The temperature of the troposphere above the tropics has changed little.
Climate change is one of the most complex topics in science. New insights arise every month. Key discoveries are anticipated in the next few years. Yet politicians seem to think we've learned everything there is to know about the climate. And they keep designing static policy plans based on that assumption.
We have seen the failure of this approach with the Kyoto Protocol. So as world leaders meet in Bali, Indonesia, this week to discuss a replacement treaty, they should keep this simple principle in mind: Good climate policy must be dynamic, not static, and this requires incorporating a learning process.
Politicians like long-term commitments because they can push costs into the future. But long-term commitments are foolish when you are still awaiting key information about the nature of the problem.
For instance, scientists from nine countriesare conducting experiments in Switzerland to test the influence of the sun's magnetic field on our climate. There is evidence that the constant shower of cosmic rays from space enhances cloud formation. The sun's magnetic field partly shields the Earth from cosmic rays. Research suggests that the sun's magnetic field has strengthened since 1900, weakening the cosmic-ray flow and reducing average cloud cover – which allows temperatures to rise. The experiments could show that the sun, not greenhouse gases, explains most global warming. Results are expected as early as 2010.
Or consider the tropical troposphere, the vast atmospheric region centered about 10 miles above the earth, ringing the equator. Climate models project that, if carbon emissions cause warming, the strongest effect will be up there. But both the Intergovernmental Panel on Climate Change and the US Climate Change Science Program (CCSP) have found no significant warming there. A 2006 CCSP report called this a "potentially serious inconsistency" and pointed out that the models with the best fit to the data show low amounts of greenhouse warming. If warming in the tropical troposphere is not soon observed, it will convincingly refute the standard greenhouse warming model.
The bottom line is that, over the next few years, we will acquire new information that might overturn current beliefs about greenhouse warming. To lock into a policy path that ignores future information makes no sense.