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Showing posts with the label tony heller

Data Tampering by Shewchuk and Heller

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If you follow climate discussions on X, you're bound to see John Shewchuk and/or Tony Heller show graphs that reportedly show that NOAA is tampering with temperature data to fabricate global warming with spurious warming trends. I've gone over many of the reasons why this is nonsense before in posts about bias correction and so-called  ghost stations . I think it's good to show what's actually going on with the graphs they present as "proof" of data manipulation, though. I think it can be easily demonstrated here that it's actually Shewchuk and Heller that are tampering with data. Shewchuk (Top) and Correct (Below) Above are two graphs. The top graph shows what John Shewchuk claims shows that NOAA is manipulating data. It shows USHCN "raw" and "altered" Tmax data for 1900 to 2023. The bottom graph above is the correct plot of NOAA's published data from the current and correct dataset ( nClimDiv ) with a 5-year running mean to m...

Tony Heller's Proxy Trick

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Recently I've seen people posting the following graph from Tony Heller, which is intended to show a cooling trend in temperatures following the 1940s and suggest that the "start of the satellite record" begins when temperatures are at their low point. Heller's graph is unsourced except for being called "Briffa's Reconstruction." This graph has shown up on Twitter, and so far I haven't seen any one identify the source of this data or even what the data represents. However, I was able to determine that up through 1960, the data is identical to Briffa 2001[1], and the data is on an Excel spreadsheet on an FTP site maintained by NOAA for plate 3 of Briffa's paper. The same site also has regional data that includes years following 1960 (plate 2 in Briffa's paper), but Briffa is clear that the post-1960 data does not have a clear temperature signal. Briffa writes, "The period after 1960 was not used to avoid bias in the regression coefficients...