Proof of global warming as good as science can get—its time for action

When Al Gore was awarded a Nobel Peace Prize for his environmental activism against global warming, the most immediate consequence was an increase in the temperature of the debate over climate change. Columnists and pundits denounced the decision as a politically motivated. Thousands of university faculty and professional scientists around the country have received petitions asking them to denounce the science of global warming and the political steps needed to address it.

The publicity poster for Gore’s film An Inconvenient Truth depicts smokestacks spewing exhaust that ominously rises into the air to form a great hurricane cloud. The implication is obvious: our use of fossil fuels is altering the climate and spawning negative repercussions such as destructive hurricanes like Katrina. But what is wrong with this picture? It turns out that the hurricane cloud is wrong—it is spinning clockwise while Katrina, like all hurricanes in the Northern Hemisphere, spun in the opposite direction. Is that symbolic of what critics of global warming suggest—folks like Al Gore have their science backward? Is it true that the science surrounding global warming is inconclusive?

Those who understand the nature of science know that in some respects, no science is ever completely conclusive. Science is unable to offer absolute proof of any proposition, but it can yield levels of confidence. The Intergovernmental Panel on Climate Change (IPCC) received the Nobel Prize along with Gore. Being a collection of the world’s foremost climate scientists, the IPCC framed their conclusions in probabilistic terms. The IPCC concluded that “climate change is unequivocal,” and that they are over 90 percent confident that most of the change is due to human activity. They place the probability that natural factors could account for the observed changes at less than 5 percent. This is in fact an underestimate of the confidence felt by most IPCC scientists, since their document was a consensus report with compromise language needed to get general agreement.

Yes, you can find many global warming skeptics, and many of them have Ph.D.s. There are even a very few contrarian climate scientists who have received significant publicity. But because science cannot offer absolute proof, you can have tobacco scientists denying the link between cancer and smoking 30 years after the connection was clear to unbiased scientists. The Vatican refused to recant their condemnation of Galileo’s argument that the earth circled the sun for 300 years.

Unfortunately, we do not have 300, or even 30, years to wait. Exactly half a world away from New Orleans lies the country of Bangladesh. Like its North American counterpart, Bangladesh is a low-lying country susceptible to severe storms and flooding. Unlike New Orleans, it has a population of 150 million poor people who have suffered homelessness and fatalities from cyclones and flooding many times greater than what was suffered in America. Even small changes in sea level, precipitation patterns and Himalayan snow-pack associated with climate change will result in human devastation many times greater than Katrina’s.

Arguments about global warming are indeed, as Al Gore emphasized, a truly moral issue. If we wait for scientific “proof” before we take the steps necessary to address global warming, we condemn the millions of Bangladesh, and the millions of others dependent upon our current climate, to almost certain suffering.

Wendell Berry, the Christian essayist who farms in Kentucky without fossil fuel, captures the crux of the issue well: “The great obstacle is simply this: the conviction that we cannot change because we are dependent upon what is wrong. But that is the addict’s excuse, and we know that it will not do.” Commit to individual change now, and demand that those with the power to affect lives other than their own commit to change, as well.

Michael Kunz is AIMS professor of science and directs the environmental science and environmental studies programs in the Fresno Pacific University School of Natural Science. AIMS is the Activities Integrating Mathematics and Science Education Foundation.