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  World Day for the Preservation of the Ozone Layer

Nuclear Fusion Power Plants

fog as Ozone Layer

California, United States the fog on the bridge seems to depict pollution and the ozone hole

International Day for the Preservation of the Ozone Layer (informally and simply called Ozone Day) is celebrated on September 16 designed by the United Nations General Assembly. This designation had been made on December 19, 2000, in commemoration of the date, in 1987, on which nations signed the Montreal Protocol on Substances that Deplete the Ozone Layer. In 1994, the UN General Assembly proclaimed 16 September the International Day for the Preservation of the Ozone Layer, commemorating the date of the signing, in 1987, of the Montreal Protocol on Substances that Deplete the Ozone Layer. The closure of the hole in the ozone layer was observed 30 years after the protocol was signed. Due to the nature of the gases responsible for ozone depletion their chemical effects are expected to continue for between 50 and 100 years

A true protector of the planet

Ozone is an allotropic form of oxygen, i.e. an element formed by the same molecules (in this case three oxygen molecules) but with different chemical bond structures. This ozone is very present in the lower part of the stratosphere, the second of the five layers which conventionally divides the Earth's atmosphere, and is identified as a greenhouse gas. This is absolutely not a bad thing - the greenhouse effect in itself is not only natural, but indeed it is fundamental for life on the planet - as its particular properties allow it to retain a good part of solar radiation. The rays of the sun that we like so much in the summer for sunbathing, in fact, are "filtered" by the ozone which absorbs a lot of energy. Without ozone, ultraviolet rays (UVA) would be much more powerful and would jeopardize our very health.

The famous ozone hole

For millions of years, ozone has therefore performed the function of protection towards the Earth, but in the last two centuries the industrialization of human societies has altered the current balance. Air pollution caused by factories, cars, heating (and refrigeration) systems and various industrial processes is in fact worsening what is called the "ozone hole", which in reality is not a real hole, but a thinning of the layer. 'ozone which, thus weakened, is able to filter much less solar radiation. The terminology of the "hole" depends on the fact that above the polar regions, normally less exposed to solar radiation, the layer has become so thin that it appears almost invisible.