Category Archives: Jacoby

The Hockey Stick and the Milankovitch Theory

The 20th century warming counters a millennial-scale cooling trend which is consistent with long-term astronomical forcing. MBH99 According to the UMass researchers, the 1,000-year reconstruction reveals that temperatures dropped an average of 0.02 degrees Celsius per century prior to the 20th century. This trend is consistent with the “astronomical theory” of climate change, which considers […]

Kaufman et al: Obstructed by Thompson and Jacoby

A CA reader sent me an email, noting the following entry in minutes of a meeting. M Loso inquired about Lonnie Thompson’s ice core data. These data are not presently available but will be investigated by Caspar. This comment is minuted in a meeting of PIs leading up to Kaufman et al 2009 – a […]

"Correlates well (r = 0.70) with gridded June–July temperatures"

I’ve been re-visiting some proxy data; I noted last summer that Rob Wilson had archived a considerable amount of B.C. data in Aug 2007 and noticed that he subsequently archived the data versions as used in Wilson et al 2007 at NCDC here in Sept 2007. (Not all of Rob’s data is archived as he […]

Gridcell 47.5N 97.5E: Mongolia

Here’s another gridcell where CRU has truncated high early values. This is the gridcell that contains the important Jacoby Mongolian tree ring series. If untruncated gridcell information is used, then the ring width chronology has a negative correlation to gridcell temperature. What a swamp.

Latitudinal Treeline

A couple of days ago, I canvassed the ITRDB data bank for all tree ring series with values later than 1998, noting that there were many new series. Mann has justified the reliance on proxies not updated since 1980 and earlier, and thus not calibrated against recent warmth, on the basis that it is very […]

Wilson, Pisaric and Gaspé

Two respected dendrochronologists wrote in criticizing my recent post averaging new white spruce chronology contributions to the ITRDB data bank. [Update: see post here with further thoughts on the location of this site. Next post in category] Rob Wilson wrote, using an uncharacteristic Gavin-esque sigh, as follows:

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 […]

Jacoby and D'Arrigo Archive Data!

During the past 20 years, Jacoby and D’Arrigo had obtained over 45 RW series and at least 35 MXD series in North America. To the end of 2005, despite receiivng millions in grants, he had only archived a couple of North American RW series and no North American MXD series. I discussed this before here, […]

A Weird Jacoby-D'Arrigo Series

I mentioned a couple of days ago that Schweingruber et al [1993] seems to arrive at opposite conclusions to Jacoby and D’Arrigo [1989] as to whether anomalous post-1950 ring widths occur (let alone whether that is due to CO2 fertilization or temperature.) It was interesting to compare Schweingruber-Kienast results at Niwot Ridge. It turns out […]