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Was There a Third "Mike's Nature Trick" to Hide the Decline? Part 3 - Conspiracies Never Die

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WA07 Demonstrating Verification Failure of M&M This is part 3 of a 3 part series on M&M's accusations of "tricks" on the part of MBH and the hockey stick. Part 1 is here and Part 2 is here . Stephen McIntyre is reporting another "Nature Trick" on his ClimateAudit blog. The post is from Nov 24, 2023. As I've pointed out before, the MBH98/99 hockey stick have been replicated so many times that it's really old news. In 2007, Wahl and Amman were able to emulate the MBH98/99 hockey stick reconstruction and verify that it was robust to statistical method. But there were some slight differences between the two, and it seems some people won't be happy until they emulate it exactly.  An "Audit" of MBH98/99 In 2021, Hampus Söderqvist apparently succeeded in doing so. But in the process of doing so, he discovered some minor errors from the infilling of grid box temperatures in Juones & Briffa 1992 that affected MBH98/99. There were appare

Cenozoic Climate and CO2 Proxy Reconstructions

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Cenozoic CO2 and Temperature A new paper was published this month that I think will produce some exciting new insights for those interested in historical geology and paleoclimate studies. The paper is a product of the Cenozoic Carbon dioxide Proxy Integration Project (CenCO2PIP) Consortium, and it looks to reconstruct the proxy evidence for CO2 levels during the Cenozoic (the last 66 million years). The Cenozoic began after the asteroid impact (and/or volcanism) at the Cretaceous-Tertiary (K-T) boundary that caused the mass-extinction that included the extinction of non-avian dinosaurs. The value of this kind of work will have significant benefits for scientists as they seek to constrain estimates for long-term climate sensitivity (ESS). We can think of "sensitivity" on roughly three time scales:  TCR : On a near-immediate time scale, GMST increases with increasing CO2 in what is called transient climatic response (TCR), which generally speaking tells you how quickly temperat

The Hockey Stick and the Mann v. Ball Libel Suit

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By 2007, the MBH98/99 papers had been thoroughly investigated. The MBH hockey stick was found to be robust to statistical method and it was replicated by multiple other reconstructions (above, and discussed  here , here and here ). After the CRU emails were hacked and published, a new set of conspiracy theories were popularized on blogs and YouTube - these were based on a misreading of various emails (discussed  here and here ), but contrarian rhetoric was ramping up to a frenzy. Mann was frequently labeled a criminal and fraud, the hockey stick was called a scam or a hoax.  The Mann v Ball Libel Suit In an interview with the Frontier Centre for Public Policy  (FCPP), Tim Ball was asked, "Various government and academic agencies have whitewashed the Climategate scandal so far. Do you think anyone will be prosecuted for fraud?” Tim Ball's response was, “Michael Mann at Penn State should be in the State Pen, not Penn State.” This was posted on the FCPP website and a series of

Has the "Hockey Stick" Been Disproven? Part 3 - North and Wegman Reports

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Hockey Sticks Featured in the North Report In two previous posts ( here and here ), I described the challenges by McIntyre and McKitrick (M&M) to the initial two hockey stick papers published by Mann, Bradley and Hughes (MBH98 and MBH99). In these posts I summarized M&M's multiple critiques of the MBH hockey stick papers, essentially that the "hockey stick" is an artifact of flaws in the MBH statistical method and an over reliance on one set of North American tree ring proxies. However, multiple peer-reviewed papers following M&M's criticism generally found that M&M's criticisms lacked merit and vindicated the MBH hockey stick reconstruction. To summarize: 1. Biases associated with MBH's statistical method were small and contributed very little to the shape of the MBH hockey stick reconstruction. Biases associated with M&M's statistical method went in the opposite direction, and M&M exaggerated the effect of statistical bias on the

Is Temperature Causing the Increase in CO2?

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Every once in a while a paper gets published in a low-to-no impact journal suggesting that the increase in CO2 concentrations was caused by the increase in global temperatures and not by human emissions. There are several blogs and unpublished manuscripts that make similar claims. Now for sure, since CO2 is less soluble in warmer water, increasing sea surface temperatures, so increasing temperature does cause an ocean-to-atmosphere CO2 flux. But can this explain why CO2 levels are increasing? Some say yes. The most recent paper [1] was published in a no-name MDPI journal called Sci, and Judith Curry promoted it on her blog .  Papers and arguments like this are obviously nonsense, but this paper is a little unique in that it includes the very evidence that proves its central thesis wrong. The following chart comes from the paper. It takes data from the IPCC AR6 accounting of the carbon budget, showing the ocean, land and human sources and sinks. From the numbers the authors included in

Happer Contradicts Himself on Climate Sensitivity

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W. A. van Wijngaarden and William Happer (WH) have periodically attempted to circumvent publishing manuscripts in peer-reviewed journals and have instead taken to uploading manuscripts on the arXiv. As I understand it, the intended use for the arXiv is to allow pre-published manuscripts to be read and evaluated by scientists before the peer-review process is completed. This gives scientists faster access to the newest research, but with the caveat that these manuscripts may need to be revised significantly before being published, once going through the peer review process. Some may not even be published at all, so scientists often look at these manuscripts with interest but also with a grain of salt until the final version passes peer review. WH are apparently using the arXiv to store manuscripts for which they have no intention of submitting to any peer-reviewed journal. The manuscripts are formatted to look like scientific papers, but they will never see the light of day in an academ