Global Weather Dataset being Systematically Corrupted by Terry Hurlbut, Examiner.com
It looks like the fraudsters are changing the raw data ... to hide their crimes?
Sunday, December 13th 2009, 2:01 PM EST
Co2sceptic (Site Admin)
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.
climaterealists.com
Alaska Climate – Station Data vs Adjusted GHCN/IPCC
By Dr. Richard Keen, University of Colorado
I recently completed a study of central Alaska's climate. For this study I computed the average annual temperature for nine long-term Alaskan stations (and station combinations), which are: Eagle/Dawson, Ft. Yukon/Central, Fairbanks University, McKinley Park, Talkeetna, Gulkana/Kennecott/Chitina/McCarthy, Yakutat, Cordova, and Valdez.
Then I averaged the nine stations for a regional mean. The data source was NCDC. The annual values on the next plot clearly show the dominance of the PDO in Alaskan climate.
For comparison with the IPCC thumbnail for Alaska (I hope you can find an enlarged version of this), I replotted the regional temperatures as ten-year averages. My averages show that the past three decades have shown no warming (since the PDO shift in 1977), and are in fact no warmer than the 1935-1944 decade. This is very different from the IPCC which shows a substantial warming over the past three decades.
See the plot of annual versus the PDO stages.
Here is the GHCN annual temperatures for the same region. The GHCN data is dominated by an upward trend. My analysis gives an upward linear trend of 0.69 C/century (due to starting during a cold PDO and ending during a warm PDO), while the
GHCN trend is 2.83 C/century - over 2 degrees larger!
My study and the GHCN use the same stations, because there are no other long-term stations in the regions. I applied no "corrections" beyond offsets used when combining two or more stations with overlapping records (no other adjustments were warranted). Here is a blow up of the IPCC graph for Alaska.
One can only guess what "corrections" were applied to the GHCN and IPCC data sets, but I can easily guess their magnitude - about 1 degree. Curiously, the magnitude of the adjustments is about the same as the "global warming" signal of the past century.
I'd be interested if other readers can provide similar comparisons with other parts of the world.
icecap.us |
