Lonnie Thompson has done a much better job of archiving data for his recent update Quelccaya – see NOAA here – both in terms of information and promptness.
Quelccaya is familiar territory for Thompson as it was the location of his first tropical ice cores (1983) and his first publication of this type. Thompson published a first update of Quelccaya d18O values in 2006 (PNAS) but only 5-year average data and only to the late 1990s. The new dataset gives annual data (previously available from the 1983 cores from 470 to 1983) from 226 to 2009.
Below is a graphic showing twentieth century on, comparing to the PNAS 2006 five-year data. The extension covers the big 1998-99 El Nino with a dotted red line. Since 1998-99 is known to be an exceptionally warm year, it is interesting to observe that it is manifested at Quelccaya as an negative downspike.
There has been a longstanding dispute about whether d18O at Quelccaya and other tropical glaciers is a proxy for temperature or for the amount of precipitation. In monsoon region precipitation, negative d18O values show rain-out. Quelccaya d18O has been (IMO plausibly) interpreted by Hughen as evidence of north-south migration of the ITCZ, with Hughen comparing Quelccaya information particularly to information from Cariaco, Venezuela.
It seems to me that, among specialists, Thompson is probably standing fairly alone in claiming that d18O at tropical glaciers is a proxy for temperature rather than amount effect. (Because of Thompson’s eminence, the contradiction of his results is mostly implied, rather than directly stated.) Despite these reservations among specialists, Thompson’s d18O records have been widely cited by Mann and other multiproxy jockeys (both directly and through the Yang composite) and are important contributors to some of the AR4 Hockey Sticks. “Dr Thompson’s Thermometer” was proclaimed in Inconvenient Truth as supposedly vindicating the Mann Hockey Stick, although the graphic shown in AIT was merely the Mann hockey stick wearing whiskers, so naturally it confirmed itself.
Because the 1998 El Nino was so big, it provides a good test case for temperature vs amount. It seems to me that the negative downspike for the big 1998 El Nino is decisive against Thompson.
The PNAS version of the data left off showing a sort of uptick. The extension to 2009 does not seem to me to be going off the charts.
Update Apr 8. here is a comparison of Quelccaya O18 to HadCRU GLB (both scaled over the 20th century). I’ve used GLB because Quelccaya is used to deduce global temperatures in multiproxy studies, not temperatures at Cuzco. Quelccaya O18 values obviously do not capture the temperature trend. Marcott/Mann defenders say that we don’t need proxies to know that temperature has gone up in the 20th century. Quite so. Quelccaya was not a Marcott proxy, but it was important in Mann et al 2008 and other multiproxy reconstructions. What does this sort of thing really tell us?
Anthony’s coverage of the release of this data prompted some discussion of the Thompsons as serial non-archivers, referring to my post here. It is worth commending Thompson for prompt archiving of the present data, but that does not refute past criticism of both Ellen and Lonnie. (I note that Thompson has mitigated some of that criticism by archiving some data on old cores, even within the past year.)
The post in question actually was directed at Ellen Mosley-Thompson, who, as far as I can tell, has not archived a single data set in which she was lead PI in over 30 years in the business. I stated the following:
She has spent her entire career in the ice core business> According to her CV, she has led “nine expeditions to Antarctica and six to Greenland to retrieve ice cores”. However, a search of the NOAA paleo archive for data archived by Ellen Mosley-Thompson shows only one data set from Antarctica or Greenland associated with her. Lest this example be taken to mar her otherwise unblemished record of non-archiving, the data was published in 1981 while she was still junior and, according to its readme, it was transcribed by a third party and contributed in her name. I believe that it’s fair that she has not archived at NOAA (or, to my knowledge, elsewhere) any data from the “nine expeditions to Antarctica and six to Greenland”.
I did a fairly thorough review of Thompson’s non-archiving as of July 2012 here. Nick Stokes at WUWT claimed that my posts were refuted by his being able to locate Thompson data at NOAA. Unfortunately, this is the sort of misdirection that is all too prevalent in the field.
I am obviously aware of the NOAA archive. While, like anyone else, I make my share of mistakes, the odds of me being wrong in the trivial way that Stokes asserted are negligible. While Ellen is listed as a co-contributor on expeditions led by Lonnie, the above statement is true as written.
Nor does Nick’s location of NOAA archives (which I know intimately) refute my criticisms of Thompson’s archive here. The Lonnie situation is much less bad than when I started criticizing him: when I first got interested, no data for Dunde, Guliya or Dasuopu had been archived and Thompson blew off requests for data. Matters are less bad, but still very unsatisfactory. Inconsistent grey versions of Dunde and other series are in circulation. This can only be sorted out by archiving all samples together with dating criteria. I’ve characterized such an archive as Thompson’s legacy – something that he should be proud of and not resist.
I’ve also strongly criticized Thompson’s failure to archive the Bona-Churchill data, sampled long before the recent Quelccaya data. This data was already overdue in 2006, when I first criticized its non-publication and non-archiving. At the time, I observed (somewhat acidly, I’ll admit) that if the data had a big upspike in the late 20th century, Thompson would have press released and published. Because the dog didn’t bark, I predicted that the data went the “wrong” way. Seven years later, Thompson still hasn’t published Bon-Churchill, though results were shown at a workshop a number of years ago, showing that they did indeed go the ‘wrong” way, as I had surmised.