So many people talk about the thinning of the ozone layer, but what does that really mean? In this new series, “Global Climate Change Wednesdays,” I will explain some basic environmental concepts that seem to confuse and mystify people.

       To begin, CFC’s (Chlorofluorocarbons) are synthetic compounds that contain chlorine, fluorine, and bromine. These compounds are commonly found in industrial solvents, refrigerator coolants, hairsprays, and other consumer spray items. Although these compounds are not particularly dangerous to human health, they are detrimental to the environment. However, one aspect needs to be straightened out: the thinning of the ozone layer and global warming are two separate entities. Ozone depletion does not result in significantly higher temperatures.

       First, when CFC’s are released into the atmosphere, ultraviolet rays in the atmosphere break off chlorine atoms. These trace atoms travel through the troposphere (the lowest layer of the atmosphere where weather occurs) and migrate to the stratosphere (where the ozone layer is). This layer blocks most of the harmful UV rays that cause cancer and sunburns in humans and other organisms (i.e. amphibians). Ozone (which is a criteria pollutant in the troposphere and is an element of photochemical smog) has a chemical formula of O3 (three oxygen atoms bound together). The chlorine atoms that were released from CFC’s attack the ozone (especially in the Polar Regions) and split it into oxygen (O2) and chlorine monoxide (ClO). This process is a positive feedback loop, meaning chlorine atoms from chlorine monoxide and other chlorine-containing compounds break free and attack new ozone molecules over and over again. This splitting of ozone compounds continually “thins” this layer which protects all life on Earth.
       What are some of the effects of the thinning ozone layers? It results in increased sunburns, skin cancer, and a decrease in amphibians. Also, primary productivity (the energy produced by autotrophs) decreases because the UV rays damage cells. Although this was short, this is the crash course in Chlorofluorocarbons. They were banned in the Montreal Protocol of 1987; this agreement has had more success than the Kyoto Protocol (which tried to reduce greenhouse gas emissions).