Ozone depletion is a process of gradual thinning of earth’s ozone layer. This is a region which is located at earth’s upper atmosphere and absorbs most of the Sun’s ultraviolet radiations. High concentration of ozone is contained by the ozone layer related to other parts of the atmosphere. However, it’s still small in relation to other gases in the stratosphere. There are nearly ten parts per million of ozone in the ozone layer while the average ozone concentration in the atmosphere of the globe as a whole is about 0.3 parts per million.
Ozone Depletion Potential
The ozone depletion potential of a substance is a measurement of how much it can damage the ozone layer relative to trichlorofluoromethane (CFC-11). It has an ODP of 1. Substances with higher ODP’s are more dangerous for the ozone layer. Some common ozone-depleting substances and their ODPs include:
- Chlorofluorocarbons (CFCs): ODPs range from 0.01 to 1.0
- Halons: ODPs range from 1.0 to 10.0
- Methyl bromide: ODP of 0.6
- Carbon tetrachloride: ODP of 1.1
Ozone depletion and climate change
Climate change and the ozone depletion are two interconnected environmental issues of the modern world. The substances of ozone depletion are also known as greenhouse gases, which means that they trap heat in the atmosphere. The whole process can contribute highly to global warming and climate change. Apart from this, the climate change can also affect the ozone layer. For instance, warmer temperatures of the Earth can lead to stronger winds in the stratosphere. The ozone depleting substances from the lower atmosphere up to the ozone layer can be mixed because of this process. This is why both these two issues are interconnected and both of them are highly dangerous for the whole world.
Ozone Depletion’s Effects on the Environment
Ozone depletion causes several types of negative effects on the environment. That includes increased risk of skin cancer and cataracts, damage to plants and animals, and weakened immune system of the human. Initially, ozone layer absorbs ultraviolet radiation from the sun. However, if the ozone layer is thinned, more ultraviolet radiation can be able to reach the surface of the Earth. That can increase the risk of skin cancer and cataracts. On the other hand, this ultraviolet radiation can also cause huge damage to plants and animals, including phytoplankton, which are microscopic organisms that form the base of the marine food chain in the sea. Finally, aggravated tradition can also surprise the immune system of the human being. It can result in making the people more susceptible to infections.
Ozen Depletion Gases
The main ozone-depleting gases are:
- Chlorofluorocarbons (CFCs): CFCs were once widely used in refrigerators, air conditioners, and fire extinguishers.
- Halons: Halons were also used in fire extinguishers.
- Methyl bromide: Methyl bromide is a pesticide that is used to control pests in agriculture and horticulture.
- Carbon tetrachloride: Carbon tetrachloride is a solvent that was once widely used in dry cleaning and metal degreasing.
Ozone Depletion Reaction
Ozone depletion is caused by a chemical reaction between ozone and ozone-depleting substances. When an ozone-depleting substance breaks down, it releases chlorine or bromine atoms. These atoms can then destroy ozone molecules. The ozone depletion reaction can be summarized by the following equation:
O3 + Cl/Br → O2 + ClO/BrO
This reaction can be repeated over and over again, with each chlorine or bromine atom destroying many ozone molecules.
International Efforts to Protect the Ozone Layer
The Montreal Protocol on Substances That Deplete the Ozone Layer was signed by the international community in 1987. This is known as a landmark agreement in protecting the ozone layer of the Earth that has phased out the production and consumption of most ozone depleting substances. As a result of the Montreal Protocol, the ozone layer is slowly recovering. However, it is still important to protect the ozone layer and to continue to reduce our emissions of ozone-depleting substances.
We can perform several types of activities for helping protect the ozone layer from depleting. We can avoid using products that contain ozone depleting substances, which will be very much beneficial for the ozone layer. Besides, air conditioner and refrigerators are known as some major threats to the ozone layer. We can have our air conditioner and refrigerator serviced regularly to ensure that they are not leaking any ozone-depleting substances. Besides, we should also support policies that protect the ozone layer from depleting.