The conventional theory was that ozone loss was related to the use of chlorofluorocarbon compounds (also called freons): Methyl chloroform, carbon tetrachloride and trichloroethane-commonly used in dozens of applications including refrigerants, aerosol propellants and solvents. Their industrial use is based upon their stability, which is why they can float undamaged into the atmosphere. This stability ensures that they can en-dure the path up to the stratosphere. Once there, these stable molecules are theoretically broken apart by unfiltered ultraviolet radiation into chlorine and bromine ions. These two ions in turn break apart the three-oxygen ozone combination. As a result, oxygen O2 molecules tend to convert less to the ozone configuration O3 in the absence of the sun’s rays. The remaining oxygenated no-ozone areas theoretically vortex into holes, leaving the classic ozone hole. While chlorine and bromine have been observed as catalytic ozone destroyers for many years, conclusive proof that the ozone layer was disintegrated only came in 1984, and the theory emerged in the years following.
However, this chemical response to humankind’s planetary mismanagement is only part of the picture. Peering back to each year’s satellite measurements of the ozone, even in the late eighties and nineties when the hole doubled in size, there have been a variance of ups and downs. In 1987, the hole was measured at 22.45 square kilometers. In 1988, it dropped down to 13.76. In 1989 and 1990, it popped back up to 21.73 and 21.05 respectively. In 1992, it grew to 24.90. In 1993, it sagged a bit to 24.017; and in 1994, it sagged again at 23.429. Was the issue resolving during this era? Hardly. In 1996, it jumped again to 26.96. In 1997, it sagged again to 25.13 but in 1998 it jumped again-this time to 28.21. It fell another couple of square kilometers in 1999 and jumped again in 2000. In the years following 2000, it jumped from 26 to 21, to 29, to 23, and to 27, respectfully. Then it jumped to a record 30 again in 2006, and then fell again in 2007 back to 24.
It appears there is more involved than simply chlorofluorocarbon compounds. There are rhythmic variations in temperature, pressure, and most likely magnetic fields. This later point relates to the fact that the hole seems to be positioning toward the annual ozone hole that forms in the troposphere around the South Pole on a seasonal basis. Researchers now believe that the catastrophic ozone depletion in the lower stratosphere may relate quite closely with the increase in carbon emissions as well, which tends to cool the stratosphere and provide a blanketing effect. This in turn shields heat from rising-resulting in the well-known greenhouse effect.
The mild decrease after 2000 was thought to be due to the reduction of CFCs-as mandated by law in many countries. The World Meteorological Organization states that should our CFC use continue to fall, it may take another 50 years or so to bring the ozone levels in the stratosphere back to normal. That is, if the global warming trend effect does not outpace the CFC decrease’s effects, which appears to be a possibility.
The bottom line is that it appears we have effectively punctured a hole in the planet’s breathing apparatus not simply with CFCs, but with carbon emissions. Just as a puncture or wound causes an inflammatory and repair process, causing a scabbing and detoxification process, the wound of the ozone hole appears to be undergoing a healing process, which is alternatively subjected to further wounding as we continue to dump pollutants into the atmosphere.