Effect MTBE Large cities have long been dusty, sooty, often dirty places to live. In 1881, Chicago and Cincinnati passed ordinances to reduce soot and smoke from trains and furnaces. Urban areas are particularly susceptible to the accumulation of air pollutants because of the large quantity and diversity of emissions in a concentrated area. These emissions can cause health problems and reduce visibility.
Air quality is in large part a function of the weather and atmospheric conditions.
The concentration of pollutants in the air can vary greatly on days when emissions rates remain unchanged. Wind disperses pollutants and prevents a buildup in a local area. When the air is stagnant, a concentration of pollutants can result. Geography also affects air quality. Higher altitudes generally have greater wind speeds because there are fewer barriers to block or slow down wind.