Willis writes: A couple of things. First, I’ve digitized all of the Hegerl proxy data, and placed it here. I sampled it at ~three year intervals, and interpolated the actual years. Second, I took a look at their reconstruction method. They say: The first step of the reconstruction technique is to scale the individual proxy […]
The reconstruction in Hegerl et al (J Clim) was previously used in Hegerl et al (Nature) which provided some information on the number of series and some other particulars, but did not identify the series. In order to show how farcical the Hockey Team claims of “independence” were, I made guesses last spring about the […]
The Hegerl et al 2006 climate reconstruction is finally online here . I’m going to go through the proxies individually before talking about method. Obviously the first one to look for is Mann’s North American PC1. Although they say that they’ve “moved on”, Mann’s PC1 was used in Osborn and Briffa 2006 and was one […]
Last year, when Moberg was published, I pointed out witha slightly arched eyebrow that one of the two most important contributors to any 20th century HS-ness in Moberg was the increasing percentage of subpolar foraminifera (G. Bulloides) in the Arabian Sea – intuitively not a direct indicator of warming. Having visited the foraminifera literature in […]
I think that I can give a very simple explanation of just how bizarre the climate reconstruction by Jim Hansen is. The graph below shows the actual Mg/Ca values for ODP806B, which is used in his reconstruction. The orange point is a modern sample in 27.2 deg C water (a value of 4.5, higher than […]
Lots of interesting things to find when you turn over the rocks of Hansen et al 2006. These are comments on work in progress, but, to say the least, there appear to be some curious decisions and methodologies.
Mg/Ca proxies measure the temperature of calcification of G. ruber, which is not necessarily the same as surface temperature. Dahl et al state G. ruber is present year–round at Site 723B, but experiences blooms during both monsoon seasons and calcifies above 80 m water depth (14–16)…. In accordance with the seasonality of G. ruber in […]
I’ve had a chance to examine Hansen’s argument a little more closely. Structurally it’s a typical splicing argument that we’re familiar with – proxies up to a certain point and then instrumental temperature. In the case of MBH, they use proxies up to 1980 and then compare that to instrumental records. We’re all familiar with […]
We’re going to be hearing more about this – see press release here for example. I’ll add to this headnotes, but, for now, I’ll post up some URLs that some of you may find handy. The underlying article by Hansen et al is at PNAS here. They thank Ralph Cicerone for his review comments. The […]
The NAS Panel used Esper et al 2002 as a comfort series in their spaghetti graph, but did not perform any due diligence on it. As some of you may recall, I’ve had prolonged correspondence with Science, after being stonewalled by Esper, and, as a result of that, have obtained versions of the chronologies used […]
Climate Audit 