Briffa’s Ph.D. student, Thomas Melvin, discusses the important impact of “modern sample bias” on RCS chronologies, discussing Tornetrask and Finnish sites in detail.
Here’s a beautiful picture of a foxtail pine from the MWP, illustrating eloquently the change in treelines: Original Caption: A dead trunk above current treeline from a foxtail pine that lived about 1000 years ago near Bighorn Plateau in Sequoia National Park.
I have some odds and ends in inventory about bristlecone and foxtail sites, which I’m going to post up, mostly because I find the information rather interesting. Most dendrochronologists assume that the bristlecone/foxtail sites are far too remote to have experienced direct human effects. As far as I’m concerned, this is an assumption that needs […]
The Polar Urals tree ring site is another staple of multiproxy studies, being used in Bradley and Jones [1993], Hughes and Diaz[1994], Overpeck et al. [1997], Jones et al. [1998], MBH98, MBH99, Crowley and Lowery [2000], Esper et al. [2002], Bradley, Hughes and Diaz [2003] and Rutherford et al. [2005] (which recycles MBH98). In fact, […]
Mann has recently provided some inaccurate information on his treatment of bristlecone pines.
There are many regional proxies from around the world that do show the existence of a warm period (warmer than today in most places) called the "Medieval Warm Period" or "Medieval Climate Optimum" roughly from 900-1350AD and a "Little Ice Age" roughly from c.1450 to 1850AD. Amongst the strongest evidence of this is a study […]
Cook et al. [2004] is a “reconstruction of past drought across North America from a network of climatically sensitive tree-ring data”. It uses 835 sites in North American regions overlapping Mann’s PC network. I thought that it would be interesting to compare the two networks. Of course nothing is straightforward when you’re dealing with the […]
In contrast to the claims of the Mann et al "Hockey Stick", practically all proxy records around the world show large scale multi-decadal and century-scale climatic variation. As another example, here are some of the results from a study by Tyson, Holmgren et al (2000,2001) of Lake Naivasha in Kenya and a well documented stalagmite […]
Khim et al. [2002] reported that a core from the Eastern Bramsfield Basin, Antarctic Peninsula showed that the LIA and MWP were the strongest of the Late Holocene cold and warm periods.
Millar, Constance, Robert Westfall, Diane Delany, John King and Harry Alden, Climate As An Ecosystem Architect; Responses Of High-Elevation Conifers To Past Climate Variability.
Climate Audit 