What U.S. city is particularly noted for its problems with smog? Air Pollution Read more from Chapter Humanity and the Weather

Los Angeles has a rough time with smog. The brown haze that often lingers over the city is a result of several factors. Of course, the urban area is filled with cars and other sources of pollutants, but the natural environment conspires to make matters worse. First of all, very little rain falls in L.A., which might attract tourists and new residents but does nothing to wash away pollutants; and secondly, the city is in a basin surrounded by mountains. Ocean breezes blowing in from the west keep air pollution from escaping in that direction, but then the smog finds another barrier in the mountains that lie east, north, and south of the city. Even before Spanish and other European settlers came to the area, the Native American Chumash tribe called what is now Los Angeles the “valley of smoke,” because haze from brush fires and dust would be trapped there for long periods.