Question - What are the two types of smog and how do they differ?
Answer - The cited article notes “……..smog can be separated into two types: industrial smog and photochemical smog. Industrial smog occurs in foggy cool weather, typical of that in London. Photochemical smog develops in hot dry climates such as Los Angeles and Mexico City. Although ozone is the primary pollutant for photochemical smog, industrial smog (including Chinese haze) contains particulate matter, sulfur dioxide, nitrogen dioxide, and carbon monoxide, and sometimes ozone.” (Cai H and Wang C. Surviving with smog and smoke. Precision interventions? 2017 Chest 152(5):925-929)