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climate-debate

Ninety-Nine Percent? Re-Examining the Consensus on the Anthropogenic Contribution to Climate Change

by Denteslski et al. , Nov 2023 in MDPI/Springer

Abstract

Anthropogenic activity is considered a central driver of current climate change. A recent paper, studying the consensus regarding the hypothesis that the recent increase in global temperature is predominantly human-made via the emission of greenhouse gasses (see text for reference), argued that the scientific consensus in the peer-reviewed scientific literature pertaining to this hypothesis exceeds 99%. This conclusion was reached after the authors scanned the abstracts and titles of some 3000 papers and mapped them according to their (abstract) statements regarding the above hypothesis. Here, we point out some major flaws in the methodology, analysis, and conclusions of the study. Using the data provided in the study, we show that the 99% consensus, as defined by the authors, is actually an upper limit evaluation because of the large number of “neutral” papers which were counted as pro-consensus in the paper and probably does not reflect the true situation. We further analyze these results by evaluating how so-called “skeptic” papers fit the consensus and find that biases in the literature, which were not accounted for in the aforementioned study, may place the consensus on the low side. Finally, we show that the rating method used in the study suffers from a subjective bias which is reflected in large variations between ratings of the same paper by different raters. All these lead to the conclusion that the conclusions of the study does not follow from the data.
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Measurements of methane and nitrous oxide in human breath and the development of UK scale emissions

by C. Rotter, Dec 16, 2023 in WUWT/PlosOne

In a recent study published in PLOS ONE, titled “Measurements of methane and nitrous oxide in human breath and the development of UK scale emissions,” researchers have embarked on a quest that epitomizes the absurdity of current climate change discourse. This study, focusing on the emissions of methane (CH4) and nitrous oxide (N2O) from human breath, is not only a glaring example of scientific overreach but also a worrying indicator of the lengths to which climate alarmism is willing to go.

The study’s objective to investigate emissions from human breath in the UK population is fundamentally flawed. It operates under the assumption that these emissions are significant enough to warrant detailed analysis and inclusion in national greenhouse gas inventories. This premise is laughable at best, considering the minuscule percentage these emissions contribute to the overall greenhouse gas emissions.

The methodology employed in the study is questionable. Collecting 328 breath samples from 104 volunteers hardly constitutes a representative sample of the UK population. Furthermore, the study’s reliance on such a small sample size to draw conclusions about national-scale emissions is a classic case of over-extrapolation.

The study’s findings that 31% of participants were methane producers and that all participants emitted nitrous oxide are presented without adequate context. These results are portrayed as significant, yet they fail to consider the broader environmental impact. The fact that these emissions are stated contribute a mere 0.05% and 0.1% to the UK’s total emissions of CH4 and N2O, respectively, well below any margin of error in “national inventories” renders these findings insignificant.

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