There is an old saying, "Your view depends upon your point of view" — a truism that applies to politics as well as scenery. A single set of facts can produce a number of entirely different conclusions. Nowhere is that better demonstrated than in the debate about global warming.
In 1997, after roughly two decades of steadily increasing temperatures, representatives from most of the world's countries met in Kyoto, Japan, to draft what is known as the Kyoto Accord, the first international agreement on the issue of global warming. They were motivated by the fact that temperatures had been rising for about 20 years and computer models were projecting drastic consequences if significant actions were not taken — and soon. The Kyoto Accord set firm and specific targets for reductions in greenhouse gas emissions for most of the developed nations. "Developing nations" — a polite term for poor ones — were excused on the grounds that the economic burden of meeting such targets would make them even poorer; the term included China and India.
During the 15 years since Kyoto, worldwide greenhouse emissions have continued to rise, with China passing the United States as the world's largest source of them. But temperatures have not risen with them. The planet is right about where it was in 1997. The highest recorded temperature year since then was in 2005, with 2007 and 1998 tied for second highest. To have 2012 post temperature numbers lower than those recorded in 1998 hardly represents a steady march toward doom. Even James Hansen, the former NASA scientist who has been the most outspoken activist on the issue, concedes that for 15 years temperatures have been essentially flat, even though worldwide use of fossil fuels has been going up.
What does that mean? Your view depends on your point of view.
From President Obama's point of view as a supporter of global warming theory, the last 15 years have been a temporary aberration. He stresses the fact that "12 of the last 15 years have been the warmest on record," suggesting that the future trend will again turn upward and prove him right. From the point of view of global warming sceptics, the past 15 years are the future trend and they've already been proven right.
My point of view, growing out of conversations I have had with scientists at various national laboratories, is that both of these conclusions are premature. The climate is far too complex to be captured by the models that have been built, and more study — a lot more — is needed before we can be even relatively sure about what the future may hold. No single 15- or even 20-year period can be a reliable indicator of a long-term climate trend.
One scientist told me, "There are at least six different indicators of climate behavior and we have only studied two of them — temperature and the acidity of the oceans. We think we have enough evidence from those two areas to conclude that human activity is affecting the climate in a major way, but we cannot be sure exactly how or how much. There could be other forces at work here that we still don't understand."22 comments on this story
He summarized by saying: "The science is not settled."
That suggests that more research is clearly in order, but that panic is not. I agree with another scientist who, when asked what he thought we should be doing, given all the uncertainties that surround the issue, told me, "We should be doing things that make sense anyway."
That makes sense from any point of view.
Robert Bennett, former U.S. Senator from Utah, is a part-time teacher, researcher and lecturer at the University of Utah's Hinckley Institute of Politics.