Happening in Antarctica : Antarctica Melting?

A postdoc publishes a paper based on his doctoral thesis, but ... in his defense presentation consisting of only 35mm slides flipped by someone else, it was indicated that his snow pit samples had melted in transit from Antarctica. He was given his degree regardless. In his paper he claims to be making analyses of ice cores on the Siple Coast. What gives? Here we look a little at his paper, which is included here.

For many, their dissertation is a pinnacle of their careers, an unparalleled achievement, and a compilation of hard, dedicated work over a considerable stretch of time, and an advance in knowledge. The defense is an opportunity to present these ideas to an audience familiar with the work, both as an acknowledgment and approval. Why then, did Richard Alley not have a defense? Instead he told us his thesis melted, and so he had someone show 35mm slides he had made from the day he spent in Antarctica (in total) down in his snow pit. He was not available for comment, questions, or anything. So it appeared that whatever he had done in his pit had melted and so he was going to attempt to acquire his PhD, regardless.

So it was a surprise to me to see that Richard had written a paper on ice core analyses. I wondered, "Where did he get the cores from? What sort of analysis did he perform? Here is his title :

ICE CORE ANALYSIS ON THE SIPLE COAST OF WEST ANTARCTICA (Annals Glaciol, 1988)

It is somewhat nondescript but it give the impression that he did a big study, and also his unpublished dissertation title is : TRANSFORMATIONS IN POLAR FIRN. Whatever transformations he observed, they must have been on these Siple Coast ice cores. Now, why didn't Richard give a talk on these transformations rather than tell us his samples melted? And, why did the faculty let him get away with essentially saying he was going to do nothing for his degree?

Now, I admit I never read his thesis, and it was because of the talk he gave, and the lack of any field work that he did. Admittedly, some transformations are observable in melted ice. The density, I would guess would increase to about 0.92 g/cc.

The thesis is unavailable, so I looked up his paper. Does anyone actually read these? Possibly they just copy bibliographic elements from one paper to another if the title seems appropriate if the author is familiar and positioned at the top of the bibliographic list. This gives the individual a good representation in the science citation index, for example.

One striking fact that emerged : Richard actually did have firn samples from two sites cored by PICO, with density measurements made by D. Susman. Now, Richard himself did measure the snow pit densities at UPB camp (upper 2 meters). So it was not really ICE CORES, but firn cores. Ice gives the impression of drilling into the deeper part of the ice mass, which no doubt was the impression Richard hoped to make. But there were no ice cores, just firn cores that in part possibly melted into icy firn cores.

SO what sort of an analysis did Richard perform? I looked at his conclusions. Restricted to density measurements, any analysis would have to be about that. He says strata in firn record an annual signal. Is that his analysis? That is common knowledge, isn't it? I suppose Richard is telling us he actually saw that in his pit. The one novel statement, not taken directly out of a textbook, is that strong longitudinal deviatoric stresses may affect densification. Now that might require an analysis worthy of consideration. Measured longitudinal stresses will correlate with higher rates of densification. Nope, actually there are no measured longitudinal strains, nor any stress analysis, and so for all we know, the measurements might be erroneous and possibly caused by the simple melting of samples. This, and Ian Whillans, his former graduate advisor, the one who promised Alley a faculty position as an undergraduate, had spent years measuring strains on the Siple Coast including the very locations of the firn cores, and this did not impress Richard at all. Was Ian faking these measurements? Do not ask me. He had a reflector and a EDM device, and some aluminum poles. Richard also did not have any analysis of the ice stream motion to guide him. Was it because there was no realistic model?

This paper is a complete misdirect, giving the impression Alley had ice core analysis experience, when in fact there were no ice cores and no analyses. If he is involved in other analyses, hopefully they will not be as superfluous as this one.

One analysis I would like to see is: if these two cores, the one on ridge BC and UPB, are nepotistic cores, i.e. if they are related, somehow generically, or whether they are dissimilar because of their strain history and provenance. I guess we will just have to wait and see what further analyses Richard Alley will perform for us (or have someone else perform for us).

Another analysis, similar to those in geology(a place where Richard often lifts his ideas and applies them to ice), is to examine the metamorphic changes induced by destressing samples, and thermal cycling of samples. Clearly this places a limit on the information that can be retrieved from cores. This is especially important because Alley's later ice core results in Greenland were observationally difficult and never made by anyone previously, this despite he had only this prior experience with Siple Coast cores.

Since Alley was in the field 1 day, and within earshot of the main Jamesway always, is it possible he was unaware of either surface melting or rain on Whillans Ice Stream? He had only one core. Percolation of surface melt could both explain the UpB camp core, and also irregularities within the temperature profile. If this was an in situ condition, Alley would not know because he was not there when the drilling occurred. It is altogether possible that Alley never saw the firn cores himself, which is fortunate because he chills easily!

Not only did he miss detecting possible melting, but ... he leaves the impression without saying so, that maybe the melting at UPB was natural. He included the lower part of the core in his analysis, even though his study was based on density and the density is anomalously high. So what would an uninformed person think, "Is Antarctica melting?"

I include a copy of his paper to demonstrate the aptness of this commentary.

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