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RE: [cdn-nucl-l] Climate Change Swindle video panned


Jeremy Whitlock wrote:
-----Original Message-----
From: cdn-nucl-l-admin@mailman1.cis.McMaster.CA on behalf of Whitlock, Jeremy
Sent: Wed 3/28/2007 10:07 PM
To: Cdn-Nucl-LISTSERV (E-mail)
Subject: RE: [cdn-nucl-l] Climate Change Swindle video panned
 
Jim writes:

> The best available estimates of temperatures 1000 years 
> ago is the Mann et al. compilation of a variety of temperature 
> proxies from around the world -- the famous "hockey stick".

Jim, I wouldn't exactly call Mann's hockey stick the "best available" -- to
do that ignores the serious statistical errors that have been found in
attempts to replicate his result, including the well-known work by Canadian
scientists Steve McIntyre and Ross McKitrick. 

See, for example, McKitrick's page at:

www.uoguelph.ca/~rmckitri/research/trc.html

and the Nat Post commentary at:

www.canada.com/nationalpost/story.html?id=22003a0d-37cc-4399-8bcc-39cd20bed2
f6&k=0

There is also an interesting discussion of alternative temperature proxies
and the background of the hockey stick phenom at 

www.john-daly.com/hockey/hockey.htm

Regards,
Jeremy. 

=======================

I have some prior (prior to their well-known work) experience with McKitrick and was not very impressed.  You might visit a non-right-wing source of information, the climate blog, RealClimate, at  www.realclimated.org , and do a search on McKitrick.  One of the things you will find is a discussion of the impact on their results of the well-known McK-McI degrees-radians error.

More personally, McKitrick scolded me, justifiably, about 10 years ago for not knowing and accounting for the impact on confidence intervals of time series regressions of autocorrelation in the series.  The McK-McI well-known criticism of Mann et al. makes the same mistake with temporal and spatial autocorrelation, but Ross McKitrick can't claim to be unaware of the need to compensate for the auto- and spatial correlations in the data.

More generally, if all you read is the "right" side of the argument, Lindzen, Spencer, Christy, Michaels, the Idsos, John Daly, Soon, Baliunas, the Robinsons, about a dozen others, the Wall Street Journal, the National Post, the Times of London, and FoxNews, you'll not find anything to challenge you disbelief in anthropogenic global warming.  Reading the IPCC reports (particularly the Technical Summaries, available online), Spencer Weart's The Discovery of Global Warming (a book by Harvard Press, available in an expanded form online), RealClimate (available online and real-time), and the many recent National Academy of Science reports (all of them available online, including one on the hockey stick) will give you a better basis for deciding where the scientific truth lies.
 
Best regards.

Jim Dukelow
Pacific Northwest National Laboratory
Richland, WA
jim.dukelow@pnl.gov

These comments are mine and have not been reviewed and/or approved by my management or by the U.S. Department of Energy.