How are ozone holes formed? The largest ozone hole Ozone holes are formed as a result of anthropogenic emissions.

The earth is arranged in such a way that its unique ecosystem is preserved. These purposes are served by the layers of the atmosphere, which cover the planet from the penetration of ultraviolet rays, radiation, and space debris. In nature, everything is perfect, and interference in its structure leads to various cataclysms and violation of the established order. At the end of the 20th century, a clear problem emerged that affects all of humanity. The ozone hole formed in the Antarctic region and attracted the attention of scientists from all over the world. The critical situation of ecology was aggravated by another serious problem.

It was found that in the ozone layer surrounding the earth's surface, a gap was formed, more than a thousand kilometers in size. Through it, radiation enters, adversely affecting people, animals and vegetation. Ozone holes and thinning of the gas envelope were later discovered in several more places, causing a stir in public circles.

The essence of the problem

Ozone is formed from oxygen, which is affected by ultraviolet rays. Due to this reaction, the planet is shrouded in a layer of gas through which radiation cannot enter. This layer is located at an altitude of 25-50 kilometers above the surface. The thickness of the ozone is not very large, but it is quite enough for all life to exist on the planet.

What is the ozone hole, learned in the 80s of the last century. This sensational discovery was made by British scientists. In places of ozone destruction, gas is not completely absent, its concentration decreases to a critical level of 30%. The gap formed in the stratosphere layer passes ultraviolet rays to the ground, which can burn living organisms.

The first such hole was discovered in 1985. Its location is Antarctica. The peak time when the ozone hole expanded was August, and by winter the gas condensed and practically closed the hole in the stratospheric layer. Critical points in height are located at a distance of 19 kilometers from the ground.

The second ozone hole appeared over the Arctic. Its dimensions were much smaller, but otherwise there was a striking resemblance. Critical heights and time of disappearance coincided. Currently, ozone holes appear in different places.

How does the thinning of the ozone layer occur?

Scientists attribute the emergence of a problem with the thinning of the ozone layer to natural phenomena occurring at the poles of the globe. According to their theory, during the long polar nights, the sun's rays do not reach the earth, and ozone cannot be formed from oxygen. In this regard, clouds with a high content of chlorine are formed. It is he who destroys the gas so necessary to protect the planet.

The earth was going through a period of volcanic activity. It also had a detrimental effect on the thickness of the ozone layer. Emissions into the atmosphere of combustion products destroyed the already thin layer of the stratosphere. The release of freons into the air is another reason for the thinning of the protective layer of the earth.

The ozone hole disappears as soon as the sun begins to shine and interact with oxygen. Due to air currents, the gas rises and fills the resulting void. This theory proves that ozone circulation is constant and inevitable.

Other causes of ozone holes

Despite the fact that chemical processes play a dominant role in the formation of ozone holes, human impact on nature creates the main prerequisites. Naturally occurring chlorine atoms are not the only substances harmful to ozone. The gas is also destroyed by the action of hydrogen, bromine and oxygen. The reasons for the appearance of these compounds in the air lie in human activities on the planet. The preconditions are:

• operation of plants and factories;
• lack of treatment facilities;
• atmospheric emissions from thermal power plants;

Nuclear explosions had a detrimental effect on the integrity of the atmosphere. Their consequences still affect the ecology of the planet. At the time of the explosion, a huge amount of nitrogen oxides is formed, which, rising, destroy the gas that protects the earth from radiation. Over 20 years of testing, more than three million tons of this substance have entered the atmosphere.

Jet planes have a devastating effect on the ozone layer. When fuel is burned in turbines, nitrogen oxides are thrown out, they directly enter the atmosphere and destroy gas molecules. Currently, out of a million tons of emissions of this substance, a third is accounted for by aircraft.

It would seem that mineral fertilizers are harmless and useful, but in fact they also adversely affect the atmosphere. When interacting with bacteria, they are processed into nitrous oxide, and then, under the influence of chemical reactions, change their shape and become oxides.

Thus, the ozone hole is a product not only of natural phenomena, but also of human impact on the environment. Rough decisions can lead to unexpected results.

Why is the disappearance of the ozone layer around the planet dangerous?

The sun is the source of heat and light for everything on the planet. Animals, plants and man flourish thanks to its life-giving rays. This was noted by the people of the ancient world, who considered the Sun-God to be the main idol. But the luminary can also cause the death of life on the planet.

Through the ozone holes formed under the influence of man and nature in tandem, solar radiation can fall on the earth and incinerate everything that was once grown. The detrimental effects on humans are obvious. Scientists have found that if the protective gas or its layer becomes thinner by one percent, then seven thousand more cancer patients will appear on earth. First of all, the skin of people will suffer, and then other organs.

The consequences of the formation of ozone holes affect not only humanity. Vegetation suffers, as well as wildlife and inhabitants of the deep sea. Their mass extinction is a direct consequence of the processes taking place on the sun and in the atmosphere.

Ways to solve the problem

The reasons for the appearance of ozone holes in the atmosphere are varied, but come down to one essential fact: thoughtless human activity and new technological solutions. Freons that enter the atmosphere and destroy its protective layer are a product of the combustion of various chemicals.

To stop these processes, fundamentally new scientific developments are needed that will allow production, heating, production and flight without the use of nitrogen, fluorine and bromine, as well as their derivatives.

The emergence of the problem is associated with careless production and agricultural activities. It's time to think:

• on the installation of treatment facilities on smoking chimneys;
• on the replacement of chemical fertilizers with organic ones;
• on the transition of transport to electricity.

Quite a lot has been done over the past sixteen years, since 2000. Scientists managed to achieve amazing results: the size of the ozone hole over Antarctica has decreased by an area equal to the territory of India.

The consequences of negligent and inattentive attitude to the environment are already making themselves felt. In order not to aggravate the situation even more, it is necessary to deal with the problem at the global level.

This huge hole in the ozone layer of the earth was discovered in 1985, it appeared over Antarctica. In diameter, it is more than one thousand kilometers, and in area - about nine million kilometers squared.

Every year in the month of August, the hole disappears and it happens as if this huge ozone gap 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 theory generally accepted 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 activity of human civilization.

A decrease in the concentration of ozone in the atmosphere causes a combination of factors. One of the main ones is the destruction of ozone molecules during reactions with various substances of natural and anthropogenic origin, as well as the absence 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 latitudes of the polar region, and the resulting stratospheric polar clouds, the surface of the particles of which acts 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. The temperature here is higher by a certain amount, in contrast to Antarctica. Polar stratospheric clouds are less common in the Arctic and tend to break up in early autumn.

What is Ozone?

Ozone is a poisonous substance that is harmful to humans. In small quantities, it has a very pleasant smell. To be convinced of this, you can take a walk in the forest in a thunderstorm field - at the time we will enjoy the fresh air, but later we will feel very unwell.

Under normal conditions, there is practically no ozone below the Earth's atmosphere - this substance is present in large quantities in the stratosphere, starting somewhere around 11 kilometers above the earth and extending up to 50-51 kilometers. The ozone layer lies just at the top of the catfish, that is, approximately 51 kilometers above the earth. This layer absorbs the deadly rays of the sun and thus protects our and not only our lives.

Before the discovery of ozone holes, ozone was considered a substance that poisoned the atmosphere. It was believed that the atmosphere was filled with ozone and that it was he who was the main culprit of the "greenhouse effect", with which something had to be done.

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

Ozone holes - "children" of stratospheric vortices

Although there is little ozone in the modern atmosphere - no more than one three millionth of the rest of the gases - its role is extremely large: it delays hard ultraviolet radiation (the short-wave part of the solar spectrum), which destroys proteins and nucleic acids. In addition, stratospheric ozone is an important climatic factor that determines short-term and local weather changes.

The rate of ozone destruction reactions depends on catalysts, which can be both natural atmospheric oxides and substances released into the atmosphere as a result of natural disasters (for example, powerful volcanic eruptions). However, in the second half of the last century, it was discovered that substances of industrial origin can also serve as catalysts for ozone destruction reactions, and humanity was seriously worried ...

Ozone (O 3) is a relatively rare molecular form of oxygen, consisting of three atoms. Although there is little ozone in the modern atmosphere - no more than one three millionth of the rest of the gases - its role is extremely large: it delays hard ultraviolet radiation (the short-wave part of the solar spectrum), which destroys proteins and nucleic acids. Therefore, before the advent of photosynthesis - and, accordingly, free oxygen and the ozone layer in the atmosphere - life could exist only in water.

In addition, stratospheric ozone is an important climatic factor that determines short-term and local weather changes. By absorbing solar radiation and transferring energy to other gases, ozone heats the stratosphere and thereby regulates the nature of planetary thermal and circular processes throughout the atmosphere.

Unstable ozone molecules in natural conditions are formed and decomposed under the influence of various factors of animate and inanimate nature, and in the course of a long evolution this process has come to a certain dynamic equilibrium. The rate of ozone destruction reactions depends on catalysts, which can be both natural atmospheric oxides and substances released into the atmosphere as a result of natural disasters (for example, powerful volcanic eruptions).

However, in the second half of the last century, it was discovered that substances of industrial origin can also serve as catalysts for ozone destruction reactions, and humanity was seriously worried. Public opinion was especially excited by the discovery of the so-called ozone "hole" over Antarctica.

"Hole" over Antarctica

A noticeable decrease in the ozone layer over Antarctica - the ozone hole - was first discovered back in 1957, during the International Geophysical Year. Her real story began 28 years later with an article in the May issue of the magazine Nature, where it was suggested that the reason for the anomalous spring minimum of TO over Antarctica is industrial (including Freons) atmospheric pollution (Farman et al., 1985).

It was found that the ozone hole over Antarctica usually occurs once every two years, lasts about three months, and then disappears. It is not a through hole, as it may seem, but a recess, so it is more correct to speak of "ozone layer sagging". Unfortunately, all further studies of the ozone hole were mainly aimed at proving its anthropogenic origin (Roan, 1989).

Today, there are different hypotheses regarding the chemical and dynamic mechanisms of the formation of ozone holes. However, many known facts do not fit into the chemical anthropogenic theory. For example, the growth of stratospheric ozone in certain geographic regions.

Here is the most "naive" question: why is a hole formed in the southern hemisphere, although freons are produced in the northern, despite the fact that it is not known whether there is air communication between the hemispheres at that time?

None of the existing theories is based on large-scale detailed TO measurements and studies of processes occurring in the stratosphere. To answer the question about the degree of isolation of the polar stratosphere over Antarctica, as well as a number of other questions related to the problem of the formation of ozone holes, it was possible only with the help of a new method for tracking the movements of air flows proposed by V. B. Kashkin (Kashkin, Sukhinin, 2001; Kashkin et al., 2002).

Air flows in the troposphere (up to a height of 10 km) have long been traced by observing the translational and rotational movements of clouds. Ozone, in fact, is also a huge "cloud" over the entire surface of the Earth, and changes in its density can be used to judge the movement of air masses above 10 km, just as we know the direction of the wind by looking at a cloudy sky on an overcast day. For these purposes, the ozone density should be measured at the points of the spatial lattice with a certain time interval, for example, every 24 hours. By following how the ozone field has changed, it is possible to estimate the angle of its rotation per day, the direction and speed of movement.

Using the new method, the dynamics of the ozone layer was studied in 2000, when a record-breaking ozone hole was observed over Antarctica (Kashkin et al., 2002). For this, satellite data on the density of ozone throughout the southern hemisphere, from the equator to the pole, were used. As a result, it was found that the ozone content is minimal in the center of the funnel of the so-called circumpolar vortex, which formed above the pole, which we will discuss in detail below. On the basis of these data, a hypothesis of a natural mechanism for the formation of ozone "holes" was put forward.

Global dynamics of the stratosphere: a hypothesis

Circumpolar vortices are formed during the movement of stratospheric air masses in the meridional and latitudinal directions. How does this happen? The stratosphere is higher at the warm equator and lower at the cold pole. Air streams (together with ozone) roll down from the stratosphere like a hill, and move faster and faster from the equator to the pole. The movement from west to east occurs under the influence of the Coriolis force associated with the rotation of the Earth. As a result, air flows seem to be wound, like threads on a spindle, on the southern and northern hemispheres.

The "spindle" of air masses rotates throughout the year in both hemispheres, but is more pronounced in late winter and early spring, because the height of the stratosphere at the equator almost does not change throughout the year, and at the poles it is higher in summer and lower in winter, when it is especially Cold.

The ozone layer in the middle latitudes is created due to a powerful influx from the equator, as well as as a result of photochemical reactions occurring in place. But the ozone in the region of the pole owes its origin mainly to the flow from the equator and from the middle latitudes, and its content there is quite low. Photochemical reactions at the pole, where the sun's rays fall at a low angle, are slow, and a significant part of the ozone coming from the equator has time to be destroyed along the way.

But air masses don't always move like that. In the coldest winters, when the stratosphere over the pole drops very low above the Earth's surface and the "hill" becomes especially steep, the situation changes. Stratospheric currents roll down so fast that there is an effect familiar to anyone who has watched water flow down through a hole in a tub. Having reached a certain speed, the water begins to rotate rapidly, and a characteristic funnel is formed around the hole, created by centrifugal force.

Something similar happens in the global dynamics of stratospheric flows. When the currents of stratospheric air gain a sufficiently high speed, the centrifugal force begins to push them away from the pole towards the middle latitudes. As a result, air masses move from the equator and from the pole towards each other, which leads to the formation of a rapidly rotating "shaft" of the vortex in the middle latitudes.

The exchange of air between the equatorial and polar regions ceases, and ozone from the equator and from the middle latitudes does not reach the pole. In addition, the ozone remaining at the pole, as in a centrifuge, is squeezed out to the middle latitudes by centrifugal force, since it is heavier than air. As a result, the ozone concentration inside the funnel drops sharply - an ozone "hole" is formed above the pole, and in the middle latitudes - an area of ​​high ozone content, corresponding to the "shaft" of the circumpolar vortex.

In spring, the Antarctic stratosphere warms up and rises higher - the funnel disappears. Air communication between middle and high latitudes is being restored, and photochemical reactions of ozone formation are also accelerating. The ozone hole disappears before another particularly cold winter at the South Pole.

What about in the Arctic?

Although the dynamics of stratospheric flows and, accordingly, the ozone layer in the northern and southern hemispheres is generally similar, the ozone hole only occurs from time to time over the South Pole. There are no ozone holes above the North Pole because the winters are milder and the stratosphere never sinks low enough for air currents to pick up the speed needed to form a funnel.

There is another important difference. In the southern hemisphere, the circumpolar vortex rotates almost twice as fast as in the northern. And this is not surprising: Antarctica is surrounded by seas and there is a circumpolar sea current around it - in essence, gigantic masses of water and air rotate together. The picture is different in the northern hemisphere: in the middle latitudes there are continents with mountain ranges, and the friction of the air mass against the earth's surface does not allow the circumpolar vortex to gain a sufficiently high speed.

However, small ozone "holes" of a different origin sometimes appear in the middle latitudes of the northern hemisphere. Where do they come from? The movement of air in the mid-latitude stratosphere of the mountainous northern hemisphere resembles the movement of water in a shallow stream with a rocky bottom, when numerous whirlpools form on the surface of the water. In the middle latitudes of the northern hemisphere, the role of the bottom surface relief is played by temperature differences at the border of continents and oceans, mountain ranges and plains.

A sharp change in temperature on the Earth's surface leads to the formation of vertical flows in the troposphere. Stratospheric winds colliding with these currents create eddies that can rotate in both directions with equal probability. Within them, areas with low ozone content appear, that is, ozone holes much smaller in size than at the South Pole. And it should be noted that such vortices with different directions of rotation were discovered at the very first attempt.

Thus, the dynamics of stratospheric air currents, which we traced by observing the ozone cloud, allows us to give a plausible explanation for the mechanism of the formation of the ozone hole over Antarctica. Apparently, such changes in the ozone layer, due to aerodynamic phenomena in the stratosphere, took place long before the appearance of man.

All of the above does not mean at all that freons and other gases of industrial origin do not have a destructive effect on the ozone layer. However, scientists have yet to find out what is the ratio of natural and anthropogenic factors influencing the formation of ozone holes - it is unacceptable to draw hasty conclusions on such important issues.

Recently, newspapers and magazines are full of articles about the role of the ozone layer, in which people are intimidated by possible problems in the future. From scientists you can hear about the upcoming climate changes, which will negatively affect all life on Earth. Will a potential danger far from people really turn out to be such horrific events for all earthlings? What are the consequences of the destruction of the ozone layer for humanity?

The formation process and significance of the ozone layer

Ozone is a derivative of oxygen. While in the stratosphere, oxygen molecules are chemically attacked by ultraviolet radiation, after which they break up into free atoms, which, in turn, have the ability to combine with other molecules. With such an interaction of oxygen molecules and atoms with third bodies, a new substance is formed - this is how ozone is formed.

Being in the stratosphere, it affects the thermal regime of the Earth and the health of its population. As a planetary "guardian" ozone absorbs excess ultraviolet radiation. However, when it enters the lower atmosphere in large quantities, it becomes quite dangerous for the human species.

An unfortunate discovery of scientists - the ozone hole over Antarctica

The process of destruction of the ozone layer has been the subject of many discussions among scientists around the world since the late 1960s. In those years, environmentalists began to raise the problem of emissions of combustion products into the atmosphere in the form of water vapor and nitrogen oxides, which were produced by jet engines of rockets and airliners. There has been concern about the ozone-destroying property of nitric oxide emitted by aircraft at 25 km altitude, which is the formation area of ​​the earth's shield. In 1985, the British Antarctic Survey recorded a 40% decrease in atmospheric ozone over their base at Halley Bay.

After British scientists, this problem was covered by many other researchers. They managed to delineate an area with a low ozone content already outside the southern mainland. Because of this, the problem of the formation of ozone holes began to rise. Shortly thereafter, another ozone hole was discovered, now in the Arctic. However, it was smaller in size, with an ozone leakage of up to 9%.

According to the results of research, scientists have calculated that in 1979-1990 the concentration of this gas in the earth's atmosphere decreased by about 5%.

Destruction of the ozone layer: the appearance of ozone holes

The thickness of the ozone layer can be 3-4 mm, its maximum values ​​are at the poles, and the minimums are located along the equator. The largest concentration of gas can be found at 25 kilometers in the stratosphere over the Arctic. Dense layers sometimes occur at altitudes up to 70 km, usually in the tropics. The troposphere does not have a large amount of ozone, as it is more susceptible to seasonal changes and pollution of a different nature.

As soon as the gas concentration decreases by one percent, there is an increase in the intensity of ultraviolet light above the earth's surface by 2%. The influence of ultraviolet rays on planetary organics is compared with ionizing radiation.

The depletion of the ozone layer can cause catastrophes that will be associated with excessive heating, increased wind speeds and air circulation, which can lead to the emergence of new desert areas and reduce agricultural yields.

Encounter with ozone in everyday life

Sometimes after rain, especially in summer, the air becomes unusually fresh, pleasant, and people say that it “smells like ozone”. This is not figurative at all. In reality, some degree of ozone passes to the lower layers of the atmosphere with air mass flows. This type of gas is considered the so-called useful ozone, which brings a feeling of extraordinary freshness to the atmosphere. Basically, such phenomena are observed after thunderstorms.

However, there is also a very harmful, extremely dangerous variety of ozone for people. It is produced by exhaust gases and industrial emissions, and when exposed to the sun's rays, enters into a photochemical reaction. As a result, the so-called ground-level ozone is formed, which is extremely harmful to human health.

Substances that destroy the ozone layer: the action of freons

Scientists have proven that freons, which are massively charged with refrigerators and air conditioners, as well as numerous aerosol cans, cause the destruction of the ozone layer. Thus, it turns out that almost every person has a hand in the destruction of the ozone layer.

The causes of ozone holes are that freon molecules react with ozone molecules. Solar radiation forces freons to release chlorine. As a result, ozone splits, resulting in the formation of atomic and ordinary oxygen. In places where such interactions occur, the problem of ozone depletion occurs, and ozone holes occur.

Of course, industrial emissions bring the greatest harm to the ozone layer, but the domestic use of drugs that contain freon, one way or another, also has an impact on the destruction of ozone.

Ozone layer protection

After scientists documented that the ozone layer is still being destroyed, and ozone holes appear, politicians thought about its preservation. There have been consultations and meetings around the world on these issues. They were attended by representatives of all states with a well-developed industry.

So, in 1985, the Convention for the Protection of the Ozone Layer was adopted. This document was signed by representatives from forty-four states participating in the conference. A year later, another important document was signed, called the Montreal Protocol. In accordance with its provisions, there should have been a significant reduction in the world production and consumption of substances that lead to the violation of the ozone layer.

However, some states were unwilling to comply with such restrictions. Then, for each state, specific quotas for hazardous emissions into the atmosphere were determined.

Protection of the ozone layer in Russia

In accordance with the current Russian legislation, the legal protection of the ozone layer is one of the most important and priority areas. Legislation related to environmental protection regulates the list of protective measures aimed at protecting this natural object from various kinds of damage, pollution, destruction and depletion. Thus, Article 56 of the Legislation describes some activities related to the protection of the planet's ozone layer:

• Organizations for monitoring the effect of the ozone hole;
• Permanent control over climate change;
• Strict observance of the regulatory framework for harmful emissions into the atmosphere;
• Regulation of the production of chemical compounds that destroy the ozone layer;
• Application of penalties and penalties for violation of the law.

Possible solutions and first results

You should know that ozone holes are a fickle phenomenon. With the reduction of the amount of harmful emissions into the atmosphere, the gradual tightening of ozone holes begins - ozone molecules from neighboring areas are activated. However, in this case, another risk factor arises - neighboring areas are deprived of a significant amount of ozone, the layers become thinner.

Scientists around the world continue to research and intimidate with bleak conclusions. They calculated that if the presence of ozone decreased by only 1% in the upper atmosphere, then there would be an increase in skin cancers up to 3-6%. Moreover, a large amount of ultraviolet rays will adversely affect the immune system of people. They will become more vulnerable to a wide variety of infections.

It is possible that this can actually explain the fact that the number of malignant tumors is increasing in the 21st century. Increasing the level of ultraviolet radiation also negatively affects nature. There is a destruction of cells in plants, the process of mutation begins, as a result of which less oxygen is produced.

Will humanity cope with the upcoming challenges?

According to the latest statistical data, humanity is facing a global catastrophe. However, science also has optimistic reports. After the adoption of the Convention for the Protection of the Ozone Layer, all mankind has already taken up the problem of saving the ozone layer. Following the development of a number of prohibitive and precautionary measures, the situation was somewhat stabilized. Thus, some researchers argue that if all of humanity engages in industrial production within reasonable limits, the problem of ozone holes can be successfully solved.

If you have any questions - leave them in the comments below the article. We or our visitors will be happy to answer them.