The consensus that humans are causing recent global warming is shared by
90%–100% of publishing climate scientists according to six independent
studies by co-authors of this paper. Those results are consistent with
the 97% consensus reported by Cook et al (Environ. Res. Lett.
8 024024) based on 11 944 abstracts of research papers, of
which 4014 took a position on the cause of recent global warming. A
survey of authors of those papers (N = 2412 papers) also supported a 97% consensus. Tol (2016 Environ. Res. Lett.
11 048001) comes to a different conclusion using results from
surveys of non-experts such as economic geologists and a self-selected
group of those who reject the consensus. We demonstrate that this
outcome is not unexpected because the level of consensus correlates with
expertise in climate science. At one point, Tol also reduces the
apparent consensus by assuming that abstracts that do not explicitly
state the cause of global warming ('no position') represent
non-endorsement, an approach that if applied elsewhere would reject
consensus on well-established theories such as plate tectonics. We
examine the available studies and conclude that the finding of 97%
consensus in published climate research is robust and consistent with
other surveys of climate scientists and peer-reviewed studies.
- anthropogenic global warming
- climate change
- scientific consensus