• What is the ozone layer?
• Composition of the ozone layer
• Importance and functions of the ozone layer
• The hole in the ozone layer: causes and consequences
• How to take care of the ozone layer?

We explain what the ozone layer is and its importance for life. Also, causes and consequences of ozone layer holes.

The ozone layer is being weakened by man-made gases.

What is the ozone layer?

The ozone layer is a protective layer within theearth's atmosphere which has the function of preserving the life of planet Earth acting as a shield against ultraviolet radiation (UV rays).

It is located between 15 and 50 kilometers high from the Earth's surface and absorbs more than 97% of the solar radiation that is harmful to the living beings.

Composition of the ozone layer

The ozone layer is made up of ozone, a gas made up of a molecule It has 3 oxygen atoms (instead of 2, as in the oxygen molecule). This third atom returns to poisonous oxygen, since ozone is deadly when inhaled.

The ozone molecule is formed in thestratosphere by the action of solar radiation in a process called photolysis. This process occurs when the rays of the Sun break down an oxygen molecule present in the stratosphere and divide it into two atoms. When one of these oxygen atoms joins with an O2 molecule, ozone is produced, which is distributed and forms a thin layer that surrounds the planet Earth.

The ozone concentration in the atmosphere is not constant and varies according to altitude and weather conditions.

Importance and functions of the ozone layer

Charles Fabry was one of the discoverers of the ozone layer.

The ozone layer was discovered in 1913 by French physicists Charles Fabry and Henri Buisson. Years later, British meteorologist Gordon Miller Dobson examined his properties and he developed the spectrophotometer, an instrument that allows ozone to be measured from the Earth's surface.

This layer is essential to preserve life as it is known, as it filters a large proportion of the solar rays that are harmful to living beings, and lets through the rays necessary for life. Ultraviolet rays that are not filtered by ozone generate burns and visual problems in the human being, and until death of some single-celled organisms.

The destruction of the ozone layer occurs naturally, when the level of ozone present in the atmosphere is altered; and by the action of man who, through products and processes, releases harmful gases into the atmosphere.

The hole in the ozone layer: causes and consequences

The low density of ozone present in the layer (which can occur due to natural causes or human action) results in the creation of holes (which are usually found at the poles). These holes are sectors of the ozone layer with little ozone gas presence through which UV rays filter more easily.

In recent decades, the destruction of the ozone layer has been accelerated by human use of halocarbons. These substances (present in pesticides or aerosols) emit gases into the atmosphere that cause the thinning of the ozone layer.

The main risk of holes in the ozone layer is that they increase the exposure of planet Earth and living beings to UV radiation, which is harmful to health. These rays age and damage the skin's DNA, leading to burns and skin cancer.

Faced with this problem, theUN (United Nations) signed the Montreal Protocol in 1987 and in 1994 the United Nations General Assembly declared September 16 as the International Day for the Preservation of the Ozone Layer.

How to take care of the ozone layer?

There are certain gases that contribute to the weakening of the ozone layer. It is important to know them and become aware of the risks involved in the excessive use of products that they emit gases harmful. Thus, to take care of the ozone layer, it is necessary to avoid using products that contain harmful gases. Among the most prominent are:

• CFC (Chlorofluorocarbons). Compounds containing chlorine, fluorine and carbon that are used in aerosols, solvents, air conditioners and as an insulating material. They reach the stratosphere, dissolve, and chlorine breaks down the ozone layer.
• HCFC (Hydrochlorofluorocarbons). Compounds containing hydrogen, chlorine, fluorine and carbon that are used as replacements for CFCs. In this case, chlorine also damages the ozone layer, but hydrogen makes them less stable.