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Correcting the record on ozone

Ezra Wood
Friday December 21, 2001


“The driving force behind energy consumption” (Berkeley Daily Planet, 12/18), by Alice La Pierre, contains a common error in confusing “good” stratospheric ozone with ground-level “bad” ozone. Ms. La Pierre states that the resultant air pollution from increased vehicle emissions “…will contribute to the destruction of the ozone…” The exact opposite is true, actually: the nitrogen oxides and hydrocarbons emitted by vehicles contribute to the production of ground-level ozone, which is an irritating pollutant and the main component of smog.  

Depletion of ozone in the stratosphere (the layer of the atmosphere that extends from 10-50 km above the surface of the planet) is a separate environmental problem, caused primarily by chlorofluorocarbons (CFC’s). Stratospheric ozone is known as “good” ozone because it shields the planet from harmful ultraviolet light. “Ozone destruction” refers to the overall thinning of the ozone layer and the dramatic formation of the ozone hole over Antarctica every spring. 

Ezra Wood 

Department of Chemistry 

UC Berkeley