Briffa's Tree Ring Evidence Undermines "Hockey Stick" Global Warming Graph
"The group expressed 'regret' last month for an erroneous projection in its influential 2007 climate report that the Himalayan glaciers could melt by 2035." Source of caption and photo: online version of the WSJ article quoted and cited below.
(p. A12) The problem: Using Mr. Briffa's tree-ring techniques, researchers in the '90s built charts suggesting temperatures in the late 20th century were the highest in a millennium. The charts were dubbed "hockey sticks" because they showed temperatures relatively flat for centuries, then angling higher recently.
But Mr. Briffa fretted about a potential issue. Thermometers show temperatures have risen since the '60s, but tree-ring data don't move in tandem, and sometimes show the opposite. (Average annual temperatures reached the highest on record in 2005, according to U.S. government data. They fell the next three years, and rose in 2009. All those years remain among the warmest on record.)
In his same 1999 email, Mr. Briffa said tree-ring data overall did show "unusually warm" conditions in recent decades. But, he added, "I believe that the recent warmth was probably matched about 1,000 years ago."
In other words, maybe the chart shouldn't resemble a hockey stick.
The data were the subject of heated back-and-forth before the IPCC's 2001 report. John Christy, one of the section's lead authors, said at the time that he tried in vain to make sure the report reflected the uncertainty.
Mr. Christy said in an interview that some of the pressure to downplay the uncertainty came from Michael Mann, a fellow lead author of that chapter, a scientist at Pennsylvania State University, and a developer of the original hockey-stick chart.
The "very prominent" use of the hockey-stick chart "overrules what tentativeness some of us actually intended," Mr. Christy wrote to the National Research Council in the U.S. a month after the report was published. Mr. Christy, a climate scientist at the University of Alabama in Huntsville, provided that email.
"I was suspicious of the hockey stick," Mr. Christy said in an interview. Had Mr. Briffa's concerns been more widely known, "The story coming out of the [report] may have been different in tone and confidence."
For the full story, see:
JEFFREY BALL And KEITH JOHNSON. "Push to Oversimplify at Climate Panel." The Wall Street Journal (Fri., February 26, 2010): A1 & A12.

Hockey stick graph is on top; more accurate, but much less publicized graph, is on bottom. Source of graphs: online version of the WSJ article quoted and cited above.
















Source of graph: online version of the NYT article quoted and cited below.
Source of image: online version of the WSJ article quoted and cited below.
Environmentalists should salute Boy Scouts for drinking from reusable canteens. (This is the first time I ever remember a photo of a Boy Scout making it into the Times SundayStyles section.) Source of photo: online version of the NYT article cited above.
"An iceberg as seen off the coast of Twillingate in Newfoundland." Source of caption and photo: online version of the WSJ article quoted and cited below.
Brian Bryne (sic), a New York City artist, along with a partner, bought this Newfoundland house as a speculative investment. Source of photo: online version of the WSJ article quoted and cited above.
Part of a Greenpeace ad lambasting Senator Edward Kennedy's opposition to windmills that would effect his view. Source of image of part of ad: online version of the WSJ article quoted and cited below.
Source of map: online version of the NYT article cited above.
Source of graphs: online version of the NYT article cited below.
Source of image: online version of the WSJ article cited below.
Source of the map: online version of the NYT article quoted and cited above.
Source of map: online version of the NYT article cited above.
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Wildcatter entrepreneur "Joseph H. Bryant started Cobalt." Source of caption and photo: online version of the NYT article cited above.
The bulb I like, but don't want to be forced to use. Source of image: online version of the WSJ article cited above.
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Al Gore dreams of Rachel Carson. Source of image: online version of the WSJ article cited below.
Kern River pipelines in front, and pump in back. Source of graphic and photo: online version of the NYT article cited above.