Study reveals critical factors affecting urban...( COLUMBUS Ohio...)

COLUMBUS, Ohio - The most critical factor affecting ozone concentrations in U.S. cities is beyond the control of local regulators: It is the amount of ozone that drifts into a city from outside its boundaries, a new nationwide study confirms.

The study also found that the number and placement of road intersections within a city is the largest factor that determines carbon monoxide levels.

Researchers at Ohio State University used a comprehensive statistical analysis to determine what factors most influenced levels of ozone and carbon monoxide - both major pollutants -- in more than 100 U.S. cities. This analysis is the first of its kind to use real-life data to look at how a variety of factors - from car emissions to weather to population - affected air quality in the nation's cities.

The findings also indicated the positive impact that public transportation, forests and farmland in cities can have in lowering levels of ozone and carbon monoxide.

"Researchers already know most of the causes of air pollution in our cities, but the advantage of our statistical analysis is that we can measure the relative importance of each of these causes," said Jean-Michel Guldmann, co-author of the study and professor of city and regional planning at Ohio State.

The study
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Contact: Jean-Michel Guldmann
Guldmann.1@osu.edu
614-292-2257
Ohio State University
26-Jun-2001