Less pollution may boost global warming

E-mail this article Print this article

SANTA ANA, Calif. - A new study says some efforts to reduce air pollution could turn up the heat on another environmental problem: global warming.

The bizarre conclusion, in a paper to be published May 1 in the science journal Geophysical Research Letters, arose from a computer model of the atmosphere developed by atmospheric scientist Michael Prather of the University of California, Irvine.

By plugging known interactions among gases into the model, Prather and two scientists working in Japan found that two common pollutants, nitrogen oxides and carbon monoxide, help cause global warming - just as expected.

But the model also suggests that cutting nitrogen oxides without at the same time cutting carbon monoxide would eventually lead to a long-term increase of methane in the atmosphere.

Methane is one of the "greenhouse" gases thought to contribute to global warming.

A product of car exhaust, nitrogen oxides contribute to the formation of ground-level ozone, which can aggravate respiratory problems and even scar lungs.

Carbon monoxide, also produced by car engines, is also an important ingredient in forming smog.

The research does not mean that pollution-control efforts should be abandoned, Prather said, but that the balance of gases such as nitrogen oxides and carbon monoxide should be taken into account - otherwise, global warming could be inadvertently increased.

"You need to have an intelligent strategy, not to think that just by eliminating local pollution you can cure global warming," he said.