Greg Hullender writes "Former weatherman Anthony Watt, who runs the major climate-change-denial website "Watt's Up With That," today posted a press release announcing he and associates have found a major problem in the NOAA temperature records over the 1979 to 2009 period. He claims that 70% of NOAA thermometers are poorly placed, causing them to report higher temperatures than they ought to, and, further, that NOAA's attempts to correct for this have actually increased the error. Watt argues that this data series has been important to so many analyses that this discovery invalidates most of the climate science done in recent years.
Previous work by Richard Muller (http://berkeleyearth.org/pdf/station-quality-may-20.pdf) showed no significant difference in mean temperatures at urban vs. rural stations, but Watt uses a new methodology for separating "good" from "bad" stations and claims a factor-of-two difference in the change over time."
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