TCS Daily

Clearing the Air about Cars and Trucks

By Robert C. Balling - March 21, 2005 12:00 AM

The environmental activist group Union of Concerned Scientists has launched an attack on the auto industry blaming it for contributing to smog and "global warming pollution". As is so often the case, these concerned scientists seem to have no concern for science. Let's look at some facts.

Smog is a mixture of pollutants, principally ground-level ozone, produced by complex chemical reactions in the air enhanced by sunshine, high temperatures, and calm winds. The Union of Concerned Scientists is correct in noting that a major portion of smog-forming chemicals comes from burning gasoline in our fleet of vehicles. However, in the case of smog, the newest vehicles are far cleaner than the cars and trucks from decades ago. And as time goes on, these older vehicles will be eliminated, and the principal smog producers will vanish from the landscape. I have been involved in studying air quality in Phoenix, and contrary to popular perception, the hard data show that visibility and air quality have improved over time in the city, despite a very large increase in population.

The Union of Concerned Scientists refers to something they call "heat-trapping carbon dioxide pollution". They are correct that burning fossil fuels in vehicles produces carbon dioxide and indeed, carbon dioxide traps heat and contributes to the greenhouse effect and global warming. However, carbon dioxide is not a pollutant and even the United States Environmental Protection Agency does not list carbon dioxide as a pollutant. Carbon dioxide is naturally-occurring and responsible for life on the planet. In fact, carbon dioxide concentrations were much higher in the past, millions of years ago, when plants evolved around the world. Literally thousands of biological experiments show that when carbon dioxide levels increase, plants grow faster, bigger, more resistant to any number of stresses, and far more efficient in their use of water.

The Union of Concerned Scientists suggests that carbon dioxide emitted from American vehicles is contributing to global warming, and in fact, they are correct. However, if you have exhaled while reading this sentence, you have emitted carbon dioxide and to some degree, you have contributed to global warming. Across the globe, human activities result in an emission to the atmosphere of approximately 6.5 billion tons of carbon (not carbon dioxide). Of that amount, 23 percent comes from the United States, and of that amount, approximately one-fifth comes from our vehicular fleet. The American fleet constitutes less than five percent of emissions globally: While the global emission of carbon is 6.5 billion tons, the emission from the American fleet is approximately 0.3 billion tons. Even if the fleet vanished from the face of the earth, human activities would still result in 6.2 billion tons of carbon, and the atmospheric concentration would continue to rise. Like it or not, with or without cars and trucks in the United States, the concentration of carbon dioxide will double this century, and the year when this will occur is not impacted much by American cars and trucks.

Another point to consider is that many developing countries have no obligation via the Kyoto Protocol to reduce or even stabilize emissions of carbon dioxide. China, India, Pakistan, Brazil, Russia, and many other countries are planning substantial increases in electrical generation, and almost all of that electricity will be generating by consuming coal, oil, and natural gas. What happens to the cars in America is dwarfed by orders of magnitude by development in the rest of the world. As the rest of the world increases their emissions of carbon dioxide, the American fleet becomes more and more trivial in terms of global emissions.

The Union of Concerned Scientists must do a more credible job presenting the science behind smog, the greenhouse effect, and enhanced global warming. Like many other groups, they seem to be on an environmental crusade in which facts are distorted to encourage their desired behavior. The auto industry is very much at the mercy of the buying public - they can manufacture small electric cars all day, but in a marketplace where people demand safety over fuel efficiency, we will continue to see larger cars in the fleet. However, those larger vehicles are remarkably clean in terms of smog contribution, despite the claims of the UCS. The cars undoubtedly produce carbon dioxide, but their total emission is small in terms of global carbon dioxide emissions.

Scientists throughout the world concede that even if the Kyoto Protocol magically stabilized global emissions to 1990 levels, we would never be able to detect its climate impact. Similarly, the American fleet could totally vanish, and its climate impact would never be detectable.

These facts fly in the face of the latest distorted message coming from the Union of Concerned Scientists.


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