Yearly Archives: 2008

Mann 2008: the Bristlecone Addiction

I see that the BBC is taking the position that the “evidence” of an MWP-modern differential now is confirmed in so many “independent” studies that the matter is now “incontrovertible”. However these studies are not “independent”; the vast majority of the “independent” studies use the same stale proxy data. In my Erice presentation (which I’ll […]

Mann 2008: Impact of the Missing Data

Jeff Id has an interesting post in which he examines the 148 “missing” series. Check it out. I haven’t verified the calculation, but will do so. I submitted a comment at his blog observing that the two “Fisher” series are actually Dahl-Jensen borehole reconstructions from Greenland. These two series were said to have been used […]

Will the Real Slim Shady Please Stand Up? Re-Mix.

There’s an amusing little incident with the deleted “original” data set that was posted up for a few minutes at Mann’s website – you know, the data set that was first demonstrably referenced by a CA reader in the early morning of Sep 5. (I’ll reserve comment for now on issues relating to the timestamp […]

Ian Jolliffe Comments at Tamino

Ian Jolliffe, a noted principal components authority, has posted a comment at Tamino’s, which repudiates Tamino’s (and Mann’s) citation of Jolliffe as a supposed authority for Mannian PCA. He wrote to me separately, notifying me of the posting and authorizing me to cross-post his comment and stating that we had correctly understood and described his […]

Proxy Screening by Correlation

I’ve made histograms of reported proxy correlations for 1850-1995, as reported in r1209.xls (which contains results for all proxies, unlike SI SD1.xls which withholds results below a benchmark.) The breaks are in 0.1 intervals. On the left is the histogram before screening; on the right, a histogram of the 484 proxies after screening.     […]

Borehole Inversion Calculations

Phil B writes: My day job does include parameter and state estimation using Least Squares and Kalman filtering. I have replicated several of the non-ice borehole temperature reconstructions and I’ll “share” my observations. The inversion problem boils down to finding the solution to the inconsistent set of linear equations Ax~b, where A is a skinny […]

MWP Non-Dendro Proxies #2

OK, I’m starting to get the feel of the new proxy network and have some ideas of what the new Mannomatic is doing. The manouevres have a lot of similarities to the moves in MBH98 and I think that a few main components can be singled out: 1. Once again, as in MBH98-99, the “proxies”, […]

Filling in Punta Laguna

Yesterday Mann archived a new version of his data, a version supposedly without any infilling. Gavin Schmidt is pretending that this was there all along and demanding an apology from one of his readers, who had the temerity to question Schmidt. I’ve taken a quick look at the new (Sept 4, 2008) version of Mann’s […]

Mann et al 2008 Proxies

Here are 5 graphics which show all the Mann 2008 proxies in a consistent format, highlighting two periods 950-1100 and 1850-1980. My software only permits 300 gif images per gif-movie, so 5 parts. The graphics show nicely how few series actually have low-freq variability and how few series are really contributing to any HS-ness. The […]

Mann et al 2008: Korttajärvi

Larry Huldén writes: The Finnish lake sediments can not be used for temperature interpretations in the 18th to 20th century unless you know exactly the history of the regional lake environment conditions. We have 180,000 lakes in Finland. It is very easy to cherry pick among them and say that it is a random sample. […]