For the past six days, several climate scientists have discovered an alarming trend: clear evidence of alteration of historical data at weather stations around the world, in order to support the contention of anthropogenic global warming (AGW).
The changes appear to affect the Global Historical Climate Network (GHCN), a project of the National Oceanographic and Atmospheric Administration's National Climate Data Center. Note that this is the same agency that employs Dr. Eugene Wahl, who might be implicated in the research misconduct allegations made against Michael E. Mann at Penn State University.
Richard Keen at the University of Colorado was the first to notice the changes. On December 5, he published this report
comparing his own research into the climate of Alaska with the official version of the UN Intergovernmental Panel for Climate Change (IPCC). He found no evidence of warming in Alaska over the past three decades, and no substantial difference in average temperature between 1935-1944 and the present time. Overall he found a warming trend of 0.69 Kelvin per century over the span of the twentieth century--while the GHCN dataset projects a warming trend of 2.83 K/century. (The Kelvin is the International System equivalent of a Celsius degree.)
Keen published his findings at icecap.us. They were little noticed until three days later, when Willis Eschenbach published this entry
at WattsUpWithThat, containing an analysis of the raw data at the weather stations in and around Darwin Airport in Australia, and the data as adjusted by GHCN. Eschenbach charged that the Darwin data had been distorted, not adjusted, and suggested that the data ought to have been left alone, or else given one single adjustment, downward by 0.6 Kelvin, of the temperature record of 1941 and prior. The result of the official adjustments was a linear warming trend of 1.2 K/century, whereas the raw data showed a cooling trend of 0.7 K/century. Had the data received the single adjustment proposed by Eschenbach, the trend might have been nearly flat.
Worse yet, says Eschenbach, the data from just one station, identified as Station Zero or Darwin Zero, received an adjustment giving it a warming trend of 6 K/century.
Those, dear friends, are the clumsy fingerprints of someone messing with the data Egyptian style … they are indisputable evidence that the “homogenized” data has been changed to fit someone’s preconceptions about whether the earth is warming.
Eschenbach admitted at the time that his findings at Darwin could be an isolated case. But shortly after the Eschenbach entry appeared on WattsUpWithThat, a reference to it appeared at The Air Vent, whereupon a reader mentioned and linked to Keen's Alaska study. Furthermore, another blogger published this entry
(repeated here at WUWT
) concerning faulty weather-station siting in Western Australia.
Today, Anthony Watts himself reported on a comment
by a reader on the most disturbing finding yet: several GISS station datasets have been altered. The only reason why Watts and his commenter could detect the deletion is that Watts had saved the data from two of the affected weather stations (Orland, CA and Fairmont, CA) two years ago. The alteration at Orland is more serious: prior temperature records (between ca. 1880 and 1900), clearly warmer than subsequent temperatures, are now missing. Those data were in place as recently as 29 December 2008 and are not present today. By way of explanation, the GISS data selector (captured by Watts) says this:
Note to prior users: We no longer include data adjusted by GHCN and have renamed the middle option (old name: prior to homogeneity adjustment).
Watts suggests that the problem might be not with the GISS data but with the GHCN dataset upon which GISS depends for historical data.
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Source Link: examiner.com