Blog Archive

Monday, August 30, 2010

Eli Rabett on Judith Curry's latest bit of sloppiness, which seems endemic at this point

Dear Readers,

I had already posted the abstract of the Liu and Curry paper, but not being privy to the full paper nor having the competence to actually critique it, I had been waiting for my betters to do so -- and so they have.  The post below is Eli Rabett's, and I will also include that from Stoat in a subsequent post.

The comments related to Eli's post are hilarious -- just click on the link provided at the bottom of this post.

Judy and the INTERTUBES
by Eli Rabett, Rabett Run, August 29, 2010

Over at Stoat Judith Curry is learning about the INTERTUBES, given enough eyes, everything is checked. Wm. Connolley, who in a previous life was a modeler with the British Antarctic Survey, put up a detailed criticism of Liu and Curry's recent paper,Accelerated Warming of the Southern Ocean and Its Impacts on the Hydrological Cycle and Sea Ice, which seeks to explain the increasing sea ice extent in the Antarctic winter in the face of a warming Southern Ocean
Associated with the warming, there has been an enhanced atmospheric hydrological cycle in the Southern Ocean that results in an increase of the Antarctic sea ice for the past three decades through the reduced upward ocean heat transport and increased snowfall
but, eventually as it must, Liu and Curry conclude that
The increasing heating from below (ocean) and above (atmosphere) and increased liquid precipitation associated with the enhanced hydrological cycle results in a projected decline of the Antarctic sea ice
The latter has the denialosphere up in arms. That, as they say, is their business.

Hank Roberts has been. . . . annoyed by Liu and Currys' not mentioning (the great mentioner, at least in Web of Science, being the currency of science. Engineers and physicians take cash) Manabe, Spellman and Stouffer, published in 1992 as well as Zwally, Comiso and Parkinson from a decade later on which appear to have. . . .anticipated the Liu and Curry paper (see comments at Stoat and elsewhere). IHRHO the claims of "newness" in the Ga. Tech press release accompanying Liu and Curry, were. . . (Eli is trying to be nice and searching for the appropriate words) a bit over the top

Curry eventually replies to Wm's criticisms in detail, including
3) the hypothesis that you put forward is not novel.

We cite the Zhang 2007 paper that describes a different mechanism that is not inconsistent with ours, but does not include the atmospheric hydrological cycle. I probably read the Manabe et al. paper back in the 1990’s, but didn’t recall it as we were writing this paper. Did any of you (other than Grumbine) actually read the Manabe paper? There is one statement in the Manabe paper that is relevant: “ the reduction in surface salinity resulting from the increase of freshwater supply at the oceanic surface is mainly responsible for the weaker convective activity in the G integration.” This statement is made in a paragraph discussing the deep ocean convection in the Southern Ocean. Manabe doesn’t discuss the increasing sea ice extent in this context. Grumbine connected the dots in the Manabe et al. paper and came up with generally the same idea we did (we came up with the idea via a different route), and describes it in a half sentence. So, our hypothesis is not put forward per se in the Manabe et al. paper. I occasionally check in at Grumbine’s site, didn’t spot his post on the Antarctic sea ice. Note, the Zhang paper did not cite the Manabe paper either; it just doesn't say much about the Antarctic sea ice.
She also mentions that
Hank, see answer to question #3 re the Manabe paper. Why was a press release issued on this? Georgia Tech (along with nearly every other university) encourages researchers to publicize any results that they think are of broad interest. Pretty much anything that gets published in a journal with a press embargo policy (e.g. Science, Nature, PNAS) is in this category.
and Hank points to the obvious
No, that wasn't my question. I understand press releases are routine.
I asked why the language of the press release suggests the idea is new, because it was familiar to me as a casual reader, e.g. Zwalley et al. 2002 mention:
"... [Manabe et al., 1992], gives the counter-intuitive result that the sea ice cover would actually increase with global climate warming ..."
Curry, mounts high horse, and replies
Hank, the paper was reviewed by 3 reviewers at Science and 3 reviewers at PNAS. None of the reviewers mentioned that this was unoriginal (or said we should cite Manabe or Zwalley). Your previous post mentioned the Manabe et al. 1992 paper. I read the paper, see message 43 point 3. They mention increasing snowfall in the context of oceanic deep convection but not in the context of sea ice. As far as I can tell, this is the first time a Zwalley paper has been mentioned in the context of our paper.
Zwally et al. (btw, everyone has been inserting an extra e) has been heavily cited and not to put a fine point on it, but one of those cites is to a 2004 paper by a J. Liu and J. A Curry and Douglas G. Martinson Interpretation of recent Antarctic sea ice variability

Now some, not Eli he hastens to add, might have expected anyone who cites an article to have at least read the abstract, which reads in part
The observed increase in Antarctic sea ice cover is counter to the observed decreases in the Arctic. It is also qualitatively consistent with the counter-intuitive prediction of a global atmospheric-ocean model of increasing sea ice around Antarctica with climate warming due to the stabilizing effects of increased snowfall on the Southern Ocean.
Others, might soldier on and read the first page, which includes this nugget:
[Manabe et al., 1992], gives the counterintuitive result that the sea ice cover would actually increase with global climate warming. The physical processes in the model that cause the predicted sea ice increase are increased precipitation with a warmer atmosphere in polar regions, more snowfall on sea ice, lower salinity in the near-surface ocean layers, more stable mixed layer and reduced heat flux to the surface, and consequently, more sea ice.
At this point the auditors go nuts. Must be a tribal thing.


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