“We can, perhaps, say that the purpose of man is, as it were, to destroy his race, first making the globe uninhabitable.”

J.B. Lamarck.

Since the formation of a highly industrialized society, dangerous human intervention in nature has sharply increased, it has become more diverse and threatens to become a global danger to humanity. Hangs over the world real threat global ecological crisis, understood by the entire population of the planet. The real hope of preventing it lies in continuous environmental education and educating people.

It is possible to identify the main reasons leading to environmental disaster:

· pollution;

· poisoning of the environment;

· depletion of the atmosphere in oxygen;

· formation of ozone “holes”.

This message summarizes some literature data on the causes and consequences of ozone layer destruction, as well as ways to solve the problem of the formation of “ozone holes”.

Chemical and biological characteristics of ozone

Ozone is allotropic modification oxygen. Character chemical bonds in ozone causes its instability (through certain time ozone spontaneously transforms into oxygen: 2O 3 → 3O 2) and high oxidizing capacity. The oxidative effect of ozone on organic substances is associated with the formation of radicals: RH + O 3 → RО 2. +OH.

These radicals initiate radical chain reactions with bioorganic molecules (lipids, proteins, nucleic acids), which leads to cell death. Application of ozone for sterilization drinking water based on its ability to kill germs. Ozone is also important for higher organisms. Prolonged exposure to ozone-containing environments (such as physical therapy and quartz irradiation rooms) may cause severe violations nervous system. Therefore, ozone in large doses is toxic gas. The maximum permissible concentration in the air of the working area is 0.1 mg/m3.

There is very little ozone, which smells so wonderful during a thunderstorm, in the atmosphere - 3-4 ppm (per mille) - (3-4) * 10 -4%. However, its presence is extremely important for the flora and fauna of the planet. After all, life that originated in the ocean depths was able to “crawl” onto land only after the ozone shield was formed 600–800 million years ago. By absorbing biologically active solar ultraviolet radiation, it ensured its safe level on the surface of the planet. Life on Earth is unthinkable without the ozone layer, which protects all living things from harmful ultraviolet radiation Sun. The disappearance of the ozonosphere would lead to unpredictable consequences - an outbreak of skin cancer, the destruction of plankton in the ocean, mutations of flora and fauna. Therefore, it is so important to understand the causes of the ozone “hole” over Antarctica and the decrease in ozone levels in the Northern Hemisphere.

Ozone is formed in the upper stratosphere (40-50 km) during photochemical reactions involving oxygen, nitrogen, hydrogen and chlorine. Atmospheric ozone is concentrated in two areas - the stratosphere (up to 90%) and the troposphere. As for the tropospheric ozone layer distributed at an altitude of 0 to 10 km, it is precisely due to uncontrolled industrial emissions is getting bigger. In the lower stratosphere (10-25 km), where ozone is most abundant, the main role in seasonal and longer-term changes in its concentration is played by air mass transfer processes.

The thickness of the ozone layer over Europe is decreasing at a rapid pace, which cannot but worry the minds of scientists. For last year the thickness of the ozone “coating” was reduced by 30%, and the rate of deterioration of natural containment reached its highest level in the last 50 years. It has been established that chemical reactions that destroy ozone occur on the surface of ice crystals and any other particles trapped in the high stratosphere above the polar regions. What danger does this pose to humans?

Thin ozone layer(2-3 mm when distributed around Globe) cannot prevent the penetration of short-wave ultraviolet rays, which cause skin cancer and are dangerous to plants. So today because high activity Sunbathing has become less beneficial. In general, environmental centers should give recommendations to the population on how to act depending on the activity of the sun, but in our country there is no such center.

Associated with a decrease in the ozone layer climate change. It is clear that changes will occur not only in the area over which the ozone hole “stretches”. Chain reaction will entail changes in many deep processes of our planet. This does not mean that rapid global warming how they scare us in horror films. Still, this is too complex and time-consuming process. But other disasters may arise, for example, the number of typhoons, tornadoes, and hurricanes will increase.

It has been established that “holes” in the ozone layer appear over the Arctic and Antarctica. This is explained by the fact that acid clouds form at the poles, destroying the ozone layer. It turns out that ozone holes arise not from the activity of the sun, as is commonly believed, but from the daily activities of all the inhabitants of the planet, including you and me. Then the “acid gaps” shift, most often to Siberia.

Using new mathematical model It was possible to link together data from ground-based, satellite and aircraft observations with the levels of likely future emissions of ozone-depleting compounds into the atmosphere, the timing of their transport to Antarctica and weather in southern latitudes. Using the model, a forecast was obtained according to which the ozone layer over Antarctica will recover in 2068, and not in 2050, as was believed.

It is known that currently the level of ozone in the stratosphere over areas far from the poles is approximately 6% below normal. At the same time, in the spring, the ozone content over Antarctica can decrease by 70% relative to average annual value. New model makes it possible to more accurately predict the levels of ozone-depleting gases over Antarctica and their time dynamics, which determines the size of the ozone “hole”.

The use of ozone depleting substances is limited by the Montreal Protocol. It was believed that this would lead to a rapid “tightening” of the ozone hole. However, new research has shown that in reality the rate of decline will only become noticeable in 2018.

History of ozone research

The first observations of ozone date back to 1840, but the ozone problem received rapid development in the 20s of the last century, when special ground stations appeared in England and Switzerland.

An additional way to study the connections between ozone transfer and atmospheric stratification has been opened by aircraft soundings of atmospheric ozone and releases of ozone probes. New era marked by the appearance artificial satellites Earth, observing atmospheric ozone and providing a wealth of information.

In 1986, the Montreal Protocol was signed to limit the production and consumption of ozone-depleting substances that deplete the ozone layer. To date, 189 countries have joined the Montreal Protocol. Time limits have been established for the cessation of production of other ozone-depleting substances. According to model forecasts, if the Protocol is observed, the level of chlorine in the atmosphere will decrease by 2050 to the 1980 level, which could lead to the disappearance of the Antarctic “ozone hole”.

Reasons for the formation of the “ozone hole”

In summer and spring, ozone concentrations increase. It is always higher over the polar regions than over the equatorial ones. In addition, it changes on an 11-year cycle, coinciding with the solar activity cycle. All this was already well known when in the 1980s. Observations have shown that over Antarctica there is a slow but steady decrease in stratospheric ozone concentrations from year to year. This phenomenon is called the "ozone hole" (although there is no hole in own meaning this word, of course, did not exist).

Later, in the 90s of the last century, the same decrease began to occur over the Arctic. The phenomenon of the Antarctic “ozone hole” is not yet clear: whether the “hole” arose as a result of anthropogenic pollution of the atmosphere, or whether it is a natural geoastrophysical process.

Among the versions of the formation of ozone holes are:

influence of particles emitted during atomic explosions;

· flights of rockets and high-altitude aircraft;

· reactions of certain substances produced by chemical plants with ozone. These are primarily chlorinated hydrocarbons and especially freons - chlorofluorocarbons, or hydrocarbons, in which all or most hydrogen atoms are replaced by fluorine and chlorine atoms.

Chlorofluorocarbons are widely used in modern household and industrial refrigerators (that’s why they are called “freons”), in aerosol cans, as dry cleaning agents, for extinguishing fires in transport, as foaming agents, and for the synthesis of polymers. World production of these substances has reached almost 1.5 million tons/year.

Being highly volatile and quite resistant to chemical influences, chlorofluorocarbons enter the atmosphere after use and can remain in it for up to 75 years, reaching the height of the ozone layer. Here under the influence sunlight they decompose, releasing atomic chlorine, which serves as the main “disturber of order” in the ozone layer.

The widespread use of fossil resources is accompanied by the release into the atmosphere of large masses of various chemical compounds. Most anthropogenic sources are concentrated in cities, occupying only a small part of the territory of our planet. As a result of the movement of air masses from the leeward side big cities a multi-kilometer plume of pollution is formed.

The sources of air pollution are:

1) Road transport. It can be assumed that the contribution of transport to air pollution will increase as the number of cars increases.

2) Industrial production. The basic products of basic organic synthesis are ethylene (almost half of all organic matter), propylene, butadiene, benzene, toluene, xylenes and methanol. Emissions from chemical and petrochemical industry enterprises contain a wide range of pollutants: components of feedstock, intermediate, by-products and target synthesis products.

3) Aerosols. Chlorofluorocarbons (freons) are widely used as volatile components (propellants) in aerosol packages. For these purposes, about 85% of freons were used and only 15% in refrigeration units and artificial climate units. The specificity of using freons is such that 95% of their quantity enters the atmosphere 1-2 years after production. It is believed that almost the entire amount of freon produced must sooner or later enter the stratosphere and be included in the catalytic cycle of ozone destruction.

The earth's crust contains various gases in a free state, sorbed by different rocks and dissolved in water. Some of these gases reach the Earth's surface through deep faults and cracks and diffuse into the atmosphere. About the existence of hydrocarbon respiration earth's crust indicates an increased content of methane in the surface layer of air above oil and gas basins compared to the global background level.

Studies have shown that the gases of Nicaragua's volcanoes contain noticeable amounts of HF. Analysis of air samples taken from the crater of the Masaya volcano also showed the presence of freons in them along with other organic compounds. Halocarbons are also present in gases from hydrothermal vents. These data required evidence that the detected hydrofluorocarbons did not have anthropogenic origin. And such evidence was obtained. Freons were found in air bubbles Antarctic ice 2000 years old. NASA specialists undertook a unique study of the air from a hermetically sealed lead coffin, discovered in Maryland and reliably dated to the 17th century. Freons were also found in it. Another confirmation of the existence of a natural source of freons was “raised” from the seabed. CFCl 3 was found in water recovered in 1982 from depths of more than 4,000 meters in the equatorial Atlantic Ocean, at the bottom of the Aleutian Trench and at a depth of 4,500 meters off the coast of Antarctica.

Misconceptions about ozone holes

There are several widespread myths regarding the formation of ozone holes. Despite their unscientific nature, they often appear in the media - sometimes out of ignorance, sometimes supported by conspiracy theorists. Some of them are listed below.

1) The main ozone destroyers are freons. This statement is true for middle and high latitudes. In the rest, the chlorine cycle is responsible for only 15-25% of ozone loss in the stratosphere. It should be noted that 80% of chlorine is of anthropogenic origin. That is, human intervention greatly increases the contribution of the chlorine cycle. Before human intervention, the processes of ozone formation and destruction were in equilibrium. But freons emitted by human activity have shifted this balance towards a decrease in ozone concentration. The mechanism of ozone destruction in the polar regions is fundamentally different from that at higher latitudes; the key stage is the conversion of inactive forms of halogen-containing substances into oxides, which occurs on the surface of particles of polar stratospheric clouds. And as a result, almost all ozone is destroyed in reactions with halogens (chlorine is responsible for 40-50% and bromine is responsible for about 20-40%).

2) Freons are too heavy to reach the stratosphere .

It is sometimes argued that since freon molecules are much heavier than nitrogen and oxygen, they cannot reach the stratosphere in significant quantities. However, atmospheric gases are completely mixed, rather than separated or sorted by weight. Estimates of the required time for the diffusion stratification of gases in the atmosphere require times of the order of thousands of years. Of course, in a dynamic atmosphere this is impossible. Therefore, even such heavy gases as inert gases or freons are evenly distributed in the atmosphere, including reaching the stratosphere. Experimental measurements their concentrations in the atmosphere confirm this. If the gases in the atmosphere did not mix, then such heavy gases from its composition as argon and carbon dioxide would form a layer several tens of meters thick on the surface of the Earth, which would make the surface of the Earth uninhabitable. Fortunately this is not the case.

3) The main sources of halogens are natural, not anthropogenic

Sources of chlorine in the stratosphere

It is believed that natural sources of halogens, such as volcanoes or oceans, are more significant for the process of ozone destruction than those produced by humans. Without questioning the contribution of natural sources to the overall balance of halogens, it should be noted that they generally do not reach the stratosphere due to the fact that they are water-soluble (mainly chloride ions and hydrogen chloride) and are washed out of the atmosphere, falling as rain on the ground.

4) The ozone hole must be located above the sources of freons

Dynamics of changes in the size of the ozone hole and ozone concentration in Antarctica by year.

Many people do not understand why the ozone hole forms in Antarctica when the main emissions of CFCs occur in the Northern Hemisphere. The fact is that freons are well mixed in the troposphere and stratosphere. In view of the small reactivity they are practically not consumed in the lower layers of the atmosphere and have a lifespan of several years or even decades. Therefore, they easily reach the upper layers of the atmosphere. The Antarctic “ozone hole” does not exist forever. It appears at the end of winter - beginning of spring.

The reasons why the ozone hole forms in Antarctica are related to the local climate. Low temperatures Antarctic winters lead to the formation of a polar vortex. The air inside this vortex moves mainly along closed trajectories around South Pole. At this time, the polar region is not illuminated by the Sun, and ozone does not arise there. With the arrival of summer, the amount of ozone increases and returns to its previous level. That is, fluctuations in ozone concentration over Antarctica are seasonal. However, if we trace the yearly averaged dynamics of changes in ozone concentration and the size of the ozone hole over the past decades, then there is a strictly defined tendency for ozone concentration to fall.

5) Ozone is only destroyed over Antarctica

Dynamics of changes in the ozone layer over Arosa, Switzerland

This is not true; ozone levels are also falling throughout the atmosphere. This is shown by the results of long-term measurements of ozone concentrations in different parts of the planet. You can look at the graph of changes in ozone concentration over Arosa (Switzerland).

Ways to solve problems

To begin global recovery, it is necessary to reduce the access to the atmosphere of all substances that very quickly destroy ozone and are stored there for a long time. People need to understand this and help nature start the process of restoring the ozone layer; in particular, new forest plantings are needed.

To restore the ozone layer, it needs to be recharged. At first, for this purpose, it was planned to create several ground-based ozone factories and “throw” ozone into the upper layers of the atmosphere on cargo planes. However, this project (probably it was the first project to “treat” the planet) was not implemented. A different way is proposed by the Russian consortium Interozon: producing ozone directly in the atmosphere. In the near future, together with the German company Daza, it is planned to raise balloons with infrared lasers to a height of 15 km, with the help of which they can produce ozone from diatomic oxygen. If this experiment turns out to be successful, in the future it is planned to use the experience of the Russian orbital station"Mir" and create several space platforms with energy sources and lasers at an altitude of 400 km. Laser beams will be directed into the central part of the ozone layer and will constantly replenish it. The energy source can be solar panels. Astronauts on these platforms will only be required for periodic inspections and repairs.

Time will tell whether the grandiose peace project will be realized.

Taking into account the emergency of the situation, it seems necessary:

Expand the complex of theoretical and experimental research on the problem of preserving the ozone layer;

Create an International Fund for the Preservation of the Ozone Layer through active means;

Organize an International Committee to develop a strategy for the survival of humanity in extreme conditions.

References

1. (ru -).

2. ((cite web - | url = http://www.duel.ru/200530/?30_4_2 - | title = “Duel” Is it worth it? - | accessdate = 07/3/2007 - | lang = ru - ) )

3. I.K.Larin. The ozone layer and the Earth's climate. Errors of the mind and their correction.

4. National Academy of SciencesHalocarbons: Effects on Stratospheric Ozone. - 1976.

5. Babakin B. S. Refrigerants: history of appearance, classification, application.

6. Magazine "Ecology and Life". Article by E.A. Zhadina, candidate of physical and mathematical sciences.

Ozone is found in waste gases emitted by industries and is a hazardous chemical. It is a very active element and can cause corrosion of structural elements of all kinds of structures. However, in the atmosphere, ozone is converted into an invaluable assistant, without which life on Earth could simply not exist.

The stratosphere is the one that follows the one in which we live. Its upper part is covered by ozone, its content in this layer is 3 molecules per 10 million other air molecules. Even though the concentration is very low, ozone performs the most important function- it is able to block the path of ultraviolet rays coming from space simultaneously with sunlight. Ultraviolet rays negatively affect the structure of living cells and can cause the development of diseases such as eye cataracts, cancer and other serious ailments.

The basis of protection is next principle. At the moment when oxygen molecules meet in the path of ultraviolet rays, a reaction occurs that splits them into 2 oxygen atoms. The resulting atoms combine with unsplit molecules, creating ozone molecules consisting of 3 oxygen atoms. When they encounter ozone molecules, the latter break them down into three oxygen atoms. The moment the molecules split is accompanied by the release of heat, and they no longer reach the Earth’s surface.

Ozone holes

The process of converting oxygen into ozone and vice versa is called the oxygen-ozone cycle. Its mechanism is balanced, however, its dynamism changes depending on the intensity of solar radiation, season and natural disasters, in particular. Scientists have concluded that human activity negatively affects its thickness. Depletion of the ozone layer has been recorded over last decades in many places. IN in some cases he disappeared completely. How to reduce negative impact person for the specified cycle?

Ozone holes occur due to the fact that the process of destruction of the protective layer is much more intense than its generation. This is explained by the fact that in the process of human life the atmosphere is polluted by various ozone-depleting compounds. These are, first of all, chlorine, bromine, fluorine, carbon and hydrogen. Scientists believe that chlorofluorocarbon compounds pose a major threat to the ozone layer. They are widely used in refrigeration, industrial solvents, air conditioners and aerosol cans.

Chlorine, reaching the ozone layer, interacts with it. Chemical reaction generates an oxygen molecule. When chlorine oxide meets a free oxygen atom, another interaction occurs, as a result of which chlorine is released and an oxygen molecule appears. Subsequently, the chain repeats itself, because chlorine is not able to leave the atmosphere or fall to the ground. Ozone holes are a consequence of the fact that the concentration of this element decreases due to its accelerated breakdown when foreign foreign components appear in its layer.

Locations

The largest ozone holes have been found over Antarctica. Their size practically corresponds to the area of ​​the continent itself. This area is practically uninhabited, but scientists are concerned that the breach could spread to other heavily populated areas of the planet. This is fraught with the death of the Earth.

To prevent a decrease in the ozone layer, it is necessary first of all to reduce the amount of destructive substances emitted into the atmosphere. In 1987, the Montreal Treaty was signed in 180 countries, which provides for a gradual reduction in emissions of substances containing chlorine. Now the ozone hole is decreasing, and scientists hope that the situation will be completely corrected by 2050.

The Earth's atmosphere contains several layers located at different heights. One of the most important is the ozone layer, located in the stratosphere. In order to figure out what the ozone hole is, you need to understand the function of this layer and the importance of its existence for life on the planet.

Description

The height of the ozone layer varies depending on the temperature regime of a particular area, for example, in the tropics it is in the range between 25 and 30 km, and at the poles - from 15 to 20 km. Ozone gas is created when oxygen molecules are exposed to solar radiation. The process of ozone dissociation leads to the absorption of most of the dangerous ultraviolet radiation emitted by the Sun.
The thickness of the layer is usually measured in Dobson units, each of which is equal to an ozone layer of 10 micrometers, subject to normal pressure and temperature. The minimum thickness below which the layer ceases to exist is considered to be 220 units. Dobson. The presence of the ozone layer was established by French physicists Charles Fabry and Henri Buisson at the beginning of the twentieth century using spectroscopic analysis.

Ozone holes

There are many versions about what exactly provokes the thinning of the planet’s ozone layer. Some scientists blame anthropogenic factors for this, while others consider it a natural process. Ozone holes are a decrease or complete disappearance of this gas from the stratosphere. This phenomenon was first recorded in 1985; it was located over an area of ​​about 1 thousand sq km in the Antarctic region.
The appearance of this hole was cyclical; it appeared in August and disappeared in December. At the same time, another, slightly smaller hole appeared in the Arctic region. With the development of technology, it has become possible to record the formation of gaps in the ozone layer in real time, and now scientists can confidently say that there are several hundred of them on the planet. The largest ones are located at the poles.

Causes and consequences of ozone holes

There is a theory that ozone holes occur due to natural causes. According to it, since the conversion of oxygen into ozone occurs as a result of exposure to solar radiation, in its absence during the polar winter this gas is not produced. During a long night, the ozone already formed due to its large mass falls into the lower layers of the atmosphere, where it is destroyed by pressure. This version perfectly explains the appearance of holes over the poles, but does not in any way clarify the formation of their large-scale analogues over the territories of Kazakhstan and Russia, where polar nights are not observed.
IN lately scientific community it was agreed that there are both natural and provoked human activity causes of ozone layer ruptures. The anthropogenic factor includes an increase in the concentration of certain chemicals in the Earth's atmosphere. Ozone is destroyed by reactions with chlorine, hydrogen, bromine, hydrogen chloride, nitrogen monoxide, methane, as well as freon and its derivatives. The causes and consequences of ozone holes have not yet been fully established, but almost every year brings new discoveries in this area.

Why are ozone holes dangerous?

Ozone absorbs extremely dangerous solar radiation, preventing it from reaching the surface of the planet. When the layer of this gas becomes thinner, everything on Earth is exposed to normal radioactive radiation. This provokes the growth of cancer, mainly localized on the skin. For plants, the disappearance of ozone is also destructive; various genetic mutations and a general decrease in vitality. Recently, humanity has become increasingly aware of the dangers of ozone holes for life on Earth.

Conclusion

Realizing the danger of ozone destruction, the international community took a number of measures aimed at reducing negative impact to the atmosphere. In 1987, a protocol was signed in Montreal that obliges to minimize the use of freon in industry, since it is this gas that provokes the formation of holes outside the polar regions. However, the freon already released into the atmosphere will take about a hundred years to decompose, so the number of ozone holes in the Earth’s atmosphere is unlikely to decrease in the near future.

This huge hole in the earth's ozone layer was discovered in 1985; it appeared over Antarctica. It is more than one thousand kilometers in diameter and approximately nine million kilometers square in area.

Every year in the month of August, the hole disappears and it happens as if this huge ozone hole never existed.

Ozone hole - definition

An ozone hole is a decrease or complete absence of ozone concentration in the Earth's ozone layer. According to the report of the World Meteorological Organization and the generally accepted theory in science, a significant decrease in the ozone layer is caused by an ever-increasing anthropogenic factor - the release of bromine- and chlorine-containing freons.

There is another hypothesis, according to which the very process of formation of holes in the ozone layer is natural and in no way connected with the results of the activities of human civilization.

A combination of factors causes a decrease in ozone concentration in the atmosphere. One of the main ones is the destruction of ozone molecules during reactions with various substances natural and anthropogenic origin, as well as the lack of sunlight and radiation during the polar winter. This includes the polar vortex, which is particularly stable and prevents the penetration of ozone from the circumpolar latitudes, and the resulting stratospheric polar clouds, the surface of which particles act as a catalyst for the ozone decay reaction.

These factors are typical for Antarctica, and in the Arctic the polar vortex is much weaker due to the fact that there is no continental surface there. The temperature here is higher by some amount, unlike Antarctica. Polar stratospheric clouds are less common in the Arctic and tend to break up in early autumn.

What is Ozone?

Ozone is poisonous substance which is harmful to humans. In no large quantities it has a very pleasant smell. To make sure of this, you can take a walk in the forest during a thunderstorm - we’ll enjoy it in time fresh air, but later you will feel very bad.

IN normal conditions There is practically no ozone at the bottom of the Earth's atmosphere - this substance is present in large quantities in the stratosphere, starting somewhere around 11 kilometers above the earth and extending to 50-51 kilometers. The ozone layer lies right at the very top, that is, approximately 51 kilometers above the earth. This layer absorbs the deadly rays of the sun and thereby protects our lives and not only ours.

Before the discovery of ozone holes, ozone was considered a substance that poisons the atmosphere. They believed that the atmosphere was full of ozone and that it was the main culprit “ greenhouse effect”, with which you need to do something.

In the present, humanity, on the contrary, is trying to take steps to restore the ozone layer, since the ozone layer is becoming thinner throughout the Earth, and not just over Antarctica.

There are many hypotheses trying to explain the decline in ozone concentrations. The reasons for its fluctuations in the Earth's atmosphere are related to:

• with dynamic processes occurring in the Earth’s atmosphere (internal gravitational waves, Azores anticyclone, etc.);
• · with the influence of the Sun (fluctuations in its activity);
• with volcanism as a consequence geological processes(outflow of freons from volcanoes involved in the destruction of the ozone layer, variations magnetic field Land, etc.);
• · with natural processes occurring in the upper shells of the Earth, including the activity of nitrogen-producing microorganisms, sea currents (El Niño phenomenon), forest fires, etc.;
• · with the anthropogenic factor associated with human economic activity, when significant volumes of ozone-depleting compounds are produced into the atmosphere.

In recent decades, the impact of anthropogenic factors has increased sharply, which has led to the emergence environmental problems, which were unexpectedly turned into global ones by people themselves: the greenhouse effect, acid rain, destruction of forests, desertification of territories, environmental pollution harmful substances, abbreviations biological diversity planets.

Some scientists believe that it is economic activity humans largely increased the share of the halogen decay pathway of stratospheric ozone, which provoked the occurrence of ozone holes.

The 1987 Montreal Protocol banned the production of refrigerants, which have been used to preserve food for the past half century, not only making human life more comfortable, but also saving the lives of many millions of people suffering from food shortages. As cheap refrigerants were banned, underdeveloped countries were unable to purchase expensive refrigerants. Therefore, they cannot store the agricultural products they produce. Expensive imported equipment developed in the countries of the initiators of the “fight against ozone holes” brings them considerable income. The ban on refrigerants has contributed to an increase in mortality in the poorest countries.

Today we can say with confidence that there is no strictly scientifically proven evidence regarding the destructive effect of artificially created chlorofluocarbon molecules on the ozone layer of the planet. But in scientific community The prevailing point of view is that in the second half of the 20th century, the reason for the decrease in the thickness of the ozone layer was the anthropogenic factor, which in the form of the release of chlorine- and bromine-containing freons led to a significant thinning of the ozone layer.

Freons are fluorine-containing derivatives of saturated hydrocarbons (mainly methane and ethane), used as refrigerants in refrigeration machines. In addition to fluorine atoms, freon molecules usually contain chlorine atoms, less often bromine. More than 40 different freons are known. Most of them are produced by industry.

Freon 22 (Freon 22) - belongs to substances of the 4th hazard class. When exposed to temperatures above 400°C, it can decompose to form highly toxic products: tetrafluoroethylene (4th hazard class), hydrogen chloride (2nd hazard class), hydrogen fluoride (1st hazard class).

Thus, the data obtained strengthened the conclusion of many (but not all!) researchers that the observed loss of ozone in the middle and high latitudes is mainly due to anthropogenic chlorine- and bromine-containing compounds.

But according to other ideas, the formation of “ozone holes” is largely a natural, periodic process, not associated exclusively with harmful effects human civilization. This point of view today is not shared by many, not only because they lack arguments, but because it turned out to be more profitable to follow in the wake of “global utopias.” Many scientists, lacking funds for scientific research, have become and are becoming victims of grants to justify the ideas of “global environmental chauvinism” and the guilt of progress in this.

As G. Kruchenitsky points out, A. Khrgian, Russia’s leading ozone specialist, was practically the first to draw attention to the fact that the formation and disappearance of ozone holes in the northern hemisphere correlates with atmospheric-dynamic, and not chemical processes. The ozone content can change by several tens of percent within two to three days. That is, it is not a matter of ozone-depleting substances, but of the dynamics of the atmosphere itself.

E. Borisenkov, a prominent specialist in the field of atmospheric studies, based on processing data from nine Western European stations over twenty-three years, established a correlation between 11-year cycles of solar activity and changes in ozone in the Earth’s atmosphere.

The causes of ozone holes are mostly associated with anthropogenic sources of compounds penetrating into the stratospheric layer of the Earth’s atmosphere. However, there is one catch. It lies in the fact that the main sources of ozone-depleting compounds are not located in the polar (southern and northern) latitudes, but are concentrated closer to the equator and are almost entirely located in the northern hemisphere. While the most frequent phenomena of thinning the thickness of the ozone layer (the actual appearance of ozone holes) are observed in Antarctica ( southern hemisphere) and less frequently in the Arctic zone.

That is, sources of ozone-depleting compounds must be quickly and well mixed in the Earth's atmosphere. At the same time, they quickly leave the lower layers of the atmosphere, where their reactions with the participation of ozone should also be observed. To be fair, it should be noted that there is significantly less ozone in the troposphere than in the stratosphere. In addition, the “lifetime” of these compounds can reach several years. Therefore, they can reach the stratosphere under conditions of dominant vertical movements of air masses and heat. But here comes the difficulty. Since the main movements associated with heat and mass transfer (heat + transferred air mass), are carried out precisely in the troposphere. And since the air temperature is already constant at an altitude of 11-10 km and is about -50? C, then this heat and mass transfer from the tropospheric layer to the stratospheric layer should be slowed down. And the participation of anthropogenic sources that destroy the ozone layer may not be as significant as is still believed.

The next fact that can reduce the role of the anthropogenic factor in the destruction of the Earth's ozone layer is the appearance of ozone holes, mostly in spring or winter time. But this, firstly, contradicts the assumption about the possibility of rapid mixing of ozone-depleting compounds in the Earth’s atmosphere and their penetration into the stratosphere high concentration ozone. Secondly, the anthropogenic source of ozone-depleting compounds is constantly active. Consequently, it is difficult to explain the reason for the appearance of ozone holes in spring and winter, and even in polar latitudes, by an anthropogenic cause. But the presence of polar winters and the natural decrease solar radiation in winter explains satisfactorily natural cause the occurrence of ozone holes over Antarctica and the Arctic. For example, ozone concentrations in the Earth's atmosphere in summer vary from 0 to 0.07%, and in winter from 0 to 0.02%.

In Antarctica and the Arctic, the mechanism of ozone destruction is fundamentally different from higher latitudes. Here, the conversion of inactive forms of halogen-containing substances into oxides mainly occurs. The reaction takes place on the surface of particles of polar stratospheric clouds. As a result, almost all ozone is destroyed in reactions with halogens. At the same time, chlorine is responsible for 40-50% and bromine is responsible for about 20-40%.

With the arrival of the polar summer, the amount of ozone increases and returns to its previous level. That is, fluctuations in ozone concentration over Antarctica are seasonal. Everyone admits this. But if, nevertheless, earlier supporters of anthropogenic sources of ozone-depleting compounds were inclined to claim that a steady dynamics of decrease in ozone concentration was observed during the year, then later this dynamics turned out to be the opposite. Ozone holes have begun to shrink. Although, in their opinion, restoration of the ozone layer should take several decades. Since it was believed that a huge volume of freons from anthropogenic sources had accumulated in the atmosphere, which have a lifetime of tens, and even hundreds of years. Therefore, the ozone hole should not be expected to close before 2048. As we see, this forecast did not come true. But drastic efforts were made to reduce freon production volumes.

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