What is the Ozone Layer? Everyone does know about the Ozone (O₃) Layer which helps us by preventing Ultraviolet rays from The Sun to enter the Earth’s atmosphere and can cause very harmful effects on us. Or simply it is a dense stratosphere layer covering the Earth which contains massive quantities of ozone. The sheet or layer of (O₃) protects the entire Planet from all of the dangerous UV radiation coming from the sun.
The Ozone Layer Introduction
The ozone layer had been discovered by the French scientists Charles Fabry and Henri Buisson in 1913. The layer blocks 97 to 99 percent of the Sun’s medium-frequency ultraviolet radiation, which would otherwise theoretically harm near-surface exposed life forms. This Layer is also known as ozonosphere, it is in the upper atmosphere area, approximately 15 to 35 km of the layer. It contains a relatively high amount of ozone molecules (O₃). It is mainly present in Earth’s stratosphere. In the stratosphere air temperature increases with rising height, a phenomenon created by the ozone layer absorbing solar ultraviolet rays.
Much of the residual (O₃) resides in the troposphere, the cloud layer that stretches from the surface of the Earth up to the stratosphere. Near-surface ozone is mostly the result of encounters with certain contaminants, heavy sunshine, and hot weather conditions.
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How Ozone layer is formed
Ironically, this UV emission is actually what first creates the ozone. The formation of ozone is largely due to the dissolution of the chemical bonds within oxygen molecules (O2) by solar photons with high intensity. This method, called photodissociation, results in the formation of single atoms of oxygen which later bind intact molecules of oxygen to form ozone. Ozone is a special type of oxygen consisting of three atoms of oxygen, rather than the normal two atoms of oxygen. It normally occurs when the two atoms in an oxygen molecule (O2) are separated by some kind of radiation or electrical discharge, and may then independently recombine with other oxygen molecules to form ozone (O3).
Rising concentrations of atmospheric oxygen some two billion years ago forced ozone to build up in Earth’s atmosphere, a process that gradually led to stratosphere creation. Researchers agree that the creation of the ozone layer by filtering out toxic amounts of Ultraviolet radiation played a significant role in the production of life on Earth.
Importance of Ozone Layer
Ozone Layer came to public limelight when it was discovered that some chemical substances humanity creates, called chlorofluorocarbons, they make their way up into the stratosphere where they damage some of the (O₃) through a complicated sequence of chemical reactions. As a consequence of this finding, an international convention, called the Montreal Protocol, was signed in 1973 and the production of these chemicals was significantly reduced.
As a result of these efforts, the ozone layer has also begun to regenerate slightly, although some scientists suggest that the large volcanic eruptions that have occurred also we began observing the ozone layer with satellites in the late 1970s, may also have resulted in the depletion of the (O₃) layer.
Good and Bad Ozone
Good Ozone: It exists naturally in the upper atmosphere of the Earth where it forms a protective layer that protects us from the harmful ultraviolet rays of the sun.
Bad Ozone: Ozone is formed in the lower atmosphere of the Earth, close to ground level, when chemicals produced from vehicles, power plants, industrial boilers, refineries, chemical plants, and other sources chemically react in the presence of sunlight. Ozone is a toxic pollutant of the air at ground level.
The General Assembly of the United Nations has declared September 16 as the International Day for Ozone Layer Protection. Venus also maintains a thin ozone (O₃) layer on the atmosphere of the earth at a height of 100 kilometers.
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