A new report lists the most polluted cities in the U.S. , including several California cities . David Pettit : http://blogs.discovermagazine.com/badastronomy/2011/02/10/the-most-polluted-cities-in-america/#.T7pj4tf1ZJY The intense truck traffic on L.A. 's freeways is a symptom of the L.A. area ports ' successes . He says Los Angeles , for example , needs to massively expand its public transit system . Pettit : California needs to accelerate development of clean , renewable energy .
A new report lists the most polluted cities in the U.S. , including several California cities . David Pettit : http://blogs.discovermagazine.com/badastronomy/2011/02/10/the-most-polluted-cities-in-america/#.T7pj4tf1ZJY He says Los Angeles , for example , needs to massively expand its public transit system . Pettit : California needs to accelerate development of clean , renewable energy .