A new study published in the journal Climate by a group of researchers from various universities and research institutes in Israel (Dentelski, et al.) debunks a study in another journal that claimed support for the theory humans are causing dangerous climate change “anthropogenic global warming” (AGW) tops 99 percent.

A 2021 study (Lynas et al.) claimed a review of a random sample of 3,000 publications discussing climate change, out of “a dataset of 88125 climate-related papers published since 2012,” found fewer than one percent, four or 28 depending upon the methodology used to identify the papers, disputed that humans were causing climate change.

Ignoring the fact consensus is a political exercise to establish strong agreement on a goal, not a scientific method to establish facts or truth, numerous scholars have refuted previous claims of a purported 97 percent consensus “established” using similar methodologies—examining abstracts and then subjectively categorizing them into consensus or skeptical. Indeed, international surveys of scientists working in climate-related fields have repeatedly shown that no such consensus exists.

The new Dentelski et al. study examining the methodology and conclusions of the Lynas et al. paper claiming a 99 percent consensus supporting the AGU theory finds the methodology used in the 2-21 paper is flawed and biased, and its conclusion unjustified.

Describing why it is important to carefully analyze any assertion that an irrefutable AGU consensus exists, the Israeli scholars write:

The extent of the consensus among scientists on the anthropogenic origin of modern global warming has become a key issue in the “anthropogenic global warming” … While a consensus alone clearly does not serve as scientific proof or substantiate a specific scientific hypothesis, it is nonetheless influential in bolstering the reception of a particular thesis within the broader public sphere. This influence is amplified by the inherent trust that society places in scientists, who provide informed opinions grounded in empirical evidence. … The well-defined scientific hypothesis that “humans, through the emission of CO2, are responsible for most of the recent (since the mid-20th century) changes in global average temperature” (dubbed the AGW hypothesis hereafter) is typically linked with various, somewhat less quantifiable, statements, such as that humanity is facing an imminent climate crisis, and are followed by calls for action on individual, community, country, and global levels.

The Climate paper points out that the 2021 paper was flawed from the outset because its authors failed to precisely define the AGU hypothesis they claimed represented a consensus.

“By blurring the hypothesis, Lynas et al. leave room for a subjective decision on supporting some version of the hypothesis,” write Dentelski et al. “[Yet because] consensus, in the context of the climate discussion, can mean different things and has different dimensions … within each dimension, the specific consensus statement must be as specific, and quantitative, as possible.”

Starting from an ill-defined, vague notion of the AGU hypothesis being tested for consensus, Lynas et al.’s paper then examined the abstracts of 3,000 climate-change-related papers out of more than 88,000 published since 2012, sorting them into categories: (1) explicit quantitative support of the AGW hypothesis, (2) explicit non-quantitative support, (3) implicit support, (4) no position or uncertainty, (5) an implicit rejection of the AGW hypothesis, (6) explicit rejection without quantification, and (7) an explicit quantitative rejection.

It turns out that by their own standards, more than two-thirds of the papers they analyzed either took no position or there was uncertainty about their position. So, what did Lynas and his colleagues do? After tossing 282 papers as not being climate-related, after all, they counted the remaining neutral and uncertain papers as accepting the AGU hypothesis. Voila, you have a 99 percent consensus.

As Dentelski and his colleagues point out, one could just as easily have counted the neutral/uncertain category papers as skeptical and, as a result, concluded that just 32 percent of the published research supported the AGU hypothesis, however defined.

Adding insult to injury (to the scientific method and logic), Dentelski et al. found a number of papers categorized as neutral were actually disputing or proposing alternative explanations for measured and modeled warming, like papers from Soon et al. In the end, the new paper in Climate shows that absent a clearer definition of AGU to be tested for consensus and a more accurate methodology in treating papers, there is no justification for the claim there is a 99 percent (or 97 percent) consensus humans are causing dangerous climate change in the published literature.

This piece was originally published by HeartlandDailyNews and has been republished here with permission.