The ozone layer is found in the stratosphere and is approximately 15 to 30 km high. It is made up of ozone gas (O3) that is made up of three oxygen atoms. They are released into the atmosphere and then one of them gets together with an oxygen molecule, forming an ozone molecule. The latter splits after absorbing ultraviolet rays (UV) and forms a new oxygen molecule. The process begins again in this new molecule. This is produced because O3 is in a continuous process of formation and destruction.
Ozone accumulates in the atmosphere, and as it does so in great amounts, it becomes a real shield that protects against ultraviolet radiation coming from the sun, making life on Earth possible.
Destruction of the ozone layer
During the last time, it has been talked about an important decreasing of the ozone layer, which has the form of a real hole, as big as the United States and as deep as Mount Everest hight. In fact, it is believed that, in some areas, the amount of stratospheric ozone has diminished in a 60%.
This weakening is directly related to the use of a chemical component produced by the Man, the chlorofluorocarbon (CFC) present in diverse products, such as sprays, air conditioning equipments and cooling systems. These products, with the action of light, emit an active chlorine that react on the ozone and decompose it. Other components that affect the ozone layer because they contain chlorine (CI) are: methyl chloroform (a solvent), carbon tetrachloride (an industrial chemical) and substances that contain bromine (Br), such as halons, used to put fire out.
The diminishing of the layer is more notorious in the poles, mainly in the South Pole, although during the last time, the North Pole has also been affected.
In the south area, where the quantity of ozone is less, ultraviolet radiations get to the Earth’s surface, causing damage in the flora and fauna.It is worth to point to out that this weakening is a seasonal phenomenon that appears as of spring, because in this season the radiation is higher.
Any excessive level of radiation UV (especially A and B) that get to the Earth’s surface can damage the people’s health, because it affects in the tendency to get skin cancer, eye lesions and deterioration of the immunology system.
According to the latest data, a constant diminishing of a 10% in the ozone layer can increase a 26% of the probabilities of getting skin cancer. People with very white complexion are more susceptible of getting this type of cancer. Eye lesions are the most common with an excessive level of UV radiation, such as cataracts, crystalline lenses deformation and presbyopia (sight defect consisting on the diminishing of the capability of seeing in short distances). Cataract is a disease that causes blindness to a million of people in the world, and a reduction of a 1% in the ozone can cause a 10% more of cases.
Also, continued exposure to UV rays can damage the functioning of the body’s immunological system. Some recent studies have confirmed that ultraviolet rays affect the body’s defenses, increasing cases of infectious disease.