Science never writes closed textbooks. It does not offer us a holy scripture, infallible and complete.
I am a climate scientist who worked in the Climatic Research Unit (CRU) at the University of East Anglia in the 1990s. I have been reflecting on the bigger lessons to be learned from the stolen emails, some of which were mine. One thing the episode has made clear is that it has become difficult to disentangle political arguments about climate policies from scientific arguments about the evidence for man-made climate change and the confidence placed in predictions of future change. The quality of both political debate and scientific practice suffers as a consequence.
Surveys of public opinion on both sides of the Atlantic about man-made climate change continue to tell us something politicians know only too well: The citizens they rule over have minds of their own. In the U.K., a recent survey suggested that only 41% believed humans are causing climate change, 32% remained unsure and 15% were convinced we aren't. Similar surveys in the U.S. have shown a recent reduction in the number of people believing in man-made climate change.
One reaction to this "unreasonableness" is to get scientists to speak louder, more often, or more dramatically about climate change. Another reaction from government bodies and interest groups is to use ever-more-emotional campaigning. Thus both the U.K. government's recent "bedtime stories" adverts, and Plane Stupid's Internet campaign showing polar bears falling past twin towers, have attracted widespread criticism for being too provocative and scary. These instinctive reactions fail to place the various aspects of our knowledge about climate change—scientific insights, political values, cultural moods, personal beliefs—in right relationship with each other. Too often, when we think we are arguing over scientific evidence for climate change, we are in fact disagreeing about our different political preferences, ethical principles and value systems.
If we build the foundations of our climate-change policies so confidently and so single-mindedly on scientific claims about what the future holds and what therefore "has to be done," then science will inevitably become the field on which political battles are waged. The mantra becomes: Get the science right, reduce the scientific uncertainties, compel everyone to believe it. . . and we will have won. Not only is this an unrealistic view about how policy gets made, it also places much too great a burden on science, certainly on climate science with all of its struggles with complexity, contingency and uncertainty.
The events of the last few of weeks, involving stolen professional correspondence between a small number of leading climate scientists—so-called climategate—demonstrate my point. Both the theft itself and the alleged contents of some of the stolen emails reveal the strong polarization and intense antagonism now found in some areas of climate science.
Climate scientists, knowingly or not, become proxies for political battles. The consequence is that science, as a form of open and critical enquiry, deteriorates while the more appropriate forums for ideological battles are ignored.
We have also seen how this plays out in public debate. In the wake of climategate, questions were asked on the BBC's Question Time last week about whether or not global warming was a scam. The absolutist claims of two of the panelists—Daily Mail journalist Melanie Phillips, and comedian and broadcaster Marcus Brigstocke—revealed how science ends up being portrayed as a fight between two dogmas: Either the evidence for man-made climate change is all fake, or else we are so sure we know how the planet works that we can claim to have just five or whatever years to save it. When science is invoked to support such dogmatic assertions, the essential character of scientific knowledge is lost—knowledge that results from open, always questioning, enquiry that, at best, can offer varying levels of confidence for pronouncements about how the world is, or may become.
The problem then with getting our relationship with science wrong is simple: We expect too much certainty, and hence clarity, about what should be done. Consequently, we fail to engage in honest and robust argument about our competing political visions and ethical values.
Science never writes closed textbooks. It does not offer us a holy scripture, infallible and complete. This is especially the case with the science of climate, a complex system of enormous scale, at every turn influenced by human contingencies. Yes, science has clearly revealed that humans are influencing global climate and will continue to do so, but we don't know the full scale of the risks involved, nor how rapidly they will evolve, nor indeed—with clear insight—the relative roles of all the forcing agents involved at different scales.
Similarly, we endow analyses about the economics of climate change with too much scientific authority. Yes, we know there is a cascade of costs involved in mitigating, adapting to or ignoring climate change, but many of these costs are heavily influenced by ethical judgements about how we value things, now and in the future. These are judgments that science cannot prescribe.
The central battlegrounds on which we need to fight out the policy implications of climate change concern matters of risk management, of valuation, and political ideology. We must move the locus of public argumentation here not because the science has somehow been "done" or "is settled"; science will never be either of these things, although it can offer powerful forms of knowledge not available in other ways. It is a false hope to expect science to dispel the fog of uncertainty so that it finally becomes clear exactly what the future holds and what role humans have in causing it. This is one reason why British columnist George Monbiot wrote about climategate, "I have seldom felt so alone." By staking his position on "the science," he feels alone and betrayed when some aspect of the science is undermined.
If climategate leads to greater openness and transparency in climate science, and makes it less partisan, it will have done a good thing. It will enable science to function in the effective way it must do in public policy deliberations: Not as the place where we import all of our legitimate disagreements, but one powerful way of offering insight about how the world works and the potential consequences of different policy choices. The important arguments about political beliefs and ethical values can then take place in open and free democracies, in those public spaces we have created for political argumentation.
Mr. Hulme, author of "Why We Disagree About Climate Change," is professor of climate change at the University of East Anglia.