 'president' Al Gore have won the Nobel Prize nomination, so those studies from this panel, the multi-national climate simulation study have predicted the ice might be disappearing in summer, the northern summer in the Arctic, maybe sometime by the end of this 21st century.
There are some model simulations, single model simulations, that are suggesting that it could possibly occur as early as 2050 or maybe even as early as 2030. Comparing those models simulations predictions with the satellite observations of the Arctic sea ice extent actually shows that most of those models are too conservative predicting the current and the past ice extent changes in the Arctic as has been observed. So the idea is that the climate models - they're underestimating, they are too conservative in their prediction.
What our contribution, our study contribution to this overall topic is that we're saying that the satellite are only observing the 2-dimensional changes in the sea ice in the Arctic in terms of this ice extent. However, we do not have the observations of ice thickness - the third dimension, the vertical dimension - are very limited of the Arctic sea ice. And having those models that we used, we are able to look at the changes associated, not only with the ice extent, but also ice thickness and this way we can eventually calculate and try to understand the changes in the total ice volume in the Arctic. And our studies are suggesting that actually the volume and the thickness is decreasing even faster than the aerial observations from satellites. And this way we're saying that actually if we already have lost probably about 40% volume in the Arctic so far, if we project this trend ongoing for the last 10 - 15 years, we probably will reach zero in summer some time mid next century, mid next decade, I'm sorry.
Matthew Wright: So, there's been other projections from some glaciologists around 2020. So, somewhere in that range. You said 2013 in The New York Times where it was reported, but something between then and 2020 is very in the ballpark and a likelihood.
Dr Wieslaw Maslowski: It's interesting that the longer we wait and the more we see what is happening, what changes are happening in the Arctic, the sooner people start predicting those changes to completely melted ice in summer in the Arctic - as soon as in the next decade or so.
Matthew Wright: I think there's a lot of, there's inertia that's lacking because, I think there's some conservatism and a lot of scientists are a bit afraid of being seen to be alarmist or something like tha, so it's now that the observed is there on record that suddenly everyone who's got a prediction seems to be coming out now or perhaps it is that the media are just getting interested.
Dr Wieslaw Maslowski: I think the media is definitely getting much more interested and the society is trying to understand what is happening out there, not only in the Arctic but also the ice shelf around Antarctica and so forth. So, definitely the interest and demand for information is much higher than couple years ago. My statement you quoted and was printed in The New York Times of 2013, my first presentation where I actually had this projection stated exclusively was about 4 or 5 years ago in San Francisco, at American Geophysical Union poll meeting. So, I'm not actually upgrading my projection, I'm just saying that it may happen sooner but we were one of the early people who were saying that it might happen within the next decade, instead of by the end of this century.
Matthew Wright: That's definitely of concern because in Australia of course fortunately, and I'm sure you think that this is a good thing, our country's decided now to ratify the Kyoto Protocol with the change of government and currently in Bali they're now starting to talk about - nothing like what we believe needs to occur, and that's to take all our industrial emissions down to near zero emissions and then start actively drawing down atmospheric carbon using, getting char and carbon into soils. But, I think it's really good to see that Indonesia and China are calling for 25 - 40% cuts in CO2.
What do you think need to happen in order to, sort of, preserve the ice extent? I think James Hansen from NASA has suggested that, that might be one of the main, sort of, triggers or the main tipping points and that maintaining that summer ice extent might be very important for keeping a rather stable sort of climate that supports many of the ecosystems and many of the people that are living on Earth who are dependent on them.
Dr Wieslaw Maslowski: Well, personally I have my own perspective on all the carbon emission and global warming. However, I wanted to make very clear that the tools that we have used so far for our studies are not involving or allowing us to discriminate between greenhouse gases effect or other climate variability. So, what we see is what we see but there is no direct cause, there is no possibility for us to link direct cause of ice melt to something like greenhouse gases. My personal perspective is that we definitely should be cutting on the emission rates worldwide and it may not stop whatever the changes that are happening right now but we are still not very certain what kind of changes we can expect not only within the next 10 years but within 20 - 50 years into the future. So, if we sit and do nothing then definitely it will be much worse than if we try to actually reduce our pollution and emissions of carbon dioxide into the atmosphere for the long term.
Matthew Wright: Another area that's sort of gets in, sort of visualises it for our listeners, and I will just say that listeners are tuned into 855AM 3CR and you're listening to the Beyond Zero show and we're talking to Wieslaw Maslowski.
For listeners, we just suggested that an area the size of the Northern Territory potentially could be going from a mirror that reflects 80% of the light back into space; or there's some variability there in the amount of light because of cloud cover and things like that but it's still a large area, a very large area. And listeners in Australia know how big the Northern Territory is. If that then extends to the whole of the Arctic, I think ice extent, and you said at one stage, it was 7 million square kms, well that's pretty much the size of Australia. So, some sort of a mirror with some level of reflectivity the size of Australia, that's certainly a large albedo effect. So, tell us about that again but also about the ice thickness and what you've seen there because I think it's gone from 5 metres to 2 metres in many places?
Dr Wieslaw Maslowski: The average ice thickness observed from satellites, and more accurately from the submarines that carry instruments called upper looking sonars, something like video camera that's looking up from the submarine below, looking underneath the sea ice. And the typical ice thickness in the Arctic, central basin in the Arctic, was on average about 3 to 4 metres for the last decade. What we have seen in the last decade, this thickness has on average decreased to below 2 metres, roughly 35 to 40% probably. If we would have most recent observations of the summer of 2007 I would argue that we probably lost more than 40% by now, by the summer of 2007. So, the ice thickness is declining even faster than what we have observed and detected using satellites and in terms of the ice extent in the Arctic Ocean.
As far as the changes in the albedo and changing the mirror into the totally observing ocean surface, there's 2 aspects of that I would like to bring to the audience there and your attention as well. One aspect actually is that if you have warmer water, the volume will actually expand a little bit and I just recently listened to several presentations by sea level people, scientists who study sea level for the past and the future, and apparently in the order of 50% of the current sea level increase can be accredited to the changes in the ocean surface temperature, not necessarily the addition of new volume of water. So, if we increase the temperature in the Arctic we might see some increases in the sea level due to simply increasing the temperature. The sea ice melting is not going to introduce new volume because it's already floating in the ocean. So, the volume of ice is already accounted in terms of the sea level, but the change of the sea level due to the increase temperature, from freezing temperatures of water of -2 Centigrade, if we go to zero or above zero Centigrade the ocean is going to expand at least a bit.
The other aspect of the no ice in summer in the Arctic is actually its potential effect on melting the Greenland glaciers flowing into the oceans. We already have seen, and I've listened to several people's presentations where they discuss the potential effect of warmer surface water entering glaciers and melting the ice flowing out into the glaciers from Greenland, might be actually accelerating the flow from the central Greenland towards the coast. So, those two aspects that this change in the ice cover in the Arctic might have immediate effect on.
Matthew Wright: We're going to have to wrap it up now. But that was actually my last question. It was, you know, bringing all that warm water to the Arctic, is that likely to affect that mobility we're getting in the Greenland ice sheets? And I think you've answered that. That's a big concern.
Dr Wieslaw Maslowski: That is correct. However, there are other people, other experts, that can probably address this issue more accurately than I did.
Matthew Wright: And we hope to get Dr. James Hansen from NASA on to perhaps speak about that, or some glaciologists. Great, thank you very much for joining us.
Dr Wieslaw Maslowski: Your welcome and thank you for having me again.
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