Ozone holes are areas in an ozone layer of Earth where the content of gas of the ozone protecting the planet from radiation is not enough. Usually process of their education is connected with human activity, but there is an opinion that the origin of ozone holes is absolutely natural.
Ozone hole
Ozone – gas which is produced from oxygen under the influence of ultraviolet rays. The atmosphere of Earth has an ozone layer at the height about 25 kilometers: the layer of this gas densely surrounds our planet, protecting it from high concentration of ultraviolet. If not this gas, intensive radiation all could kill live on Earth.
Ozone layer quite thin, it cannot protect the planet from penetration of radiation which perniciously affects a condition of ecosystems and causes diseases in people completely. But its long time was enough to protect Earth from danger.
In the eighties the 20th century it was revealed that in an ozone layer there are sites where the content of this gas is strongly reduced – so-called ozone holes. The first hole was found over Antarctica the British scientists, they were struck with phenomenon scales – the site with a diameter more than one thousand kilometers had almost no protective layer and was exposed to stronger ultra-violet radiation.
Later also other ozone holes smaller by the size, but not less dangerous were found.
Reasons of formation of ozone holes
The mechanism of formation of an ozone layer in the atmosphere of Earth is quite difficult, and can lead various reasons to its violation. At first scientists offered a set of versions: and influence of the particles formed at atomic explosions and impact of a volcanic eruption El-Chicon, were expressed even opinions on activity of aliens. The lack of sunlight, formation of stratospheric clouds, polar whirlwinds can be the causes of exhaustion of an ozone layer, but most often concentration of this gas falls because of its reactions with various substances which can have both natural, and anthropogenic character. Molecules of ozone collapse under the influence of hydrogen, oxygen, bromine, chlorine, chlorohydrogen, organic compounds. So far scientists cannot unambiguously tell whether formation of ozone holes mostly is caused by human activity, or it has natural origin.
It was proved that the freona which are allocated during the operation of many devices cause losses of ozone in middle and high latitudes, but they do not influence formation of polar ozone holes.
It is probable that the set of many, both human, and natural factors, led to formation of ozone holes. On the one hand, the volcanic activity, with another increased, people began to influence too seriously the nature – the ozone layer can suffer not only from release of freon, but also from collision with the failed satellites. Thanks to reduction of quantity of the throwing-up volcanoes since the end of the 20th century and to restriction of application of freon the situation began to improve a little: recently scientists recorded small restoration of a hole over Antarctica. More detailed study of destruction of ozone will allow to prevent emergence of these areas.