Search Results for: strip bark

Strip Bark Growth Pulses

CA readers know that virtually all of the “independent” IPCC reconstructions purporting to compare modern and MWP temperatures use Graybill strip bark chronologies and/or Yamal. In various posts, problems with strip bark chronologies have been discussed, including discussion of Pete Holzmann’s observation based on our sampling at Almagre that strip bark trees seemed to show […]

Miracles and Strip Bark Standardization

A CA reader has provided a link to an extremely interesting presentation by dendro Brian Luckman of U of Western Ontario (Rob Wilson’s thesis supervisor) at the 2008 Canadian Society of Petroleum Geologists. Reader Erasmus de Frigid draws attention to the inhomogeneity in the tree ring record created when the tree was scarred by a […]

Strip Bark at Upper Wright Lakes Foxtails

As a sort of Methadone replacement for Mann’s bristlecone PC1 (which uses Graybill’s strip bark chronologies), two Esper foxtail chronologies (Upper Wright Lakes and Boreal Plateau) have come into use by the Team. These two chronologies were used separately in the small Esper network (two of only 7 or so medieval chronologies) making a very […]

Almagre Strip Bark

I’ve got some preliminary measurement data back on several trees with Graybill tags in digital form. The dendro lab is working on cross-dating this week. The measurement data for our Tree #31 (Graybill 84-56), which Pete Holzmann posted a picture of earlier today, is very interesting. This is a strip-bark tree – remember that the […]

BBC’s Fake Climate Audit Screengrab

On October 18, 2021, BBC (producer Owen Sheers) aired a “conspiracy thriller” entitled The Trick – though a more complete title would have been The Trick… to Hide the Trick to Hide the Decline. In a forthcoming post, I’ll do a longer analysis of the trick in which, to borrow a phrase from Climate Audit […]

PAGES2K: North American Tree Ring Proxies

The PAGES (2017) North American network consists entirely of tree rings. Climate Audit readers will recall the unique role of North American stripbark bristlecone chronologies in Mann et al 1998 and Mann et al 2008 (and in the majority of IPCC multiproxy reconstructions).  In today’s post, I’ll parse the PAGES2K North American tree ring networks […]

A Return to Polar Urals: Wilson et al 2016

Wilson et al 2016, like D’Arrigo et al 2006, includes a ‘Polar Urals’ chronology as one of its components.  Tree ring chronologies from Polar Urals and Yamal have long been a contentious issue at Climate Audit, dating back to the earliest days (see tags Yamal, Polar Urals). Whereas the D’Arrigo et al 2006 version had one […]

Rahmstorf’s First Trick

In any article by Mann and coauthors, it is always prudent to assume that even seemingly innocent choices use up a researcher degree of freedom – to put it nicely. For example, Rahmstorf et al focus on their “AMOC index” in the period ending 1995 and show their AMOC index up to as shown below.

Reductio ad mannium

The new article by Rahmstorf and Mann (see RC here) has been criticized at WUWT (here here) for making claims about Atlantic Ocean currents based on proxies, rather than measurements. (Also at Judy’s here)   But it’s worse, much worse than we thought. Rahmstorf and Mann’s results are not based on proxies for Atlantic current velocity, but […]

ClimateBallers and the MM05 Simulations

ClimateBallers are extremely suspicious of the MM05 simulation methodology, to say the least.  A recurrent contention is that we should have removed the climate “signal” from the NOAMER tree ring network before calculating parameters for our red noise simulations, though it is not clear how you would do this when you not only don’t know the […]