Ozone

Atmospheric ozone (O3) is found mostly between about 9 and 23 miles above the Earth's surface in a region called the stratosphere. This ozone layer acts as a barrier protecting life on Earth from harmful ultraviolet (UV) radiation from the sun. From 1970 on, scientists expressed concern that human-made chemicals, particularly chlorofluorocarbons (CFCs), were thinning the ozone layer. A 1976 report by the U.S. National Academy of Sciences (NAS) concluded that the ozone depletion hypothesis was supported by scientific observations. Calculations suggested a global ozone loss of 5 to 7 percent by 1995, with attendant increases in skin cancer, probable damage to human and animal DNA, as well as harmful effects on some crops.

As emergent social problems, the slowing of ozone depletion and the subsequently discovered ozone hole are remarkable success stories. Prior to the NAS report, environmentalists had put the ozone problem at the top of their list, and in 1978 the United States and several other countries moved to eliminate the use of CFCs in aerosol spray cans. The “styro wars” mounted by environmentalists led to successful public boycotts of McDonald's for using Styrofoam and rapid decreases in the use of aerosols.

While these initial successes diminished concern about the issue, 1985 brought the surprise discovery of an “ozone hole” over Antarctica. Where scientists had expected a steady and relatively slow depletion of ozone, this crater in the ozone column was so shocking that it took just 2 years to forge an international agreement. Indeed, the Montreal Protocol was signed before scientists established that the ozone hole was due to human-made chemicals rather than the unique conditions found in Antarctica.

The Montreal Protocol not only was the first international treaty on a global ecological problem but is [Page 645]widely regarded as a landmark regime and prototype for future negotiations. Its significant innovations include automatic provisions for review—these have led to a ratcheting up of the agreement—and funding by rich nations for adaptations by poorer nations. The United States took the lead in negotiating the protocol, and U.S. corporations began an energetic pursuit of substitute chemicals that, significantly, were not difficult to develop.

Sociologically, the stunning success of the solution to the ozone problem can be attributed to the availability of bridging metaphors to the popular culture and its practical intrusion into everyday life. The ozone hole can be encapsulated in a familiar “penetration” metaphor. The idea of lethal rays penetrating a damaged “shield” meshes nicely with resonant cultural motifs that include Star Wars and many video games. Practically, leakage through the shield is linked with melanoma, a deadly skin cancer, and the issue created a cultural whirlwind with President Ronald Reagan's skin cancers, political gaffes, warnings about the outdoors becoming dangerous, and the vulnerability of children, as well as the growth of a “safe sun” industry.

Observations and calculations suggest that ozone depletion has stabilized globally and long-term recovery is anticipated. Ozone depletion has become a lesser social problem, attracting mainly “news briefs,” while concern with safe sun has attenuated.