Category Archives: Multiproxy Studies

Wahl and Ammann Again #2

Here’s a pretty little graph that I think that you’re going to see more of. One is using the Wahl-Ammann variation of MBH methodology applied to MBH data; the others are from low-order red noise. Pink – no PC reconstruction from WA without strip-bark and Gaspé; black – from low-order red noise. I worked this […]

Wahl and Ammann Again #1

I asked KNMI what were the studies that had “refuted” our work. It seems to be Wahl and Ammann. I’ve never understood the traction of Wahl and Ammann with climate scientists. I doubt that any of them have worked through the details, but Wahl and Ammann issued a press release that all our claims were […]

Groveman and Landsberg

Jean S pointed out the following quote from the NAS Report and suggested that this be discussed: The first systematic, statistically based synthesis of multiple climate proxies was carried out in 1998 by M.E.Mann, R.S.Bradley and M.K. Hughes (Mann et al. 1998); their study focused on temperature for the last 600 years in the Northern […]

Polar Urals Update and Jones et al 1998

I showed a little while ago the impact of the Polar Urals update on the Briffa 2000 reconstruction – using it instead of the Yamal substitution resulted in an MWP index higher than the 20th century. Today I’ve done the same calculation for Jones et al 1998, this time substituting the Polar Urals update using […]

More on Mongolia

Rob Wilson wrote in today pointing out that D’Arrigo et al 2006 had obtained a correlation to gridcell temperature of 0.58 for the Jacoby Mongolia site chronology, working from original data and not relying on hand-me-down data from Mann and Jones. This is actually higher than the 0.25 reported by Mann and Jones for annual […]

Jacoby in Mongolia

Trying to check even simple things like the correlation of individual Osborn and Briffa 2006 series to gridcell temperature always leads to complications. Today I’ll look at the situation with respect to Jacoby’s Sol Dav, Mongolia series, one of the 6-7 mainstays of Hockey Team reconstructions. Needless to say, nothing can be confirmed. Instead of […]

Bristlecones, Foxtails and Temperature

The relationship of bristlecone/foxtails to gridcell temperature is something that I’ve discussed at length, but, surprisingly, I’ve never illustrated it at the blog. This is a type of relationship that, in some ways, is well suited to blogs. It’s simple to discuss; it’s important. It would be amply illustrated and discussed in business feasibility studies […]

Making Hockey Sticks the Jones Way

I discussed Fisher’s Greenland dO!8 proxy yesterday and thought that it would be interesting to discuss its particular function in hockey stick manufacture in Jones et al 1998. Each hockey stick is, after all, made by a master craftsman. The Greenland dO18 is one of only 10 series in Jones et al 1998. Let’s see […]

Briffa 2000 and Yamal

If you actually look at the medieval proxy index of the "other" studies (Briffa 2000, Crowley and Lowery 2000, Esper et al 2002, Moberg et al 2005), the medieval proxy index is usually just a razor’s edge less than modern proxy index – just enough that the study can proclaim with relief that the modern […]

In the Mail

I’ve reported before that Science decided not to require Osborn and Briffa 2006 to provide supporting measurement data for their Taimyr, Tornetrask and “Polar Urals” (Yamal) chronologies. While I disagree with that decision and may pursue the matter further with them, I asked Osborn to voluntarily provide the measurement data. I received a reply from […]