Surveys of scientists' views on climate change

Surveys of scientists' views on climate change – with a focus on human-caused or anthropogenic global warming (AGW) – have been undertaken since the 1990s. A 2016 paper (which was co-authored by Naomi Oreskes, Peter Doran, William Anderegg, Bart Verheggen, Ed Maibach, J. Stuart Carlton and John Cook, and which was based on a half a dozen independent studies by the authors) concluded that "the finding of 97% consensus [that humans are causing recent global warming] in published climate research is robust and consistent with other surveys of climate scientists and peer-reviewed studies." A 2019 study found scientific consensus to be at 100%, and a 2021 study found that consensus exceeded 99%. Krista Myers led a paper which surveyed 2780 Earth scientists. Depending on expertise, between 91% (all scientists) to 100% (climate scientists with high levels of expertise, 20+ papers published) agreed human activity is causing climate change. Among the total group of climate scientists, 98.7% agreed. The agreement was lowest among scientists who chose Economic Geology as one of their fields of research (84%). In 2021, Mark Lynas et al assessed studies published between 2012 and 2020. They found over 80,000 studies. They analysed a random subset of 3000. Four of these were skeptical of the human cause of climate change, 845 were endorsing the human cause perspective at different levels, and 1869 were indifferent to the question. The authors estimated the proportion of papers not skeptical of the human cause as 99.85% (95% confidence limit 99.62%–99.96%). Excluding papers which took no position on the human cause led to an estimate of the proportion of consensus papers as 99.53% (95% confidence limit 98.80%–99.87%). They confirmed their numbers by explicitly looking for alternative hypotheses in the entire dataset, which resulted in 28 papers. In 2019, James L. Powell, a former member of the National Science Board, analysed titles of peer-reviewed studies published in the first seven months of 2019 and found not a single study disagreed with the consensus view.