Where is the ozone layer? What is the ozone layer and why is its destruction harmful?

The ozonosphere is a layer of the atmosphere of our planet, which detains the hardest part of the ultraviolet spectrum. Some types of sunlight are detrimental to living organisms. Periodically, the ozonosphere becomes thinner, with gaps of various sizes appearing in it. Through the emergent holes on the surface of the Earth can freely penetrate dangerous rays. Where is the ozone layer? What can I do to save it? Discussion of these problems of geography and ecology of the Earth is devoted to the proposed article.

What is ozone?

Oxygen on Earth exists in the form of two simple gaseous compounds, is a part of water and a very large number of other common inorganic and organic substances (silicates, carbonates, sulfates, proteins, carbohydrates, fats). One of the more famous allotropic modifications of the element is a simple oxygen substance, its formula is O ₂ . The second modification of atoms is O (ozone). The formula for this substance is O ₃ . Triatomic molecules are formed with an excess of energy, for example, as a result of lightning discharges in nature. Next, we will find out what the ozone layer of the Earth is, why its thickness is constantly changing.

Ozone under normal conditions is a blue gas with a sharp, specific flavor. The molecular weight of the substance is 48 (for comparison, Mr _(air) = 29). The smell of ozone resembles a thunderstorm, because after this natural phenomenon of O ₃ molecules in the air becomes larger. The concentration increases not only where the ozone layer is located, but also close to the surface of the Earth. This reactive substance is toxic to living organisms, but dissociates rapidly (disintegrates). In the laboratory and industry, special devices were created-ozonizers-to pass electrical discharges through air or oxygen.

What is the ozone layer?

O ₃ molecules have high chemical and biological activity. The addition of a third atom to diatomic oxygen is accompanied by an increase in the energy reserve and instability of the compound. Ozone breaks down easily into molecular oxygen and an active particle that energetically oxidizes other substances and kills microorganisms. But more often than not, the questions connected with the smelling compound relate to its accumulation in the atmosphere above the Earth. What is the ozone layer and why is its destruction harmful?

Directly near the surface of our planet there is always a certain amount of O ₃ molecules, but with a height the concentration of the compound increases. The formation of this substance takes place in the stratosphere due to the ultraviolet radiation of the Sun, which carries a large amount of energy.

Ozonosphere

There is a region of space above the Earth where ozone is much larger than that of the surface. But on the whole, the shell consisting of O ₃ molecules is thin and discontinuous. Where is the ozone layer of the Earth or the ozonosphere of our planet? The inconstancy of the thickness of this screen has often confused the researchers.

In the Earth's atmosphere there is always a certain amount of ozone, there are significant fluctuations in its concentration with height and by year. We will deal with these problems after we find out the exact location of the protective shield from the O ₃ molecules.

Where is the ozone layer of the Earth?

A marked increase in the content of ozone molecules begins at a distance of 10 km and remains to 50 km above the Earth. But the amount of matter that is in the troposphere is not a screen yet. As the distance from the earth's surface increases, the density of ozone increases. The maximum values fall on the stratosphere, its area at an altitude of 20 to 25 km. Here, the O ₃ molecule is 10 times larger than that of the Earth's surface.

But why is the thickness, integrity of the ozone layer causing concern among scientists and ordinary people? The boom about the state of the protective screen broke out in the last century. The researchers found that the ozone layer of the atmosphere over Antarctica has become thinner. The main cause of the phenomenon - the dissociation of O ₃ molecules - was established. Destruction occurs as a result of a joint impact of a number of factors, leading among them is considered anthropogenic, associated with the activities of mankind.

Ozone holes

In the last 30-40 years, scientists have noted the appearance of gaps in the protective screen above the Earth's surface. The alarm of the scientific community was caused by reports that the ozone layer - the shield of the Earth - is intensely degrading. All media in the mid-1980s published reports of a "hole" over Antarctica. Researchers drew attention to the fact that this gap in the ozone layer increases in the spring. The main cause of damage growth was named artificial and synthetic substances - chlorofluorocarbons. The most common groups of these compounds are freons or refrigerants. There are more than 40 substances belonging to this group. They come from many sources, because the fields of application include food, chemical, perfume and other industries.

The composition of freons, in addition to carbon and hydrogen, includes halogen: fluorine, chlorine, and sometimes bromine. A large number of such substances are used as coolants in refrigerators, air conditioners. Freons themselves are stable, but at high temperatures and in the presence of active chemical agents enter into oxidation reactions. Among the products of the reaction, there may be compounds that are toxic to living organisms.

Freons and the ozone screen

Chlorofluorocarbons interact with O3 molecules and destroy the protective layer above the Earth's surface. First, the thinning of the ozonosphere was taken as a natural fluctuation in its thickness, which occurs constantly. But over time, holes like a "hole" over Antarctica were seen throughout the Northern Hemisphere. The number of such gaps has increased since the first observation, but in size they are smaller than over the ice continent.

Initially, scientists doubted that it was freons that caused the process of ozone depletion. These are substances with a large molecular mass. How can they reach the stratosphere, where is the ozone layer, if much heavier than oxygen, nitrogen and carbon dioxide? Observations of ascending currents in the atmosphere during a thunderstorm, as well as experiments carried out, proved the possibility of penetration of various particles with air to a height of 10-20 km above the Earth, where the boundary of the troposphere and stratosphere is located.

A variety of ozone destroyers

The ozone screen also receives nitrogen oxides arising from the combustion of fuel in the engines of supersonic aircraft and various types of spacecraft. Complement the list of substances from which the atmosphere, the ozone layer, the emissions of terrestrial volcanoes are destroyed. Sometimes the flow of gases and dust reaches a height of 10-15 kilometers and are carried hundreds of thousands of kilometers.

Smog over large industrial centers and megacities also contributes to the dissociation of O ₃ molecules in the atmosphere. The reason for the increase in the size of ozone holes is also considered to be the increase in the concentrations of so-called greenhouse gases in the atmosphere where the ozone layer is located. Thus, the global environmental problem of climate change is directly related to issues related to ozone depletion. The fact is that greenhouse gases contain substances that react with O ₃ molecules. Ozone dissociates, the oxygen atom causes oxidation of other elements.

The danger of losing the ozone shield

Were there gaps in the ozonosphere before flights into space, the appearance of freons and other pollutants of the atmosphere? The listed questions are controversial, but the conclusion suggests one: the ozone layer of the atmosphere must be studied and preserved from destruction. Our planet without a shield of O ₃ molecules loses its protection from hard cosmic rays of a certain length, absorbed by a layer of active substance. If the ozone screen is thin or missing, then the main life processes on Earth are endangered. Excessive ultraviolet radiation increases the risk of mutations in cells of living organisms.

Protection of the ozone layer

The lack of data on the thickness of the protective screen in the past centuries and millennia makes forecasts difficult. What will happen if the ozonosphere collapses completely? For several decades, doctors have noted an increase in the number of people affected by skin cancer. This is one of the diseases, which leads to excessive ultraviolet radiation.

In 1987, several countries joined the Montreal Protocol, which provided for the reduction and total ban on the production of chlorofluorocarbons. This was only one of the measures that will help preserve the ozone layer - the ultraviolet shield of the Earth. But freons are still produced by the industry and enter the atmosphere. Nevertheless, compliance with the Montreal Protocol has led to a reduction in ozone holes.

What can everyone do to conserve the ozonosphere?

Researchers suggest that a full restoration of the protective screen will take several more decades. This is in case if its intensive destruction is stopped, which causes many doubts. Greenhouse gases continue to flow into the atmosphere, launches of rockets and other space vehicles are launched, a fleet of aircraft in different countries is growing. This means that scientists still have to develop effective ways to protect the ozone shield from destruction.

At the everyday level, each person can also contribute. Ozone will be less decomposed if the air becomes cleaner, it will contain less dust, soot, toxic exhaust emissions of vehicles. To protect the fine ozonosphere, it is necessary to stop incineration of waste, to establish everywhere their safe disposal. Transport needs to be transferred to more environmentally friendly fuels, everywhere to conserve different types of energy resources.