On the pressures of policy-relevant climate science
Without any “evidence of fraud, malfeasance or deliberate deception or manipulation,” or any promotion of inaccurate views, how can bias enter a scientific assessment? In their new book, Discerning Experts, Michael Oppenheimer, Naomi Oreskes, Dale Jamieson, et al explore the pattern of underestimation of the true consequences of climate change.
Climate change's impacts are uncertain; predictions about climate change are difficult to make. Taking an ethnographic approach, Discerning Experts shows how those difficulties, coupled with the nature of the public discourse, and the pressures that come when research is going to be discussed and used in policy, have tilted climate assessment optimistic and cautious.
In a summary of their book, Oreskes et al explain three reasons for the tilt:
“The combination of … three factors—the push for univocality, the belief that conservatism is socially and politically protective, and the reluctance to make estimates at all when the available data are contradictory—can lead to ‘least common denominator' results—minimalist conclusions that are weak or incomplete.”
These tendencies, according to the authors, pertain to the applied research context. The academic context is different: “The reward structure of academic life leans toward criticism and dissent; the demands of assessment push toward agreement.” Link to a summary essay in Scientific American. Link to the book.
- In an interview, Michael Oppenheimer elaborates on other elements that skew the assessments: the selection of authors, the presentation of the resulting information, and others. Link.
- In a review of the book, Gary Yohe reflects on his own experience working on major climate assessments, such the IPCC’s. Link.
- A David Roberts post from 2018 finds another case of overly cautious climate science: models of the economic effects of climate change may be much more moderate than models of the physical effects. To remedy this, “We need models that negatively weigh uncertainty, properly account for tipping points, incorporate more robust and current technology cost data, better differentiate sectors outside electricity, rigorously price energy efficiency, and include the social and health benefits of decarbonization.” Link.
- Tangentially related: carbon tax or green investment? It’s worth considering not just all possible policy options but also their optimal interactions. A paper by Julie Rozenberg, Adrien Vogt-Schilb, and Stephane Hallegatte concludes, “Optimal carbon price minimizes the discounted social cost of the transition to clean capital, but imposes immediate private costs that disproportionately affect the current owners of polluting capital, in particular in the form of stranded assets.” Link to a summary which contains a link to the unpaywalled paper.