Speaker John Boehner has made some encouraging statements since the election, pointing toward productive policy-making. This was not one of them:
I dont think theres any doubt that weve had climate change over the last 100 years, he told USA Today. What has initiated it, though, has sparked a debate thats gone on now for the last 10 years.
I dont think were any closer to the answer than we were 10 years ago.
President Obama recently sounded some positive notes on climate change. His comments rekindled hopes of environmentalists that his second term will see more aggressive policymaking to combat global warming than did his first. Boehners words, which appear to mischaracterize the scientific debate on global warming, indicate that blinkered Republican opposition to doing much of anything about the problem may persist.
Climate science is complicated, but the basic physical principles on which the scientific consensus is based are not. Gases such as carbon dioxide trap the energy that pours down on the Earth from the sun, making the Earth habitable. Since the middle of the 20th century, scientists have studied the effects of adding large amounts of additional heat-trapping gases to the atmosphere, and they have made great progress in describing how and why the world is warming, and how that trend is likely to play out.
Scientists use real-world observations to describe the climates past. Then they build complex models that reflect those and other observations and run them on supercomputers. After decades of this, nearly every expert agrees that global warming is a problem. The biggest question now is not whether human-produced greenhouse emissions have an effect but how significant that effect will be.
In Boehners last 10 years alone, the models and the quality of the information that feeds into them have gotten progressively better. The journal Science recently published a study from two climate researchers at the National Center for Atmospheric Research that addresses the behavior of clouds in different climate models, one of the primary sources of continuing uncertainty about how sensitive the climate will be to increased levels of carbon dioxide. Using satellite measurements of relative humidity, they determined that the models that predict relatively modest warming did not reflect the satellite record as well as those predicting much more alarming outcomes. In other words, the more pessimistic models are likely to be more accurate.
Predictions about the future climate must be tempered by an appreciation of the uncertainties inherent to describing extremely complicated earth systems. But the risks of global warming that decades of science describe are clearly great enough to warrant action.
Boehners office said the speaker was talking about the stagnation of the policy debate over the past 10 years, not the state of the science. If thats the case, then he should be willing to stand up for the climate researchers and push Washingtons policy deliberations into accord with the science.