The Heartland Institute, a Chicago-based think tank, recently hosted a conference on climate change. Heartland can be fairly described as sceptical of the idea that global warming is primarily man-made, or that if occurring it represents a serious problem. However, the organizers were keen to include representatives of all sides of the debate. Invitations were therefore extended to global warming sceptics such as Harvard’s Willie Soon and MIT’s Richard Lindzen- but also prominent scientific supporters of the International Panel on Climate Change (IPCC) view that manmade global warming is a serious threat.
Unfortunately, the conference did not work out as planned. Out of the dozens of supporters of the IPCC’s conclusions that were invited, only two were willing to attend. The result was an informative and fascinating but unbalanced conference. One sceptic after another took the stage and showed how their research casts doubt on catastrophic predictions, with few defenders of the IPCC position present to provide a critique. The organizer of the program was disappointed, and apologized to the audience for the fact that more supporters of the IPCC view had declined his invitation.
The conference was still useful, in that it gave the lie to the claim that the “debate is over” surrounding the science of global warming. The conference featured a world-famous astrophysicist explaining his opinion that solar activity has caused recent increases in temperature. It also included an MIT atmospheric physicist who argued the sensitivity of temperature to atmospheric greenhouse gas concentrations is badly overestimated by the IPCC. These were just two of many impressive presentations . One can’t listen with an open mind to this parade of experts who dispute the IPCC’s conclusions and still take seriously the claims that the “debate is over.”
And yet, while the presentations were informative, it was impossible to accurately assess the strength of the evidence due to the absence of competing points of view. The strength of arguments in technical areas are best evaluated under pressure. It is important to see experts who disagree analyze one another’s work, and clearly state why they remain unconvinced by the conclusions. With no similarly qualified experts willing to debate with Soon, Lindzen, and the other sceptical experts, it was impossible to assess which side has the strongest arguments.
So why wouldn’t the defenders of the majority opinion that manmade global warming is a threat show up to debate the dissenters? Perhaps some feared they would be treated badly or unfairly- if so, these fears were unfounded. The two supporters of the IPCC view who did attend were treated warmly, and thanked repeatedly for creating a small measure of balance.
It seems likely the refusal of most IPCC supporters to attend was the result of a conscious decision taken some time ago not to engage people who are sneeringly referred to as “deniers.” Because it is less likely that political action will be taken as long as it is known there is a lively scientific debate, prominent environmental activists have argued that “deniers” should simply be ignored and marginalized, regardless of their credentials or the quality of their work.
The clearest example is the refusal of Al Gore –the man who popularized the most catastrophic theories about global warming- to even debate the topic. Imagine if the leading proponents of tax cuts refused to debate Keynesian advocates because the “economics are settled.” They’d be laughed out of the public sphere- and deservedly so.
The strategy of refusing to engage dissenters has been unsuccessful. Public perception of the issue is shifting in the direction of the sceptics. In December 2009, just 52 per cent of Canadians said that they are convinced that global warming is a man-made phenomenon- down from a peak in the mid-60s. In the United States, belief in man-made warming dropped from 51 per cent to 46 per cent in the second half of 2009. Gore’s strategy of disengagement has apparently backfired.
By refusing to confront their critics head-on, the majority of climate scientists give the appearance they are afraid of debate. That leads many to conclude their case is weak. Proponents of the IPCC should abandon the strategy of marginalizing dissenters and calling them names. Instead, if they really believe the facts are on their side, they need to actually engage those who think otherwise. Until then, public skepticism will continue to grow towards a political and scientific community that consistently hides from its brightest, most articulate critics.