Winter warming in West Antarctica caused by central tropical Pacific warming by Q. Ding, E.J. Steig, D.V. Battisti & M. Küttel, Nature Geoscience (April 10, 2011)

Nature Geoscience (April 10, 2011); doi:10.1038/ngeo1129

Winter warming in West Antarctica caused by central tropical Pacific warming

• Qinghua Ding,
• Eric J. Steig,
• David S. Battisti and
•  Marcel Küttel

Abstract

The Pacific sector of Antarctica, including both the Antarctic Peninsula and continental West Antarctica, has experienced substantial warming in the past 30 years. An increase in the circumpolar westerlies, owing in part to the decline in stratospheric ozone concentrations since the late 1970s, may account for warming trends in the peninsula region in austral summer and autumn. The more widespread warming in continental West Antarctica (Ellsworth Land and Marie Byrd Land) occurs primarily in austral winter and spring, and remains unexplained. Here we use observations of Antarctic surface temperature and global sea surface temperature, and atmospheric circulation data to show that recent warming in continental West Antarctica is linked to sea surface temperature changes in the tropical Pacific. Over the past 30 years, anomalous sea surface temperatures in the central tropical Pacific have generated an atmospheric Rossby wave response that influences atmospheric circulation over the Amundsen Sea, causing increased advection of warm air to the Antarctic continent. General circulation model experiments show that the central tropical Pacific is a critical region for producing the observed high latitude response. We conclude that, by affecting the atmospheric circulation at high southern latitudes, increasing tropical sea surface temperatures may account for West Antarctic warming through most of the twentieth century.

Figures at a glance

left

1. 

2. 

3. 

4. 

right

http://www.nature.com/ngeo/journal/vaop/ncurrent/abs/ngeo1129.html

Eric Steig: West Antarctica: still warming. The temperature reconstruction of O’Donnell et al. (2010) confirms that West Antarctica is warming — but underestimates the rate

West Antarctica: still warming

The temperature reconstruction of O’Donnell et al. (2010) confirms that West Antarctica is warming — but underestimates the rate

by Eric Steig, RealClimate, February 1, 2011

At the end of my post last month on the history of Antarctic science I noted that I had an initial, generally favorable opinion of the paper by O’Donnell et al. in the Journal of Climate. O’Donnell et al. is the peer-reviewed outcome of a series of blog posts started two years ago, mostly aimed at criticizing the 2009 paper in Nature, of which I was the lead author. As one would expect of a peer-reviewed paper, those obviously unsupportable claims found in the original blog posts are absent, and in my view O’Donnell et al. is a perfectly acceptable addition to the literature. O’Donnell et al. suggest several improvements to the methodology we used, most of which I agree with in principle. Unfortunately, their actual implementation by O’Donnell et al. leaves something to be desired, and yield a result that is in disagreement with independent evidence for the magnitude of warming, at least in West Antarctica.

In this post, I’ll summarize the key 

methodological changes suggested by O’Donnell et al., discuss how their results compare with our results, and the implications for our understanding of recent Antarctic climate change. I’ll then try to make sense of how O’Donnell et al. have apparently wound up with an erroneous result.
More »

Eric Steig: O’Donnellgate. Or…Some thoughts on Personal Responsibility and the Peer Review Process

O’Donnellgate

or…Some thoughts on Personal Responsibility and the Peer Review Process

by Eric Steig, RealClimate, February 9, 2011

Ryan O’Donnell made a series of serious of allegations against me at ClimateAudit, in the context of our friendly dispute about whether his new paper in the Journal of Climate supports or ‘refutes’ my own results, published in Nature.

To his credit, Ryan has offered to retract these allegations, now that he is a little better acquainted with the facts. However, it is still important, I think, to set the record straight from my point of view. There were such a great number of claims about my “dishonesty,” “duplicity” and [implied] stupidity, all of which are untrue, that it really isn’t worth trying to respond in any detail. Just responding to the main two ought to suffice to make the point.

“Eric recommends that we replace our TTLS results with the ridge regression ones (which required a major rewrite of both the paper and the SI) and then agrees with us that the iRidge results are likely to be better . . . and promptly attempts to turn his own recommendation against us.” 

“[in his RealClimate post]…he tries to … misrepresent the Mann article to support his claim [about the iridge routine] when he already knew otherwise. How do I know he knew otherwise? Because I told him so in the review response.”

While it is quite possible that O’Donnell believes both of these claims, they are both false, as it is rather easy to demonstrate.

First, I never suggested to the authors that they use ‘iridge.’ This was an innovation of O’Donnell and his co-authors, and I merely stated that it ‘seems’ reasonable. As O’Donnell’s co-authors are fond of pointing out, I am not a statistician, and I did not try to argue with them on this point. I did, however, note that previously published work had shown this method to be problematic:

“The use of the ‘iridge’ procedure makes sense to me, and I suspect it really does give the best results. But O’Donnell et al. do not address the issue with this procedure raised by Mann et al., 2008, which Steig et al. cite as being the reason for using ttls in the regem algorithm. The reason given in Mann et al., is not computational efficiency — as O’Donnell et al state — but rather a bias that results when extrapolating (‘reconstruction’) rather than infilling is done.

Second, I was the reviewer of the first three drafts of O’Donnell et al submission. However, I did not the review draft four, which was the published one. , and which is markedly different from draft 3[note correction: it has been pointed out that it's not really very different; in other words, my criticisms of draft 3 were ignored]. Nor was I ever shown their response to my comments on draft 3, so I did not in fact ‘already know’ what O’Donnell claims I did. It appears that the editor was swayed by the arguments that I was not a helpful reviewer. In other words, even if one believes that I was “bullying” them into showing particular results, they still had the last word (as any author should).

The fact of the matter is that my reviews of O’Donnell’s paper were on balance quite positive. I wrote in the confidential comments to the editor in my very first review that

I emphasize that I think that a fundamentally reworked version of this manuscript could potentially provide a useful scientific contribution, and many of the points made do indeed have scientific merit. Indeed, the authors have done a very thorough analysis, and are to be congratulated on this.

In my second review, I wrote that “O’Donnell et al. have substantially improved their manuscript … and clarified a series of items that led to some confusion on my part.”

With respect to O’Donnell’s lengthy discussion of the technical aspects of the difference between our papers, I’m not complaining. It is possible to have a disagreement — or even to be wrong — about the technical aspects of a paper without being ‘duplicitous’. The dependence of any analysis on the technical aspects of the methodology are completely legitimate subjects of discussion, and it is important to be clear about what does and what does not depend on those choices. People who want to see what the data are saying about the real world will focus on the similarities, people who are focussed on proving people wrong will focus on the differences. This is how O’Donnell and I can (legitimately) disagree about what their results mean.

The reality is that editors, not reviewers, make decisions about what is acceptable and what is not. Any comments I made as a reviewer of O’Donnell et al.’s work would have been weighed against what other reviewers said (and obviously were, since the main criticism I had of the paper was not ever addressed), not to mention the responses of the authors themselves. And the decision about what content eventually winds up published is still ultimately up to the authors. If the authors feel that they are being bullied into presenting their results in a particular way (as is the allegation here), then they have the choice to withdraw the paper and submit it elsewhere, or complain to the editor. But once they have signed off on the paper, it is their paper, and blaming someone else — reviewer or editor — for its content is simply passing the buck.

It’s perhaps also worth pointing out that the *main* criticism I had of O’Donnell’s paper was never addressed. If you’re interested in this detail, it has to do with the choice of the parameter ‘k_gnd’, which I wrote about in my last post. In my very first review, I pointed out that as shown in their Table S3, using k_gnd = 7,

“results in estimates of the missing data in West Antarctica stations that is further from climatology (which would result, for example, from an artificial negative trend) than using lower values of k_gnd.”

Mysteriously, this table is now absent in the final paper (which I was not given a chance to review).

Some months ago, O’Donnell cordially (though quite inappropriately) asked me if I was one of the reviewers, and also promised not to reveal it publicly if I didn’t want him to. I told him I was, but that I would prefer this not be public since the ‘opportunity for abuse’ was simply too great. Talk about prescience!

Many of my colleagues have warned me many times not to trust the good intentions of O’Donnell, Condon, and McIntyre. I have ignored them, evidently to my peril. But you know what has given me the most pause? The fact that a number of my colleagues and many otherwise intelligent-seeming people still seem to treat these guys as legitimate, honest commenters, whose words have equal weight with, say, those of Susan Solomon or J. Michael Wallace, or, for that matter, Gavin Schmidt or Mike Mann or myself. As a reporter wrote to me today “it’s simply impossible for a lay observer to make a judgement on his/her own.” Really?!

Perhaps there is a silver lining here. Perhaps the utter silliness of the shrill accusations that O’Donnell made against me — based on a version of the facts, in his head, that are demonstrably and unequivocally false, coupled with the fact that he then retracted them (or at least has promised to do so), will help more people see what the steadily growing list of other scientists who’ve been accused by McIntyre and his associates of plagiarism, dishonesty, data manipulation, fraud, deceit, and duplicity have been telling me for years: 

these people are willing to say anything, regardless of the cost to others’ reputations and to the progress of legitimate science, to advance their paranoid worldview.

I’ve even got a name for the clarity this affair would seem to offer: O’Donnellgate.

Sadly, attacking climate scientists by mis-quoting and mis-representing private correspondences or confidential materials appears now to be the primary modus operandi of climate change deniers. To those that still don’t get this — and who continue to believe that these people can be trusted to present their scientific results honestly, and who continue to speculate that their may be truth in the allegations made over the years against Mike Mann, Ben Santer, Phil Jones, Stephen Schneider, Andrew Weaver, Kevin Trenberth, Keith Briffa, Gavin Schmidt, Darrell Kaufmann, and many many others, just because they ‘read it on a blog somewhere’ — I’d be happy to share with you some of the more, err, ‘colorful,’ emails I’ve gotten from O’Donnell and his coauthors.

If you still don’t get it, then I have a suggestion for a classic short story you should read. It’s called,The Lottery, by Shirley Jackson.

http://www.realclimate.org/index.php/archives/2011/02/odonnellgate/

Eric Steig & Ray Pierrehumbert: The Starship vs. Spaceship Earth (or why Freeman Dyson went emeritus)

The Starship vs. Spaceship Earth

by Eric Steig and Ray Pierrehumbert, RealClimate, February 7, 2011

One of my (Eric’s) favorite old books is The Starship and the Canoe by Kenneth Brower It’s a 1970s book about a father (Freeman Dyson, theoretical physicist living in Princeton) and son (George Dyson, hippy kayaker living 90 ft up in a fir tree in British Columbia) that couldn’t be more different, yet are strikingly similar in their originality and brilliance. I started out my career heading into astrophysics, and I’m also an avid sea kayaker and I grew up with the B.C. rainforest out my back door. So I think I have a sense of what drives these guys. Yet I’ve never understood how Freeman Dyson became such a climate contrarian and advocate for off-the-wall biogeoengineering solutions like carbon-eating trees, something we’ve written about before.

It turns out that Brower has wondered the same thing, and in a recent article in The Atlantic, he speculates on the answer. “How could someone as smart as Freeman Dyson,” writes Brower, “be so wrong about climate change and other environmental concerns..?”

Brower goes through a number of possible explanations for the Dyson paradox, some easily dismissed (senility; he’s a theoretician with no sense of practicality) some not so easily dismissed (he’s only joking, don’t take it seriously, he doesn’t take it all that seriously himself). But in the end, for Brower, it seems to come down to two conspiring things about Dyson. The first is that Dyson has an abiding faith in the ability of technology to do anything we want it to. It’s not surprising, then, that Dyson thinks we can ‘fix climate’ as well. That, in itself, makes Dyson not so much a “global warming skeptic” as an extreme techno-optimist. In fact, even leaving technology aside, he has a touching faith that whatever humans may do to the environment, it usually turns out for the best. In this essay, he writes:

“The natural ecology of England was uninterrupted and rather boring forest. Humans replaced the forest with an artificial landscape of grassland and moorland, fields and farms, with a much richer variety of plant and animal species. Quite recently, only about a thousand years ago, we introduced rabbits, a non-native species which had a profound effect on the ecology. Rabbits opened glades in the forest where flowering plants now flourish.”

We daresay that the Australians have a somewhat less benign view of rabbits (as the New Zealanders do of possums). And that maybe Dyson has a thing or two to learn about the biodiversity of unmanaged ecosystems.

Second, Dyson’s obsession has always been the stars, not the earth: he spent many years working on the design of a spaceship (hence the title of Brower’s 30-year old book) that would take him there. It’s not so much that he doesn’t care about our home planet — he must have learned something about ‘spaceship earth’ from son George over the years. Rather, he is simply very confident that we can always get off if we have to. “What the secular faith of Dysonism offers,” Brower writes” is, first, a hypertrophied version of the technological fix, and second, the fantasy that, should the fix fail, we have someplace else to go.” Dyson has stated in many places, and in various ways, that he thinks global warming is not a big problem, and that its importance has been exaggerated. To put things in perspective, though, Dyson doesn’t particularly think that the extirpation of all life other than human would be a particularly big deal “We are moving rapidly into the post-Darwinian era, when species other than our own will no longer exist, and the rules of Open Source sharing will be extended from the exchange of software to the exchange of genes,” he is quoted as saying in Brower’s article. Dyson’s idea of what constitutes a “big problem” may be, well, just a bit different from what most of the rest of us might have in mind.

Brower’s conclusions sound right on the mark to us, but don’t fully explain Dyson. Perhaps Brower is being gentle, since he is an old friend, or perhaps he simply isn’t aware of it, but one issue he does not touch on in his article is is how deceptive (apparently deliberately) Dyson can be.

The problem is that Dyson says demonstrably wrong things about global warming, and doesn’t seem to care so long as they support his notion of human destiny. Brower reports that Dyson doesn’t consider himself an expert on climate change, has no interest in arguing the details with experts, and yet somehow knows that the experts don’t have any answers worth listening to. That doesn’t stop Dyson from making sweeping pronouncements, many of them so egregiously wrong that it would hardly have taken an expert to set him straight.

The examples of this are legion. In the essay “Heretical thoughts about science and society” (excerpted here) Dyson says that CO₂ only acts to make cold places (like the arctic) warmer and doesn’t make hot places hotter, because only cold places are dry enough for CO₂ to compete with water vapor opacity. But in jumping to this conclusion, he has neglected to take into account that even in the hot tropics, the air aloft is cold and dry, so CO₂ nonetheless exerts a potent warming effect there. Dyson has fallen into the same saturation fallacy that bedeviled Ångström a century earlier.

And then there are those carbon-eating trees. He likes this one so much he put it in both theHeresy essay and in his piece in NY Review of Books. He points out that the annual fossil fuel emissions of carbon correspond to a hundredth of an inch of extra biomass per year over half the Earth’s surface, and suggests that it shouldn’t be hard to tweak the biosphere in such a way as to sequester all the fossil fuel carbon we want to in this way. Dyson could well ask himself why we don’t have kilometers-thick layers of organic carbon right now at the surface, resulting from a few billion years of outgassing of volcanic CO₂. The answer is that bacteria have had about two billion years to evolve so as to get very, very good at combining any available organic carbon with oxygen. It is in fact extremely hard to put organic carbon in a form or place where it doesn’t get oxidized back into CO₂ (Mother Nature thought she had done that trick with fossil fuels but we sure fooled her!) And if you did somehow coopt ten to twenty percent of the worldwide biosphere’s photosynthetic capacity to take up carbon and turn it into a form that couldn’t rot ever, you’d have to sort of worry about how nutrients would ever get back into the ecosystem. And also maybe whether the carbon-eating trees might get out of control and suck out so much CO₂ you wound up in a Snowball Earth.

Dyson espouses a generic disdain for climate models and climate modellers: ” Here I am opposing the holy brotherhood of climate model experts and the crowd of deluded citizens who believe the numbers predicted by the computer models.” Like most of us, he has little confidence in the modelling of clouds. But with great ignorance of the nature of the modelling enterprise, he declares: “It is much easier for a scientist to sit in an air-conditioned building and run computer models, than to put on winter clothes and measure what is really happening outside in the swamps and the clouds” Actually, those of us who go to Antarctica to drill ice cores certainly put on winter clothes, and paleoclimatologists are out in the swamps and ocean muck all the time. And there are plenty of scientists flying around in the clouds, trying to gauge their effects. The mainstream estimate that the climate sensitivity is around 3°C for a doubling of CO₂ does not simply comes from computer models. Study of the Last Glacial Maximum, the Pliocene and the Paleocene-Eocene Thermal Maximum all rule out the idea that there is a strongly stabilizing cloud feedback. Ahe fact that we cannot precisely quantify cloud feedbacks also means that there is a lot of risk, that cloud feedbacks could make a doubled-CO₂ world much hotter, not much cooler. Dyson’s writings conveniently ignore this two-directional implication of uncertainty, and they they also ignore the implications of the long atmospheric lifetime of CO₂, which means if we wait and see how hot it gets and find we don’t like it, there’s nothing much to be done (unless, of course, we can simply go somewhere else).

Finally, there is the familiar examples of Dyson attacking the style of the debate, rather than its substance. Reporting on written debate between Richard Lindzen and Stefan Rahmstorf, in theNew York Review of Books 
New York Times book review
, Dyson juxtaposes Lindzen’s claim that “observations suggest that the sensitivity of the real climate is much less than that found in computer models” with Stefan calling this “simply ludicrous”. Dyson gives the impression that rational arguments from skeptics are met with “open contempt” by the majority. But he fails to mention that Stefan showed in detail why Lindzen’s claim is wrong: Lindzen ignored ocean thermal inertia when comparing observed warming with the equilibrium climate sensitivity. Any physicist should be able to judge that Stefan is right and Lindzen is wrong on this point. He also failed to mention that Stefan used the word “ludicrous” only in a “personal postscript” to a completely sober scientific article, referring to Lindzen’s claims that a vast conspiracy of thousands of climatologists worldwide is misleading the public for personal gain. Dyson’s account of the Lindzen-Rahmstorf exchange neither fairly covers the substance of the argument, nor is it a fair portrayal of its style – Dyson seems to have twisted it as much as he could to score a political point.

In the Heresy essay, Dyson repeatedly gives himself a way out by claiming he is only tossing out ideas that should be thought about; he at times emphasizes that he does not know the answers, only the questions that should be raised. However, that does not stop him from making confident claims that he has a broader view than others, as in this interview with Mike Lemonick, and somehow Dyson never gets around to thinking about what the consequences are if we continue inaction on CO₂ emissions and he turns out to be wrong. More importantly, all of the things Dyson argues “heretically” should be looked at — e.g. land carbon sequestration or the lessons from the Altithermal period around 8000 years ago — are in fact already being intensively investigated and are not turning up any silver bullets to allay concern about climate change. When push comes to shove, Dyson is really only offering warmed-over standard contrarian talking points. Heresy, or more broadly an outsider’s viewpoint, can be a good thing when it shakes loose new ideas. But surely, we have a right to expect a more original form of heresy from the architect of Dyson spheres and nuclear starships.

In short, it’s not so simple as the ‘self delusion’ Brower talks about. Dyson is not doing science, but he is deluding others under the guise of science. Given’s Dyson’s evident love of science (and expertise in it), that’s the part that we still don’t get.

http://www.realclimate.org/index.php/archives/2011/02/the-starship-vs-spaceship-earth/

Fastest disinformer retraction: Watts says Goddard’s “Arctic ice increasing by 50000 km2 per year” post is “an example of what not to do when graphing trends”

Fastest disinformer retraction: Watts says Goddard’s “Arctic ice increasing by 50,000 km² per year” post is “an example of what not to do when graphing trends”

Plus science blogosphere roundup: "Fred Pearce is a rubbish journalist" and Eric Stieg on PNAS

by Joseph Romm, Climate Progess, July 3, 2010

Ironygate:  The king of cherry picking just threw the prince (jester?) of cherry picking under the bus for picking some really, really bad cherries:

Thank you Anthony Watts for leaving this nonsense on your blog and acknowledging it as “an example of what not to do when graphing trends, to illustrate that trends are very often slaves to endpoints” — as opposed to 99% of your other posts, which you continue to embrace even though they are also examples of what not to do, such as these recent absurdities:

“The death spiral continues, with Arctic ice extent and thickness nearly identical to what it was 10 years ago.” (5/31)

“Over the last three years, Arctic Ice has gained significantly in thickness….  Conclusion : Should we expect a nice recovery this summer due to the thicker ice? You bet ya.” (6/2)

“Arctic Basin ice generally looks healthier than 20 years ago.” (6/23)

Those laughable conclusions should have been a warning sign to Watts not to keep posting Goddard’s nonsense — except, of course, nonsensical graphing, cherry picking endpoints, and generally making up stuff is what Watts specializes in (see links below).

Since I generally don’t read WattsUpWithThat, except when I am doing a post on Arctic ice and looking for a good LOL, I wouldn’t have actually caught this if I hadn’t been reading the comments at Tamino, one of which notes:

BTW, “the mistake was noted by Steven immediately after publication,” is Watts-speak for “Ian H pointed it out in comment #3 within maybe 15 minutes after the posting.”

Tamino has a good post debunking Watts/Goddard on Arctic ice thickness (here).

This CP post originally began as a round up of science blogs, with this opening:  The bad news is there’s too much damn stuff to report on or debunk.  The good news is there’s a lot of good analysis and debunking in the science blogosphere.

Who knew that the debunking would be by the disinformers themselves!

Here’s more:

• Fred Pearce is a rubbish journalist (The Way Things Break):

If anyone needs evidence that the “reporting” crutch of He Said, She Said is still being employed by stenographers masquerading as journalists, here’s Fred Pearce in New Scientist.
No serious effort is made to inform the reader which of the parties is actually supported by reality. Note the weasel wording and false balance throughout, e.g.: “some of the researchers involved take issue with a suggestion that greenhouse gases are not primarily responsible for global warming”; “Foster’s team concludes… But de Freitas says”; “The vitriol continues”; etc.

It’s a stereotypical example of the “on the one hand, on the other” style that has so distorted the public’s understanding of the issue of anthropogenic climate change.

It’s 2010, FFS. This article should be held up as a model for how reporting should not be done.

• I’ll start calling them skeptics when they start being skeptical (Deltoid)

Last week, CEI’s Christopher Horner, writing at Pajamas Media claimed that Gabriel Calzada (author of a dodgy study claiming that Spain’s green energy program had cost many jobs) had been mailed a dismantled bomb by a solar energy company. As Ed Darrell observes, the story is preposterous (even without considering the source), but a whole lot of self-styled global warming skeptics uncritically accepted it. And even after the story was completely retracted, folks like Anthony Watts and Andrew Bolt did not make corrections.

• What do climate scientists think? (Real Climate) Gavin Schmidt and Eric Stieg [!] set the record straight on …

… a new paper in PNAS (Anderegg et al, 2010) that tries to assess the credibility of scientists who have made public declarations about policy directions….

It is completely legitimate to examine the credentials of people making public statements (on any side of any issue) – especially if they make a claim to scientific expertise.  The database that Jim Prall has assembled allows anyone to look this expertise up – and since any new source of information is useful, we think this can be generally supported. Prall’s database has a number of issues of course, most of them minor but some which might be considered more problematic: it relies on citation statistics, which have well-known problems (though mostly across fields rather than within them), it uses Google Scholar rather than the standard (ISI) citation index, and there are almost certainly some confusions between people with similar names. Different methodologies could be tried – ranking via h-index perhaps – but the as long as small differences are not blown out of proportion, the rankings he comes up with appear reasonable….

So, do the climate scientists who have publicly declared that they are ‘convinced of the evidence’ that emission policies are required have more credentials and expertise than the signers of statements declaring the opposite? Yes. That doesn’t demonstrate who’s policy prescription is correct of course, and it remains a viable (if somewhat uncommon) position to acknowledge that despite most climate scientists agreeing that there is a problem, one still might not want to do anything about emissions. Does making a list of signers of public statements, or authors of the IPCC reports, constitute a ‘delegitimization’ of their views? Not in the slightest. If someone’s views are widely discounted, it is most likely because of what they have said, not who they sign letters with.

However, any attempt to use political opinions (as opposed to scientific merit) to affect funding, influence academic hiring, launch investigations, or personally harass scientists has no place in a free society – from whichever direction that comes. In this context, we note that once the categorization goes beyond a self-declared policy position, one is on very thin ice because the danger of ‘guilt by association’. For instance, one of us (Eric) feels more strongly that some of Prall’s classifications in his dataset cross a line (for more on Eric’s view, see his comments at Dotearth).

More on PNAS soon.

Related posts on Watts:

• Wattergate: Tamino debunks “just plain wrong” Anthony Watts
• Hits charade: WattsUpWithThat hypes itself with dubious webstats, while lowballing other blogs
• Watts not to love: New study finds the poor weather stations tend to have a slight COOL bias, not a warm one
• FoxNews, WattsUpWithThat push falsehood-filled Daily Mail article on global cooling that utterly misquotes, misrepresents work of Mojib Latif and NSIDC
• WattsUpWithThat says it has “nothing to do with the dreaded Climate Change” and “has an unappreciated benefit”!
• Exclusive: New NSIDC director Serreze explains the “death spiral” of Arctic ice, brushes off the “breathtaking ignorance” of blogs like WattsUpWithThat
• Diagnosing a victim of anti-science syndrome (ASS)

Ted Scambos, Eric Steig, Tom Neumann, IPY, U.S.-Norwegian South Pole Traverse

ANTARCTICA NEWS ARCHIVES

---

Photo credit:Lou Albershardt

IPY Traverse Posted: May 6, 2009 Courtesy: Antarctic Sun

by Peter Rejcek The 12 scientists and support staff who made a slow crawl across a vast, blank stretch of East Antarctica this past austral summer for three months to study how regional climate variability relates to global climate change expected to encounter brutally cold storms and other challenges on the high polar plateau. They didn’t expect to come across other travelers in the relatively unexplored area known as Queen Maud Land. But they did — three times in one day. “We were astonished because we were supposed to be all alone,” said Ted Scambos , a member of the Norwegian-U.S. science team that crossed a large slice of the Antarctic continent using tracked vehicles pulling sleds. “I don’t know where you can go in order to be on the edge of the Earth anymore.” The encounters, all involving people taking part in a commercial race to the South Pole, occurred near a fuel depot in an area where the ice sheet was more than 3,000 meters thick, hiding at least four distinct subglacial bodies of water called the Recovery Lakes. “Fuel depots in Antarctica are kind of the equivalent of watering holes in Africa,” mused Scambos, lead scientist at the Boulder, Colo.-based National Snow and Ice Data Center. “Everybody has to come to the fuel depot, and you see all kinds of people, all kinds of groups, gathered at the fuel depot.” But for most of the roundtrip journey between Norway’s Troll research station on the coast and the U.S. Antarctic Program’s South Pole Station , the scientists and crew were on their own. They took measurements of the snow and ice in areas that virtually no one had visited since the late 1960s, when the United States primarily used tractor trains to conduct deep-field science work. Living and working out of bright red, boxed buildings mounted on sleds, the team collected ice cores at various depths and locations, used radar to map the ice sheet layers and dug snow pits — all in an effort to understand the climate in this area for the last thousand years and how it may be changing today. The project was part of the International Polar Year , a 60-nation effort to better understand the Antarctic and Arctic, which officially ended last month. “It’s really been a blank spot on the map — on both the literal map as well as the metaphoric map of climate change in Antarctica,” said Tom Neumann , leader of the traverse team during the second leg of the two-year project that began in 2007-08 and covered nearly 7,000 kilometers including a few side trips. “[The traverse] should help fill in the picture of how Antarctica overall is changing.” Scientists had believed that Antarctica was largely bucking the global warming trend. While West Antarctica was undoubtedly heating up — particularly the outstretched tip of the Antarctic Peninsula where ice shelves are disappearing at historic rates — studies of the much larger East Antarctic Ice Sheet suggested a cooling trend. Some researchers have suggested the depletion of stratospheric ozone over Antarctica — the ozone hole that appears each austral spring — is affecting atmospheric circulation and westerly winds around the continent, effectively shielding it from global warming. But a paper in the journal Nature earlier this year said warming in West Antarctica is greater than whatever cooling may be occurring on the rest of the ice-covered continent. “Simple explanations don’t capture the complexity of climate,” explained Eric Steig , lead author of the Nature paper and a professor at the University of Washington , in a statement back in January. “The thing you hear all the time is that Antarctica is cooling, and that’s not the case,” added Steig, a collaborator on the IPY traverse project. “If anything it’s the reverse, but it’s more complex than that. Antarctica isn’t warming at the same rate everywhere, and while some areas have been cooling for a long time, the evidence shows the continent as a whole is getting warmer.” Antarctica is roughly the size of the United States and Mexico: Snow in Denver doesn’t mean a blizzard stretches all the way down to Mexico City. “Antarctica is a huge place, and I would be surprised if it was all doing the same thing,” said Neumann, a scientist now with NASA Goddard Space Flight Center . Yet there’s even a hint that East Antarctica — well, at least one spot on that incomplete map — may be warming based on one initial experiment by the traverse team. Scambos deployed strings of highly sensitive “thermometers” called thermistors into two of the deeper ice core holes. The temperature on the ice sheet surface changes with the weather, but the temperature deeper down changes very slowly as the climate changes. Neumann likens it to throwing a frozen turkey into the oven — not the best way to cook a turkey, for sure, but eventually the center starts to thaw and cook based on the long-term outside temperature. “It takes a while for the ice at 90 meters to notice how the surface temperature has changed,” Neumann explained. At that depth, the ice temperature is determined by the average temperature of the last 50 years or so. The instruments will operate for the next several years, allowing the scientists to determine how surface temperature changes through time. “The initial results do say these areas are warming,” Neumann said, stressing that the measurements are in the hundredths of a degree per year and the data still raw. Scambos: Recovery Lakes region was likely marine embayment in distant past Most of the scientific analysis is yet to come. Neumann and others on the team will use the ice core samples to conduct stable isotopic measurements. By studying the isotopic ratios of oxygen 16 and oxygen 18, for instance, researchers can figure out what the climate was doing at a particular time because different ratios indicate different types of climate. The chemistry will help the team calibrate the radar returns of the ice layers, a key step to nailing the snow accumulation rates in East Antarctica — one part of the equation to whether the ice sheet is overall losing or gaining mass. Loss of mass would indicate a rise in sea level. “The chemistry from the core helps because it tells you the accumulation rate at a point,” Neumann explained. “For example, how deep is the fallout from the 1960s above-ground nuclear testing? That information helps to calibrate the radar layers that intersect the core site. “If a radar layer is shallower, then it has had relatively less accumulation; a deep layer reflects relatively more accumulation. The information form the core lets you quantify the ‘relative’ statements above.” The scientists also took the opportunity to explore the Recovery Lakes, an area of at least four lakes at the head of one of the largest ice streams draining East Antarctica. Ranging in size from 600 to 1,500 square kilometers, at depths well below sea level, the lakes were likely part of a deep marine embayment millions of years ago when the ice sheet was much smaller, according to Scambos. “It was probably dynamic in the past,” he said. “In the distant future, if the Earth gets a great deal warmer, it would be dynamic again. I would prefer to think that we’ll stabilize climate change before we have to worry about this part of Antarctica disintegrating.” There is still a lot of uncertainty about what the Antarctic ice sheets may do in the future because so little of it has been measured, particularly compared to Greenland, according to Neumann. “The uncertainties in Greenland are getting quite a lot smaller as we get more and more data about ice velocity, ice thickness and accumulation rate. It’s certainly negative [mass balance] and we know roughly how negative it is in Greenland,” he said. “Antarctica is a bit of a different story, because it is so much larger and there’s places with so much less data, such as in East Antarctica. “The physical insight is coming along and the model development is coming along, but I think it’s going to be a quite a while before we really have confidence in the large-scale predictive models of ice sheet change,” he added. More ground-based studies like the traverse would help to continue filling in the blank spots of the climate change map, according to the scientists. “Most of that uncertainty [about Antarctica] can be beaten down with more and more measurements of accumulation rates,” Neumann said. “The traverse system that the Norwegians have put together is fantastic, state-of-the-art. It’s the best in the world right now in terms of supporting a science crew over long distances,” Scambos said. “They essentially have a mobile, 12-person base that provides them relatively easy access to a large area. … [Queen Maud Land is] one of the least-explored areas of Antarctica, and I think that’s going to change, in part, thanks to this traverse system they’ve got.”

Link to this article:
http://antarcticsun.usap.gov/science/contenthandler.cfm?id=1758