Devasting blow to temperature records in U.S.; Temp trends 'spuriously doubled'

Anthony Watts (Photo credit: Wikipedia)

Anthony Watts, who runs the popular science blog Watts Up With That?, has come out with a breathtaking bare-knuckle press release that will shake the science community's faith in ground-based temperatures to the core: 'New analysis demonstrates that reported 1979-2008 U.S. temperature trends are spuriously doubled'.

In short, Mr. Watts et al write, "The new analysis demonstrates that reported 1979-2008 U.S. temperature trends are spuriously doubled, with 92% of that over-estimation resulting from erroneous NOAA adjustments of well-sited stations upward. The paper is the first to use the updated siting system which addresses USHCN siting issues and data adjustments."

What Mr. Watts and co-author Evan Jones have shown is that half of the warming trend has disappeared because 92% of the so-called rise was caused by "erroneous adjustments of well sited stations". Dr. Richard Muller et al used an older siting classification system.

Muller also wrote a NYT op-ed piece stating the rise in temperatures was caused by greenhouse gas emissions. However, this new classification system shows that siting does have a major impact on the data.

Other findings by Mr. Watts et al include, but are not limited to:

· Statistically significant differences between compliant and non-compliant stations exist, as well as urban and rural stations.

· Poorly sited station trends are adjusted sharply upward, and well sited stations are adjusted upward to match the already-adjusted poor stations.

· Well sited rural stations show a warming nearly three times greater after NOAA adjustment is applied.

· Urban sites warm more rapidly than semi-urban sites, which in turn warm more rapidly than rural sites.

· The raw data T-mean trend for well sited stations is 0.15°C per decade lower than adjusted T-mean trend for poorly sited stations.

· Airport USHCN stations show a significant differences in trends than other USHCN stations, and due to equipment issues and other problems, may not be representative stations for monitoring climate.

Mr. Watts et al promise to continue investigating "other issues related to bias and adjustments such as TOBs in future studies."

The "pre-publication draft paper, titled An area and distance weighted analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends, is co-authored by Anthony Watts of California, Evan Jones of New York, Stephen McIntyre of Toronto, Canada, and Dr. John R. Christy from the Department of Atmospheric Science, University of Alabama, Huntsville, is to be submitted for publication."

You can find the draft paper and related PDFs, as well as reference notes, here.

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