A new survey of 88,125 climate-related studies has revealed that over 99.9% of peer-reviewed scientific papers concur that humans are the major cause of climate change.
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The study gives an update on a similar 2013 paper showing that 97% of studies reported between 1991 and 2012 endorsed the concept that human activities are responsible for changing the Earth’s climate. The present survey analyzes the literature reported from 2012 to November 2020 to see if there is any change in the consensus.
We are virtually certain that the consensus is well over 99% now and that it’s pretty much case closed for any meaningful public conversation about the reality of human-caused climate change.
Mark Lynas, Study First Author and Visiting Fellow at the Alliance for Science, Cornell University
“It’s critical to acknowledge the principal role of greenhouse gas emissions so that we can rapidly mobilize new solutions, since we are already witnessing in real time the devastating impacts of climate related disasters on businesses, people and the economy,” stated Benjamin Houlton, the Ronald P. Lynch Dean of the College of Agriculture and Life Sciences and a co-author of the study.
The study titled “Greater than 99% Consensus on Human Caused Climate Change in the Peer-Reviewed Scientific Literature” was reported in the Environmental Research Letters journal on October 19th, 2021.
Despite obtaining such results, public opinion polls and opinions of politicians and public representatives point to incorrect beliefs and claims that a major debate still prevails among researchers over the real cause of climate change.
According to the study, in 2016, the Pew Research Center had discovered that only 27% of U.S. adults think that “almost all” researchers agreed that climate change is caused as a result of human activity.
A 2021 Gallup poll indicated a widening partisan divide in American politics on whether Earth’s increasing temperatures from the Industrial Revolution were mainly caused by humans.
To understand where a consensus exists, you have to be able to quantify it. That means surveying the literature in a coherent and non-arbitrary way in order to avoid trading cherry-picked papers, which is often how these arguments are carried out in the public sphere.
Mark Lynas, Study First Author and Visiting Fellow at the Alliance for Science, Cornell University
As part of the study, the team started by analyzing a random sample of 3,000 studies obtained from the dataset of 88,125 English-language climate papers reported between 2012 and 2020. They were able to find only four out of the 3,000 papers were doubtful of human-caused climate change.
We knew that [climate skeptical papers] were vanishingly small in terms of their occurrence, but we thought there still must be more in the 88,000.
Mark Lynas, Study First Author and Visiting Fellow at the Alliance for Science, Cornell University
The co-author of the study Simon Perry, a UK-based software engineer and volunteer at the Alliance for Science, made an algorithm that identified keywords from papers the team knew were skeptical, like “cosmic rays,” “solar” and “natural cycles.”
The researchers applied the algorithm to all 88,000-plus papers, and the program arranged them such that the skeptical ones stood higher in the order. They discovered many of such dissenting papers near the top, as anticipated, with declining returns further down the list. On the whole, 28 papers were found to be implicitly or explicitly skeptical. However, all were published in minor journals.
According to Lynas, if the 97% results obtained from the 2013 study still left a few questions on the scientific consensus on the human impact on climate, the present findings go a lot further to ease any uncertainty.
Lynas stated, “This pretty much should be the last word.”
Financial support for the Alliance for Science was offered by the Bill and Melinda Gates Foundation.
Journal Reference:
Lynas, M., et al. (2021) Greater than 99% consensus on human caused climate change in the peer-reviewed scientific literature. Environmental Research Letters. doi.org/10.1088/1748-9326/ac2966.