On December 19th the Environmental Protection Agency (EPA) rejected proposals from Oregon, California and 15 other states to impose new regulations on motor vehicles for the purpose of reducing carbon dioxide and other so-called “greenhouse gases” (GHG). Predictably, this brought forth howls of protest from grandstanding politicians. Richard Blumenthal, the attorney general of Connecticut, called the ruling “outrageous.” California Senator Dianne Feinstein said, “I find this disgraceful.” Oregon Governor Ted Kulongoski promised to use “any legal means necessary to make sure Oregon can set its own tailpipe emissions standards.”
If these people had taken as much time studying air pollution trends as they did preparing for lawsuits, they would know that their statements are absurd.Clean-up of pollution from motor vehicles has been one of the great American success stories in modern times, and the success will continue for decades due to technological innovation and auto fleet turnover. Litigation regarding carbon dioxide emissions is unnecessary and will just be an expensive sideshow.
Here are the facts. Between 1970 and 2005, vehicle miles traveled of cars and light trucks in America increased by about 164% while vehicle-related emissions of carbon monoxide actually dropped by 67 percent and fine particulate matter by 62 percent. When coupled with similar declines from industrial and agricultural sources, it means that we are breathing healthier air today than at any time since the late 18th century.
However, the Oregon-California lawsuit was never about air pollution. The states were suing to reduce energy consumption in motor vehicles and used the regulation of carbon dioxide (which is not actually a pollutant) as a surrogate. But motor vehicles have consistently been getting more efficient for the past 35 years. In 1970, Btu consumed per vehicle-mile for cars averaged 9,250; by 2005, it had dropped to 5,401, a 42% improvement. Pick-up trucks and SUVs also showed a steady decrease in fuel: from 12,479 Btu per vehicle-mile in 1970 to 7,652 in 2005.
The lawsuit also ignored our success nationally in reducing one of the most potent greenhouse gases emitted by motor vehicles, oxides of nitrogen (NOx). One kilogram of NOx is roughly equivalent to 296 kilograms of CO2 over a 100-year time horizon, so it is a high-leverage pollutant. Between 1970 and 2006, auto-related emissions of nitrogen oxides declined by 48%. The governors seem to have overlooked this inconvenient truth.
Proponents of global warming regulation like to use 1990 as a baseline year for emissions, so how does Oregon stack up for the most powerful GHGs? Mobile-source NOx emissions in Oregon are 15.5 percent lower today than they were in 1990, while methane emissions have plummeted by 46% over that time period.
Total GHG emissions in Oregon, including CO2, peaked in 2000; we are now on a downward trend, which will continue indefinitely due to investments in better technology.
EPA appropriately rejected the state regulations because they would have imposed high costs on consumers (anywhere from $750-$1,500 per new car) with zero effect on global climate. The best thing the 17 governors can do now is gracefully accept their defeat, and then get out of the way so automakers and their investors can bring the next generation of technological improvements to the world.