Individually, use of our cars and lawnmowers and our refueling habits are not the main culprits in pollution. Cumulatively, however, these activities are responsible for much of the ozone-forming emissions in our region. Other sources of pollutants come from industry. However, industry is well-regulated and has greatly reduced its emissions. People, on the other hand, tend to live and pollute much more freely. Studies show that in St. Louis the activities of individuals regularly create between 30 to 50 percent of the pollutants that cause ground level ozone. It is not unheard of for exceedances of the ozone standard to take place on Saturdays - when most industrial emissions sources are shut down or operating at reduced rates. This demonstrates that the activities of individuals are part of the problem, and it is possible to be part of the solution.
High temperatures, usually in the 90's or above, are conducive to elevated ozone concentrations (Remember, ozone in the lower atmosphere, where we breathe, is a pollutant.). Also, the temperature inversions during warm summer months can trap the pollutants close to the ground, stopping the pollution from dispersing during the night. Thus, since we cannot control the weather factors that contribute to ozone formation, it is important to look at the human factors contributing to ozone formation in the lower atmosphere.