By James Gerken, The Huffington Post
On the eve of "Carmageddon II," researchers from the University of California, Los Angeles revealed that last year’s July 15-17 closure of Interstate 405 resulted in significant air quality improvements in the vicinity of the freeway.
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The researchers also found that with an overall decrease in traffic across the Los Angeles area during the Carmageddon weekend, "air quality … 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."
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Yet the air quality improvements disappeared with the return of heavier traffic the next week….
https://www.huffingtonpost.com/2012/09/29/carmageddon-los-angeles-air-quality_n_1925523.html?utm_hp_ref=green
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