This paper surveys and interprets the attitudes of scientists to the use of flux adjustments in climate projections with coupled Atmosphere Ocean General Circulation Models. The survey is based largely on the responses of 19 climate modellers to several questions and a discussion document circulated in 1995. We interpret the responses in terms of the following factors: the implicit assumptions which scientists hold about how the environmental policy process deals with scientific uncertainty over human-related global warming; the different scientific styles that exist in climate research; and the influence of organisations, institutions, and policy upon research agendas. We find evidence that scientists' perceptions of the policy process do play a role in shaping their scientific practices. In particular, many of our respondents expressed a preference for keeping discussion of the issue of flux adjustments within the climate modeling community, apparently fearing that climate contrarians would exploit the issue in the public domain. While this may be true, we point to the risk that such an approach may backfire. We also identify assumptions and cultural commitments lying at a deeper level which play at least as important a role as perceptions of the policy process in shaping scientific practices. This leads us to identify two groups of scientists, ‘pragmatists’ and ‘purists’, who have different implicit standards for model adequacy, and correspondingly are or are not willing to use flux adjustments.
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References and Notes
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This was stressed by a number of our respondents. It was also observed by the first author at the IPCC WGI Plenary in Madrid, November 1995.
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An internal report at one Center noted the scale of flux adjustment in an early 1990s coupled model run and commented that it was: ‘Not surprising, since the coarse resolution of the ocean model forces the use of an undesirably large horizontal viscosity in order to achieve computational stability’ (page 1, Murphy, J.: 1991, ‘Transient Response of a Coupled Ocean/Atmosphere Model to a Gradual Increase in CO2’, Hadley Center, Bracknell, U.K., June 1991).
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The only factor which clearly improves at higher resolution is the simulation of regional precipitation, but other factors such as the simulation of diabatic heating and storm tracks do not. Risbey, J. and Stone, P.: 1996, ‘A Case Study of the Adequacy of GCM Simulations for Assessing Regional Climate Changes’, J. Climate 9, 1441–1467.
Relevant here is the changing funding context for research. In many countries, policy-usefulness of knowledge has become more emphasized in the past decade or so. Elzinga, A. and Jamieson, A.: 1995, ‘Changing Policy Agendas in Science and Technology’, in Jasanoff, S., Markle, G., Petersen, J., and Pinch, T. (eds.), Handbook of Science and Technology Studies, Sage, London; Gibbons, M., Limoges, C., Nowotny, H., Schwartzman, S., Scott, P., and Trow, M. (eds.): 1994, The New Production of Knowledge, Sage, London.
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C is surely incorrect to claim that A/O GCMs have little role in the policy debate. A/O GCMs have been used to calibrate the upwelling-diffusion/energy balance model used to make projections in the Second Assessment Report of the IPCC. GCMs also have a wider 'symbolic’ authority. (Shackley, S., Young, P., Parkinson, S., and Wynne, B.: 1998, ‘Uncertainty, Complexity and Concepts of Good Science in Climate Change Modelling: Are GCMs the Best Tools?’, Clim. Change 38, 155–201.)
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Quoted in Ruddock, R.: 1981, ‘Ideologies’, Manchester Monographs 15, Dept. of Adult and Higher Education, Manchester University.
Shackley, S. and Wynne, B.: 1995, ‘Global Climate Change: The Mutual Construction of an Emergent Science-Policy Domain’, Sci. Public Pol. 22(4), 218–230.
Wynne, B.: 1996, ‘SSK's Identity Parade: Signing Up, Off-and-On’, Soc. Stud. Sci. 26, 357–391. We are interested in going beyond the binary assumption that one party is right or wrong, or that someone somewhere can be correct and policy can flow unproblematically from such simple truth (as expressed, for example, in Wildavsky, A.: 1995, But Is It True?, Harvard, Mass., one chapter of which concerned the debate over global warming). The National Research Council report, ‘Understanding Risk’, (op. cit., note 1) provides a useful account of elements of what such an alternative might entail.
Funtowicz, S. and Ravetz, J.: 1993, ‘Science for the Post-Normal Age’, Futures 25, 739–755.
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Shackley, S., Risbey, J., Stone, P. et al. Adjusting to Policy Expectations in Climate Change Modeling. Climatic Change 43, 413–454 (1999). https://doi.org/10.1023/A:1005474102591
- Global Warming
- General Circulation Model
- Policy Process
- Scientific Practice
- Ocean General Circulation Model