Vehicle emissions, industrial operations, and topographical characteristics that trap pollution make Los Angeles one of the most polluted cities in the US.
Los Angeles, California
Bakersfield, in California's Central Valley, frequently has the worst air quality in the nation. Traffic, oil and gas production, and agriculture increase particulate matter and ozone.
Fresno shares Bakersfield's Central Valley location and air pollution issues. Topography and vast cultivation cause high particulate matter and ozone levels.
Phoenix has substantial summer air pollution due to hot heat, automobile emissions, and dust storms. Wildfires cause particulate matter surges in the city.
Phoenix has substantial summer air pollution due to hot heat, automobile emissions, and dust storms. Wildfires cause particulate matter surges in the city.
Pittsburgh, Pennsylvania
Houston's air pollution is severe due to refineries, chemical industries, and traffic congestion.
Cleveland's air pollution is caused by coal-fired power plants and industry. Air quality has improved, but the city still struggles with pollution.
Vehicle exhaust, industrial activity, and Louisville's terrain trap pollutants, causing high ozone levels.