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According to a survey of 88.125 climate-related studies, more than 99.9% agree with climate change being caused primarily by humans.
This research is an update to a 2013 paper. It revealed that 97% of studies published in the period 1991-2012 supported the notion that human activities are changing Earth's climate. To see if the consensus has changed, the current survey reviews the literature from 2012 to 2020.
"We are almost certain that the consensus now is well above 99% and that it's pretty much closed for any meaningful public discussion about the reality of human-caused global warming," stated Mark Lynas (a visiting fellow at Cornell University's Alliance for Science and the paper’s first author).
"It is critical to recognize the primary role of greenhouse gas emission so that we can quickly mobilize new solutions," stated Benjamin Houlton of Cornell's College of Agriculture and Life Sciences. He was also a coauthor of the study "Greater Than 99% Consensus On Human Caused Climate Change In the Peer-Reviewed Scientific Literature," published in Environmental Research Letters, Oct. 19.
These results are not supported by public opinion polls or the opinions of politicians and representatives. They also point out false beliefs and claim that there is still a substantial debate among scientists about the cause of climate change. According to Pew Research Center, only 27% believed that climate change was caused by human activity in 2016. Gallup's 2021 poll revealed a widening partisan divide in American politics over whether the Earth's increasing temperatures since the Industrial Revolution was primarily due to humans.
Lynas stated that to understand the consensus, one must be able quantify it. To avoid cherry-picking papers and trading them, it is important to examine the literature in a cohesive and non-arbitrary manner.
The researchers started by looking at a random selection of 3,000 papers from the 88,125 English language climate papers published between 2012-2020. Only four of the 3,000 papers they examined were skeptical that human-caused climate changes are occurring. Lynas stated that although we knew climate skeptical papers were rare, they believed there must have been more than 88,000.
Simon Perry, a UK-based software engineer who volunteers at the Alliance for Science, was co-author. He created an algorithm that searches for keywords in papers they know are skeptical. The algorithm was applied across all 88,000 papers. The program ranked the skeptical papers higher so that the algorithm could be used again. As expected, they found many of these dissident papers at the top of the list, with decreasing returns further down. The search resulted in 28 papers that were either implicitly or explicitly skeptical. All of these papers were published in minor journals.
Lynas stated that although the 2013 study's 97% results still raise doubts about scientific consensus regarding human impact on climate, the new findings are more convincing and will eliminate any uncertainties. He said, "This pretty much should stand as the final word."
Continue reading. Explaining the scientific consensus might help convince naysayers
More information: Environmental Research Letters, Greater than 99% Consensus On Human Caused Climate Change in Peer-Reviewed Scientific Literature (2021). Information for Journal: Environmental Research Letters, Greater Than 99% Consensus On Human Caused Climate Change In the Peer-Reviewed Scientific Literature (2021). DOI: 10.1088/1748-9326/ac2966