Today, perhaps, you will not meet a person who would not hear about the problem of the ozone layer of the planet. Many myths, conjectures, and various hypotheses are circulated by the media. But here is what it is and where ozone came from on Earth, few remember. Let's try to understand this issue.
A bit of history
The physicist from the Netherlands, Martin van Marum, is considered the discoverer of ozone. In 1785, when an electric discharge was passed through a flask with air, he received odor gas. But he was described by a chemist from Germany H.F. Schonbein only in 1840. He called gas ozone, which means “smelling” in Greek. Thus, an analogy was drawn with the smell emitted by him. But where ozone came from in the atmosphere of the planet, it became known much later.
Two oxygen atoms and one more
The allotropic modification of oxygen, which consists of three atoms, is called ozone in chemistry. It can be described as a slightly bluish gas with a pronounced smell under normal conditions. When cooled, it first turns into a blue liquid (indigo), and upon transition to the solid state it forms crystals of dark blue or almost black. Ozone gas molecules in nature are very unstable, but as long as they exist, the substance has strong oxidizing properties.
Natural ozone
The well-known ozone layer of the planet (the ozonosphere) is stratospheric ozone. It is located at an altitude of 12-25 kilometers. It accounts for about 90% of all natural ozone. The remaining 10% is gas, which is lower. It is called tropospheric ozone. In addition to the different arrangement in the atmosphere, these two gases have completely different meanings.
Where did ozone come from in the ancient atmosphere
Blue gas appeared in the atmosphere of the planet as a result of a very complex photochemical reaction. Under the influence of the ultraviolet radiation of the Sun and cosmic radiation, during the decay of water molecules, a third atom joins the diatomic oxygen and an allotropic ozone atom is formed. This reaction takes place in the upper atmosphere of the planet today. In total, this gas occupies 0.6 ppm, which means that 0.6 centimeter of cubic ozone is contained in a cubic meter of atmosphere. That's where ozone came from in the atmosphere of our planet.
Ozone and life on the planet
At an altitude of 25 kilometers, this gas is concentrated in a very thin layer. But his role in life is very significant. Where ozone came from on Earth, we already know. It serves as a shield for ultraviolet radiation - disastrous for all living things. It is thanks to the absorption of this ultraviolet radiation, accompanied by the formation of ozone, that humanity is protected from death. The rate of ozone formation is on average equal to its decay rate. The importance of ozone for life is appreciated by humanity. And on September 16, the whole world celebrates the day of protection of the ozone layer of the planet.
Disastrous gas
In the Russian classification, ozone is classified as a substance of the highest hazard class. This strong oxidizing agent is very toxic to the human body. It does great harm, having a slow but destructive effect. With prolonged inhalation, the risk of developing cardiovascular disorders and respiratory tract infections increases sharply. The ability of ozone to react with cholesterol to form insoluble compounds leads to the development of atherosclerosis.
Ground gas
Where did the ozone in the Earth’s atmosphere, and in particular the surface gas, come from? The question is not simple. And there are several answer options. The main thing is that it is formed all the same as a result of photochemical reactions and exposure to radiation or high energies. As smog in cities, it is formed from its predecessors (nitrogen oxides, hydrocarbons) under the influence of temperature and solar radiation. And during the summer hot weather, the gas concentration rises with a pronounced daily rhythm. The maximum is reached at noon, and the minimum in the early morning hours. Increasing ozone concentration is promoted by descending air currents and high temperature.
Ozone or oxygen?
If oxygen is the source of life for all living things, then surface ozone is its death. Recent studies by biologists have confirmed its destructive effect on the lungs of our planet - on plants. Under the influence of ozone, the pores in the leaves of plants are reduced, and the processes of photosynthesis are suppressed. A computer model showed a 23% reduction in carbon dioxide consumption by plants. And this is a serious threat to life on the entire planet.
Ozone as a resource
Humanity has long been looking for ways to use in its activities all the resources that the Earth can provide. And no matter where the ozone in the atmosphere came from, it was no exception. The strongest oxidizing agent has found application in the sterilization of tools, in the disinfection of rooms and clothes, in the treatment of industrial, waste and drinking water. In promising industries, they replace chlorine with bleaching pulp. Development is underway in the use of liquid ozone as rocket fuel. And all women in the world know about cosmetics enriched with this gas.
Ozone shield and holes in it
For modern civilization, the question is not where ozone came from, but how to preserve the protective layer of this gas and not die in the stream of ultraviolet and cosmic radiation. And in order to understand how to save it, it is necessary to know the reasons for its destruction. We focus on the causes of the destruction of the ozone layer associated with anthropogenic activities:
- The development of astronautics and rocket science leads to a violation of the structure of the ozone layer, its ruptures and thinning.
- The development of ultra-high aviation contributes to the increase in the atmosphere of nitrogenous products of fuel combustion, which become ozone depleters in the atmosphere.
- The next reason is also associated with an increase in the concentration of nitrogen bases in the atmosphere and this is the use of nitrogen fertilizers in agricultural activities.
- Well-known freons, which are widely used in the manufacture of sprayers, refrigerators and air conditioners. In the upper atmosphere, they emit chlorine atoms through photochemical reactions. And they, in turn, destroy the ozone layer, connecting into chloride bases.