Climate Models and Their Critics

t is getting more and more difficult to have a public conversation about global climate change. The vast majority of climate scientists believes human-made greenhouse gases, especially carbon dioxide from combustion, are increasing global temperatures and destabilizing the climate (page 23). The view is backed by the world’s leading research agencies, including America’s National Academy of Sciences, and seconded by scientific organizations as diverse as the American Association for the Advancement of Science (AAAS), American Geophysical Union, and the American Statistical Association. Yet climatology is a young science. Its practitioners rarely work in laboratories. They must rely on highly variable field measurements and complex mathematical models that have very visible limitations. Arrayed against them are a smaller number of scientists and engineers. Only some have degrees in climate-related sciences. They charge that governments and climate activists have a pro-global warming agenda that stifles true scientific debate and that climate data and models are flawed. Many of these so-called skeptics have a clear agenda. They seem bent on denying climate change at any cost. Few do original research or publish in peer-reviewed climate journals (some submit articles to friendly journals in unrelated fields). Nor do they propose research to resolve the contradictions they claim to find, a common practice among the climate scientists whom they also claim lack skepticism. It is a recipe for controversy. And on the Internet, these scientific debates take on a life of their own.