California’s Draconian Auto-Emission Standards Won’t Reduce Global Warming

Published October 1, 2004

California’s state legislature is currently considering a proposal to limit carbon dioxide emissions from cars and trucks in hopes of staving off global warming. Gov. Arnold Schwarzenegger (R) has expressed support for the law and promised to fight any challenges by automakers or the federal government.

The proposal stems from a law, AB 1493, signed by former California Gov. Gray Davis in 2002, that requires the California Air Resources Board (CARB) to set emission standards this year for carbon dioxide and other greenhouse gases. In particular, CARB is required to produce regulations limiting greenhouse gas emissions from automobiles.

CARB recently issued its draft regulations and will present its final proposal to the state legislature on January 1, 2005. Schwarzenegger repeatedly stated in his campaign for governor that he supports AB 1493.

Under CARB’s proposed regulations, California consumers would pay several hundred dollars more for every vehicle they buy, as a result of the state’s effort to cut tailpipe emissions from most new vehicles by nearly 30 percent over the next decade.

California is the only state that can set its own vehicle pollution standards, because it began regulating air pollution before the federal government did. Other states can adopt either the federal vehicle pollution standards or those established by California.

Based on Questionable Assumptions

Wishful thinking aside, reducing carbon dioxide emissions from California cars and trucks cannot have any effect on the global climate, owing to a few simple facts of physics.

Transportation accounts for about one-third of all carbon dioxide emissions in California. The new cars and trucks covered under the proposed regulation account for only a few percent of total transportation emissions each year, and the proposed law would reduce those emissions by about 30 percent. As a result, the law would reduce California’s carbon dioxide emissions by about 1 percent.

As a whole, the United States accounts for about one-quarter of global human greenhouse gas emissions each year, a share that is falling fast as developing countries industrialize. California is responsible for around 5 percent of that, so even with its highly industrialized economy and large and affluent population, the state accounts for only about 1 percent of global greenhouse gas emissions.

Carbon dioxide makes up only 4 percent of the Earth’s greenhouse gas component. In the past 60 years, mankind has increased carbon dioxide concentrations in the atmosphere by about 30 percent, mostly by burning fossil fuels. A 30 percent increase in a gas that constitutes only 4 percent of the greenhouse effect means the human presence on Earth may have increased the total greenhouse effect by just over 1 percent.

Laboratory physics tells us that a doubling of the concentration of carbon dioxide in the atmosphere, which scientists say may occur by the end of this century, would increase the amount of trapped heat by about four watts per square meter of surface area. (These are the same watts you use to measure the energy of your light bulbs, so picture a very dim four-watt bulb.) The sun continuously contributes immensely more heat than this–some 342 watts per square meter–to the outer layer of the Earth’s atmosphere. Thus, we humans may increase the total heat available at the Earth’s surface by no more than 1 percent.

Greenhouse Reduction Would Be Minute

So … simple facts and the laws of thermodynamic physics tell us the proposed California law would likely reduce the human impact on world climate in the order of 1 percent of 1 percent of 1 percent of 1 percent. That means the proposed law would solve about one millionth of 1 percent of the global warming problem.

Even this overstates the possible effects, however, since improving fuel economy to reduce car and truck emissions is likely to encourage people to drive more, leading to more congestion and more emissions, and other changes in behavior in California and in other states that would cancel out some or all of the possible emission reductions.

The number of absurd assumptions required to believe this new regulation would actually protect the environment exceeds the odds against winning a record-breaking Powerball lottery. California, however, is the state that requires bags of sand for backyard sandboxes to bear labels saying “this product is known by the State of California to cause cancer” and pays bounties to lawyers who sue home businesses that make such environmentally suspect products as scented candles.

Schwarzenegger really should know better. Having defeated so many villains in the movies, he ought to recognize that global warming is an almost entirely natural and unthreatening process that cannot even be fought, much less beaten.


Dr. Jay Lehr ([email protected]) is science director of the Heartland Institute and editor of Wiley’s Remediation Technologies Handbook and other major science reference books.