Environmental Science Basics, Air
In this exercise we will be examining ground-level ozone, commonly referred to as "smog" ("smoke" + "fog" = "smog"). Smog is formed by the combination of air pollutants and sunlight, and can have adverse effects on humans and other organisms. You have likely heard of ozone in a different capacity. Ozone also occurs high above the earth's surface in the stratosphere, where it serves a protective function by blocking harmful ultraviolet radiation from the sun. The ozone in each case is the same molecule (three bound oxygen atoms), but in one location (high in the atmosphere) it is beneficial to living things, and at another location (ground-level) is harmful. Realizing these "two faces" of ozone is important before proceeding, so look over the brochure below from the U.S. Environmental Protection Agency.