Paulson on air quality during 2011 Carmageddon
In study findings announced Sept. 28, UCLA researchers report that they measured air pollutants during last year's Carmageddon (July 15–17) and found that when 10 miles of the 405 closed, air quality near the shuttered portion improved within minutes, reaching levels 83 percent better than on comparable weekends.
Because traffic dipped all over Southern California that weekend, air quality also improved 75 percent in parts of West Los Angeles and Santa Monica and an average of 25 percent regionally—from Ventura to Yucaipa, and Long Beach to Santa Clarita.
The study was led by two professors at UCLA's Institute of the Environment and Sustainability: Yifang Zhu, who is also an associate professor of environmental health sciences at the UCLA Fielding School of Public Health, and Suzanne Paulson, who is also a professor of atmospheric and oceanic sciences.
While the researchers expected cleaner air, they didn't expect the improvement to be so dramatic.