Ozone Depletion Essay

The Ozone layer is located in the Earth’s upper atmosphere. It acts as a barrier and absorbs majority of UV radiation before it hits Earth’s surface. Ozone is made up of three oxygen atoms that are naturally occurring molecules. The depletion of the ozone has become a worldwide issue and is caused by the release of CFCs into the atmosphere. CFCs release chlorine atoms which break down ozone molecules. The depletion of the ozone layer threatens to leave life on Earth unprotected from UV radiation. Chlorofluorocarbons (CFCs) contain chlorine, fluorine and carbon atoms. CFCs can be found in spray cans, in the plastics industry and in refrigerants. When UV rays in the upper atmosphere hit CFC molecules, a carbon-chlorine bond breaks leaving a single chlorine atom. This chlorine atom reacts with the ozone molecule causing it to breakdown. The breakdown of ozone leaves an ordinary oxygen molecule (O2) as well as a chlorine monoxide molecule. Because UV radiation breaks oxygen molecules into single oxygen atoms, the single oxygen atom then breaks up the chlorine monoxide. With the chlorine atom left by itself, it is then able to repeat the process of breaking down more ozone molecules. However, the depletion of the ozone is not only caused by CFCs. Halons, CH3CCI, CCI4, HCFCs, hydrobromofluorocarbons and methyl bromide are all linked with ozone depletion leaving life on earth vulnerable to the effects from exposure to UV radiation. With the depletion of the ozone, UV radiation becomes more accessible to life on Earth and effects from this radiation follow. Since ozone filters UV radiation, with ozone depletion comes higher levels of UV radiation hitting the surface of the Earth. The increase in ultra-violet rays consequently mean higher risk of skin cancers and cataracts in humans and animals. Higher levels of this radiation also damages materials such as plastics, harm certain crops as well as marine animals. Extra UV radiation deters the natural reproductive cycle of phytoplankton (a single celled organism at the bottom of the food chain) Scientists fear that the population of other species will decrease with the loss of phytoplankton. Since the depletion of the ozone layer, researchers have recognised obvious deviations in the reproductive rates of fish, shrimp and crabs as well as frogs and salamanders. These changes in organism’s reproductive rates and higher risks of skin cancer and cataracts can all be linked to the depletion of the ozone layer. Since CFCs have been released into the atmosphere, Earth’s naturally occurring ozone layer has been depleting. The ozone layer above the Antarctic has been majorly affected by CFC pollution since the mid 1980’s. However, CFCs were banned in 1987 to prevent further damage to the ozone layer. Results of ozone depletion can be dramatically seen throughout the southern spring and summer when the sun shines for longer periods at a time. Due to chlorine reacting with the Ultra-violet rays, ozone is destroyed on a scale of up to 65% during these months. Even though CFCs were banned in the 1980’s scientists estimate it will take another 50 years for chlorine levels to return to their natural levels. With CFCs being emitted into the atmosphere, the breakdown of ozone has resulted. Without the ozone filtering UV rays, higher levels of radiation are able to hit the Earth’s surface leading to higher rates in skin cancer and cataracts. Ozone depletion has also been linked with the obstruction of organisms natural reproductive cycles. Although they were banned in the late 1980’s, CFCs will continue to be present in the atmosphere for many more years causing ozone depletion to remain a worldwide issue.