A Report on Ozone and CFCs, Essay Example

Over the last twenty years, a great deal of information has been presented by various scientists and researchers concerning global warming and climate change, but little has been done on another pressing environmental problem, being the depletion of ozone in the earth’s atmosphere. According to the Environmental Protection Agency (EPA), ozone is a “bluish gas that is harmful to breathe” with almost 90% of the earth’s ozone confined to the stratosphere, referred by atmospheric scientists as the ozone layer. The main purpose for the ozone layer is protection from ultraviolet radiation (UVB) emitted by the sun which is deadly to living organisms (The Process of Ozone Depletion, 2010).

As a result of anthropogenic influences (i.e., related to human activity), the amount of ozone in the earth’s stratosphere has been depleted because of the presence of CFCs or chlorofluorocarbons, a chemical compound composed of chlorine, fluorine, and carbon. The process of depletion begins when CFCs which are commonly used as refrigerants for air conditioners and solvents in manufacturing plants, enter the atmosphere and are mixed in with the air via wind currents in the troposphere. After several years, the CFC gases end up in the stratosphere where they virtually dissolve ozone. Some of the most common CFCs (some being banned as of 2015) includes CFC-11, CFC-12, CFC-113, CFC-114, and CFC-115 with the first two being the most destructive. These CFC gases also contribute to global warming by allowing more UV light to reach the earth’s surface (The Process of Ozone Depletion, 2010).

Today in 2015, most of the information and data available on the depletion of the ozone layer is provided through images and measurements made by earth-orbiting spacecraft controlled by the Goddard Space Flight Center and the National Aeronautics and Space Administration. These highly advanced instruments measure the amount of ozone in the stratosphere mostly over the continent of Antarctica, due to ozone being concentrated in this portion of the atmosphere (The Process of Ozone Depletion, 2010).

From a scientific standpoint, UV light breaks down the chemical compounds found in CFCs. When this occurs, other chemicals like hydroflurocarbons, carbon tetrachloride (which is highly flammable in a liquid and gaseous state), release chlorine atoms. Other atoms are released by methyl bromide and halons which are composed of bromine, fluorine, and carbon, and is normally found in fire extinguishers (the basic chemical equation for this process is  CFC₃ = CL=O₃ =O ₂ ). It is these gases (especially the halons) that are responsible for the destruction of ozone in the earth’s atmosphere. It has been estimated that one chlorine atom can destroy over 100,000 ozone molecules before it is removed from the stratosphere (The Process of Ozone Depletion, 2010).

Fortunately, there are now a number of alternatives to CFCs. According to research scientist Charles Welsh, CFCs have been replaced with hydrochlorofluorocarbons (HCFCs) which are “less stable in the lower atmosphere and break down before reaching the ozone layer.” However, research has shown that some HCFCs also contribute to chlorine buildup. This discovery then led to other alternatives like hydrofluorocarbons (HFCs) “which exhibit even shorter lifetimes in the lower atmosphere” (2013).

One of these compounds, known as HFC-134a, is currently being used as a replacement for CFCs in automobile air conditioners. Other refrigerants like a propane/isobutane mixture are also used in mobile air conditioning systems in numerous nations, especially the United States which has banned a number of CFCs. Overall, research has shown that these replacements for CFCs “have negligible environmental impacts” which explains their worldwide use today in 2015 (Welsh, 2013).

The most recent information and data on ozone depletion can be found in the journal Nature Geoscience which has published scientific articles on subjects like ozone depletion and biology, skin cancer and the depletion of the ozone layer, and the growth of the so-called “ozone hole” which has affected the climates of Antarctica and South America. Thus, the scientific evidence clearly indicates that the depletion of ozone in our earth’s atmosphere affects every human being on the planet which mandates that more must be done to halt the use of all CFCs on a global scale.

References

The process of ozone depletion. (2010). EPA. Retrieved from http://www.epa.gov/ozone/science/process.html

Welsh, C. (2013). The ozone hole. Retrieved from http://www.theozonehole.com/cfc.htm