Welcome, dear readers. For all of you who have eagerly been awaiting Part II of Les Chevaliers, thank you for your patience; with all the other interesting stuff coming up for discussion at RealClimate, the plans to post Part II ran up against the American Geophysical Union Fall Meeting, when 15,000 of our prime audience are holed up in San Francisco trying to decide which of a half dozen simultaneous sessions at any time best command their attention. Be of good cheer — Part II will be coming along in about another week. Meanwhile, Yours Truly offers a few off the cuff dispatches giving a personal and unedited view of a few things going on at AGU that may be of interest to the RealClimate readership.Myself, I have been spending a lot of time looking at some of the exciting new data coming in from planetary missions, but I’ll spare you that, and talk about things related to global change. I do not pretend that these are necessarily the most important things going on at the meeting, but they are a few things that I happen to have attended, and which caught my attention.
Today, the climate change related session I got to was Climate Change in Greenland: Past and Present (session C13A), with M. Kelley, I. Hakansson and M. Nettles presiding. Actually, I only got to the second half, because of a conflict with a Mars climate poster session, but the half I got to was a real eye-opener. This was a well-attended (really packed, standing room only) session, that generated a lot of excitement. Perhaps I’ll be able to snag some of the images later in the meeting to show you, but meanwhile I’ll do my best to give you some of the picture in words at least.
To put things in perspective, I should first mention the talk by Tom Lowell, on work in collaboration with about a dozen other authors, concerning organic remains from the Istorvet Ice Cap in East Greenland. These are organic remains recently uncovered by the retreating glacier. Dating them tells you when the glacier had last retreated that far. Carbon-14 dates put the date of this earlier glacial retreat to between AD 800 and 1014, bracketing the time of the Norse colonization. Insofar as glaciers are primarily sensitive to temperature, that does indicate that in the Middle Ages this particular place, at least, was probably as warm as at present. It is an indication of some kind of regional warming in the area in the Middle Ages. Thus, if Greenland were taken in isolation, one couldn’t confidently say that what is going on there just now is completely unprecedented in the Holocene — at least not yet. However, as Tom would happily tell you, the Middle Ages were not as generally warm as the present, and Greenland shouldn’t be taken in isolation. It is the rapid melt in Greenland today, taken as one of a vast constellation of signatures of unusual warming, that gives one cause for concern.
And there was ample evidence presented of startling change going on in Greenland — changes in the ice that could raise sea level far beyond the projections given in the IPCC Fourth Assessment Report. J.E. Box and collaborators presented new work on Greenland outlet glacier sensitivity to surface melting. Outlet glaciers are the very dynamic “drains” through which Greenland loses much of its ice. Earlier work by Zwally et al documented the rapid sensitivity of surges in such glaciers to melt water forming on the surface and penetrating to the base. Box and company documented how ubiquitous the melt ponds are, and how every one, basically, is pouring water through a moulin down to the base. Valliant graduate students have waded chest-deep in the melt ponds to measure the rate of drainage. The work documented much more broadly than ever before how outlet glacier speed responds to warming of the environment.
Leigh Stearns and collaborators point out that the Greenland Ice Sheet’s contribution to sea level has doubled in the past five years, due largely to factors connected with ice dynamics (and not incorporated in the IPCC estimates). They showed satellite data which indicates that just two glaciers — Helheim and Kangerdlugssuaq — might account for 10% of this increase. Ominously, more glaciers are primed to pop as climate continues to warm. About the increased flow speeds in this region, they suggest the system has entered a new state: “We speculate that these faster flow speeds represent a new long-term state of behavior which, while not as dramatic as the short-lived periods of peak speeds, have important implications for the rate of sea level rise.”
Mark Fahnestock and collaborators presented additional evidence of the responsiveness of the Greenland ice sheet to climate change around the margins. Changes in outlet glacier systems correlate very well with changes in the temperature of the neighboring sea waters. Some of this may be due to increased melt in the ablation zone, but the effect of warm waters on the calving zone where glaciers discharge into the sea may be a factor,as may be direct mechanical effects of sea ice. The coasts of Greenland have experienced dramatic warming, with satellite data showing the sea having warmed by 4C over the past 15 years. Winter freezing along the coast has shown a dramatic decrease (noticed even by the local Inuit, who in places can no longer traverse certain fjords on dogsled in winter). The dramatic decline in winter freezing shows up in satellite-based sea ice extent maps. If the sea ice goes, can Greenland be far behind? Altogether, things are beginning to look very grim in Greenland — a sentiment expressed by many of the presenters.
Now, that was some of the interesting science, fascinating if scary. Another presentation given today was scary in quite a different way, and altogether aggravating. John Marburger, President Bush’s Science Advisor, gave the Union Agency Lecture. His lecture was called “Reflections on the Science and Policy of Energy and Climate Change.” The good news, I suppose, is that he at least stated that he accepted the established physical connection between CO2 increase and warming — the inhibition of infrared emission by CO2, amplified by water vapor feedback. That’s about the only good thing I can say about the lecture. It was basically an hour long apology for the White House global warming policy. And don’t get me wrong — by “apology” I do not mean that he was expressing regret for the dismal performance of the White House in this sphere.
While acknowledging the correctness of the basic physics, Marburger implied that it was impossible to make useful predictions of climate damages, because of difficulties models have with forecasting regional climate change and things like response of El Nino to warming. Over and over, he castigated the community for being reluctant to do research on adaptation, and over and over stated that adaptation was cheaper than mitigation (reducing CO2 emissions). He stated that it was going to be basically impossible to reduce emissions significantly anyway, since the technologies didn’t exist to do that (I guess he never read Pacala and Socolow’s paper on the wedge concept). His basic answer to everything was that nobody would (or should) do anything until carbon free energy became cheaper than current means of producing energy by burning fossil fuels. There was no recognition that things like carbon taxes might be necessary to put the cost of harms due to climate change into the market. These damages were basically ignored in his world view — except insofar as he said they should be handled by adaptation. “Anthropogenic Climate Change is not the only source of risk to vulnerable populations” He mentioned the need for clean water — the favorite example for everybody who wants to ignore climate change.
He had lots of praise for fossil fuels “Fossil fuels have made modern economies possible.” and echoed the Bush administration line by saying the goal should be to reduce carbon intensity (carbon per $ of GDP) not carbon emissions. Sorry, Dr. Marburger, but infrared radiative transfer doesn’t give a fig about GDP. It’s the emissions that count, and they somehow have to be brought down.
It will be no surprise that Marburger hewed to the line that only voluntary carbon reductions should be sought. He referred to “aspirational goals” as the basis for global carbon policy. More remarkably, he put the blame on Congress when somebody asked why no mandatory carbon caps had been put into place — conveniently ignoring that Congress is within a few votes of passing such a cap, but is laboring under a Presidential veto threat. Even more remarkably, in response to a question about White House censorship and re-writing of documents touching on climate change science, he defended these as “Legitimate attempts to improve the communication of science,” and to “correct some fine points that got glossed over.” He baldly stated, “I have not found any evidence of any attempt to censor science.”
Perhaps somebody should ask Jim Hansen for a second opinion on that. I’m sure our readers can provide Dr. Marburger with additional examples, if he needs a reminder.
Now, I know I am dangerously straying away from the central orbit of RealClimate, and risking touching on politics when I comment on Marburger’s speech. As a major speech presented at a national scientific meeting, I think what was said is probably of interest to our readers, or at least those of us who inhabit the reality-based community. What is going on in the White House very much affects the climate in which science is conducted,and the way scientific results are (or are not) translated into policy. As such, I think this is worth a bit of our attention,and I beg your indulgence. the rest of these dispatches will not stray from the straight and narrow, and will focus on purely scientific commentary.