Climate Change Modeling: Science vs. Skepticism Debate

Introduction: Consensus and Skepticism in Climate Science

Since the release of the IPCC report on climate change, a growing consensus has emerged within the scientific community that the effects of global warming are real and that there is a significantly high degree of certainty those effects can be traced back to anthropogenic causes. Yet despite this mounting consensus, there remain very vocal critics of global warming science — so-called climate change skeptics. Derided by environmentalists as shills for corporate interests and the fossil fuel industry, the skeptics are nonetheless well organized and well informed. Their arguments are placed side-by-side with those of noted climate change scientists in the media, usually on a one-to-one basis, giving the public the impression that the scientific community is literally split down the middle on the issue of climate change and its causes.

While it is certainly not my intention to feed into the erroneous assumption that denies the growing scientific consensus on climate change, it is important that we at least consider the arguments and positions of climate change skeptics. After all, science is not run by consensus or by vote. If that were the case, many of the greatest discoveries in the history of science would never have occurred because mainstream science rejected those claims. At the same time, we must be careful not to give too much credence to the scientific underdog simply because he is the underdog. Science moves forward on the basis of falsifiable hypotheses. This is the measure by which we must judge scientists and their theories — both those who conclude anthropogenic climate change is real and those who are skeptical of such conclusions.

The purpose of this paper is to analyze the positions of two researchers who hold opposing views on climate change. Specifically, I will consider their positions in light of several significant differences, primarily on the issue of computer modeling. The first is S. Fred Singer, an atmospheric physicist who argues that "the scenarios are alarmist, computer models reflect real gaps in climate knowledge, and future warming will be inconsequential or modest at most" (Singer). On the other side is Tom Wigley, a climatologist and senior scientist at the National Center for Atmospheric Research who draws on a wide array of evidence to support his claims regarding climate change. I will consider the position of each on the issues of computer modeling and the potential impact of climate change, drawing on outside research to demonstrate which position has the greater likelihood of being correct.

The Role of Computer Modeling in Climate Science

The first issue to consider is computer modeling, which most climate change scientists must regularly rely on in order to make useful sense of the potential long-term impacts of recent changes in the Earth's climate system. Wigley points out that climate models are not unlike weather models, except that they operate on much longer time scales. In other words, the models will not tell you what will happen with certainty, but rather what is the most probable outcome based on all available data (Wigley). This is why weather forecasters say there is a 40% chance of snow tomorrow afternoon, rather than declaring it an absolute certainty that exactly 2.3 inches of snow will fall between 2:30 p.m. and 3:15 p.m.

Singer's Critique of Model Reliability

The issue is that when we are dealing with models that work on systemic averages, a certain degree of uncertainty and ambiguity is built into the model itself. Climate change skeptics like Singer immediately prey upon this uncertainty. He argues that the models are too ambiguous and seemingly contradictory to warrant our confidence. Different models produced by different scientists to account for different data sets cannot necessarily agree with one another, and therefore the models cannot be trusted. Singer even goes so far as to imply that we cannot trust the scientists who construct these models, suggesting they could tweak the models to produce the results they want — apparently in order to impress their colleagues and ensure funding for future projects (Singer). Such a claim borders on slanderous and cannot rightfully be counted as a mark in favor of Singer's position. Wigley responds plainly: "Cooking the books would be a concern if that was what scientists were apt to do. But I don't think scientists generally behave that way" (Wigley). Indeed, if we accept that scientists will do anything to secure their next paycheck, then the integrity of the scientific process is lost — and the claims of all scientists, Singer included, cannot be trusted.

Singer does, however, place specific emphasis on the apparent inability of climate models to account for data already collected, most notably from weather satellites, in which he places greater faith. For example, global temperatures appear to have warmed from 1900 to 1940, cooled from then until 1975, warmed again from 1975 to 1979, and then cooled once more through at least the end of the twentieth century (Singer). Superficially, this pattern seems inconsistent with the models' basic premise that human activity has been driving climate change. If that were the case, shouldn't increased human activity over the past century have produced relatively linear increases in global temperatures?

To that charge, Wigley has a direct response. He notes that even this variability can be consistent with the climate models, especially when we consider the nature of human activity over that period. He contends that modeling climate change is far more complex than expecting a one-to-one ratio based on a single causative factor, as Singer implies. Instead, even human activity produces elements that will both exacerbate and counteract any warming trend.

Conclusion: Evaluating the Two Positions

In the final analysis, the division between these two scientists is extreme. But, as should be apparent from this discussion, the position that Wigley takes is much more rational and better informed by the available data than Singer's. Singer is content to repeatedly point out that the models being used are not accurate enough, even as mounting evidence confirms that the models are performing correctly. Beyond that, he argues that even if climate change is occurring, it will certainly be beneficial for civilization. Skepticism is an important part of the scientific process, but Wigley's position is not one of absolutes. His role is to report the available evidence and explain how existing models account for that evidence. The IPCC's broader scientific framework, alongside the studies examined here, supports this evidence-based approach. Based on the interviews analyzed, Wigley's stance is a far more rational and reasonable one — and it affords him a clear edge in this analysis.