OZONE AND ULTRAVIOLET AT THE EARTH’S ATMOSPHERE

Abstract

The appearance of the ozone layer (OL) in the Earth’s atmosphere and the associated processes of attenuation of the ultraviolet (UV) part of solar radiation reaching the surface are considered. It is shown that the role of OL in protecting living organisms from the destructive effects of exposure to the short-wavelength part of the insolation spectrum is immensely exaggerated. Ozone is generated by UV radiation below the ionosphere when oxygen molecules in the air are divided. When absorbed by UV rays, it is destroyed. Ozone exists for the longest time at minimum temperatures of the atmosphere. This circumstance and the increased density lead to the accumulation of O3 above the tropopause, where the OL is formed. The amount of simultaneously existing gas is extremely insignificant — about 10⁻⁶ air. It is this circumstance that makes it possible to estimate its contribution to the absorption of UV rays as vanishingly small. Compared with it, the scattering of rays by air molecules is incomparably more effective, although each single act of absorption of the middle part of the ultraviolet is several times greater than a single result of scattering. One can agree with the idea of the elimination of ozone molecules by reaction with freons and other gases containing halogens, including those of volcanic origin. It is also possible that it interacts with hydrogen, but H2 rather arising in the atmosphere, and not in the bowels of the Earth. But the processes of changing the OL, including the periodic formation of «ozone holes», do not pose any danger and are explained by natural phenomena, and not by human activity. A very expensive campaign to save the layer makes no sense. On the other hand, ground5level ozone concentration increases over time precisely under the influence of industrial emissions. In the cities of developed countries, the content of this poisonous gas already often exceeds permissible levels and it is time to take up more effective counteraction to its accumulation.

Keywords

• ozone layer
• ultraviolet radiation
• oxygen
• hydrogen