home Health technologies Ozone holes are a modern problem. What is the ozone hole

Ozone holes are a modern problem. What is the ozone hole

IN Lately 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. You can hear from scientists about upcoming climate changes, which will negatively affect all life on Earth. Will a potential danger far removed from humans really turn into such horrific events for all earthlings? What consequences does humanity expect from the destruction of the ozone layer?

The formation process and significance of the ozone layer

Ozone is a derivative of oxygen. While in the stratosphere, oxygen molecules are chemically exposed to ultraviolet radiation, after which they break down into free atoms, which, in turn, have the ability to combine with other molecules. With this interaction of oxygen molecules and atoms with third bodies, a new substance arises - 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 by scientists - an ozone hole over Antarctica

The process of ozone layer depletion has been the subject of much debate among scientists around the world since the late 60s. 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. The concern has been that nitrogen oxide emitted by aircraft at 25 kilometers altitude, which is where the Earth's shield forms, can destroy ozone. In 1985, the British Antarctic Survey recorded a 40% decrease in the concentration of ozone in the atmosphere above their Hally Bay base.

After the British scientists, many other researchers illuminated this problem. They managed to delineate an area with low ozone levels already outside southern continent. Because of this, the problem of ozone hole formation began to arise. Soon after this, another ozone hole was discovered, this time in the Arctic. However, it was smaller in size, with ozone leakage up to 9%.

Based on the results of the research, scientists calculated that in 1979-1990 the concentration of this gas in the earth’s atmosphere decreased by about 5%.

Depletion of the ozone layer: the appearance of ozone holes

The thickness of the ozone layer can be 3-4mm, its maximum values are located at the poles, and its minimums are located along the equator. The highest concentration of gas can be found 25 kilometers in the stratosphere above the Arctic. Dense layers are sometimes found at altitudes up to 70 km, usually in the tropics. The troposphere does not contain much ozone because it is highly susceptible to seasonal changes and various types of pollution.

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

Depletion of the ozone layer could cause disasters associated with excessive heating, increased wind speeds and air circulation, which could lead to new desert areas and reduce agricultural yields.

Meeting ozone in everyday life

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

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

Substances that destroy the ozone layer: the effect of freons

Scientists have proven that freons, which are used en masse to charge 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 causes 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, the greatest harm to the ozone layer is caused by industrial emissions, but the household use of preparations that contain freon, one way or another, also has an impact on the destruction of ozone.

Protecting the ozone layer

After scientists documented that the ozone layer is still being destroyed and ozone holes appear, politicians began to think about preserving it. Consultations and meetings have been held around the world on these issues. Representatives of all states with well-developed industry took part in them.

Thus, in 1985, the Convention for the Protection of the Ozone Layer was adopted. Representatives from forty-four conference participating states signed this document. A year later, another important document called the Montreal Protocol was signed. In accordance with its provisions, there should have been a significant restriction of global production and consumption of substances that lead to ozone depletion.

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

Protection of the ozone layer in Russia

In accordance with current Russian legislation legal protection the ozone layer is one of the most important and priority areas. Legislation related to protection environment, a list of protective measures aimed at protecting this natural object from various types of damage, pollution, destruction and exhaustion. 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;
Continued control over climate change;
Strict compliance with the regulatory framework on harmful emissions into the atmosphere;
Regulating the production of chemical compounds that destroy the ozone layer;
Application of penalties and punishments for violation of the law.

Possible solutions and first results

You should know that ozone holes are not a permanent phenomenon. With a reduction in quantity harmful emissions A gradual tightening of ozone holes into the atmosphere begins - ozone molecules from neighboring areas are activated. However, at the same time, another risk factor arises - neighboring areas are deprived significant amount ozone, the layers become thinner.

Scientists around the world continue to engage in research and are intimidated by bleak conclusions. They calculated that if the presence of ozone decreased by just 1% in the upper atmosphere, there would be an increase in skin cancer of up to 3-6%. Moreover, a large number of ultraviolet rays will negatively affect people's immune system. They will become more vulnerable to a wide variety of infections.

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

Will humanity cope with the challenges ahead?

According to the latest statistics, 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 of humanity became involved in the problem of preserving the ozone layer. Following the development of a number of prohibitive and protective measures, the situation was slightly stabilized. Thus, some researchers argue that if all of humanity engages 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

Instructions

To prevent new ozone holes from forming, find out what causes them. Ozone is the same oxygen, but having not two atoms, but three. Oxygen acquires a third atom at an altitude of 12 - 50 kilometers due to the impact sun rays, due to which it is ionized. Ozone accumulates in upper layers atmosphere and forms the ozone layer, which covers the entire planet and protects it from the harmful effects of ultraviolet rays from the Sun.

Places where the ozone layer is noticeably thinner are called ozone holes. This layer has always become thinner, not only due to the harmful effects of human activity. The destruction of the ozone layer occurs due to chemical bond with hydrogen, bromine, methane, chlorine, etc. As a result, it forms completely different chemical compounds, but after some time this modification of oxygen accumulates again.

Plants, factories, transport, various Appliances increase the content in the atmosphere of substances that destroy the ozone layer, and its thinning occurs faster than restoration. The very first ozone hole appeared over Antarctica because the sun's rays needed to form ozone were insufficient there.

Now ozone holes have appeared over the Arctic, and the ozone layer in the atmosphere is decreasing. You can prevent new holes from forming by trying to use your car less. If the distance to your destination is short, walk. Do not spray without great need Air fresheners and all other sprays also contain substances that destroy the ozone layer.

If you have a summer house or a private house, plant more trees and other plants, they produce the necessary oxygen. Convince your friends and family to follow these too simple rules Only together will humanity contribute to the restoration of the ozone layer.

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What are ozone holes? How to prevent their occurrence?

Ozone is a bluish gas made up of three oxygen atoms (O3). When the ozone layer thins, more ultraviolet radiation begins to penetrate to the Earth, which is necessary for the normal functioning of people. Ozone absorbs excess ultraviolet radiation, including that which is dangerous for all life on Earth. Ozone holes are not a hole in the atmosphere in the full sense. This is a slow steady decrease in the concentration of the stratospheric layer.

Instructions

Loss has become more frequent lately extreme precipitation, and they, in turn, cause natural disasters(floods, landslides). It has not yet been established who is responsible for the ozone holes. Maybe the cause of their occurrence is flights, the result of human activity or greenhouse gases, but one thing is clear - the ozone layer is becoming thinner, and this is already a comprehensive problem.

However, the anthropogenic factor is only one component of the problem. There is a possibility that the planet itself is destroying itself, displacing humanity with the help of radiation ( – cancer diseases). The fact is that the map of ozone holes coincides with the map of methane deposits, which is why we can say that holes have always been. If you want to help, refuse aerosol packaging, be it deodorants, fresheners, etc. Do not release freon - monitor the integrity of the system in the refrigerator, car, etc.

Protest together with the “greens”, sign appeals to the governments of the world - the more activists, the greater the chance that you will be heard.

The General Assembly declared the International Day for the Preservation of the Ozone Layer in 1994. In 1987, Russia and 36 other countries signed a document obliging participating countries to limit or stop the production of ozone-depleting substances.

Large enterprises are monitored everywhere to see how they comply with air protection legislation. Countries have stopped the production of chlorofluorocarbons. Scientists believe that these measures taken (if humans are the culprit) will help renew the ozone layer by 2060, but until then, ozone layer depletion will greatly affect the climate.

In the upper part of the Earth's stratosphere, at an altitude of 20 to 50 km, there is a layer of ozone - triatomic oxygen. Under the influence of ultraviolet radiation, a molecule of ordinary oxygen (O2) attaches another atom, and as a result, an ozone molecule (O3) is formed.

Protective layer of the planet

Ozone layer depletion

In the 70s, during research, it was noticed that freon gas, used in air conditioners, refrigerators, etc., destroys ozone at a tremendous speed. Rising to the upper layers of the atmosphere, freons release chlorine, which decomposes ozone into ordinary and atomic oxygen. At the site of such interactions, an ozone hole is formed.

What does the ozone layer protect from?

Ozone holes are ubiquitous, but as many factors change, they are covered by ozone from neighboring layers of the atmosphere. Those, in turn, become even more subtle. The ozone layer acts as the only barrier to the destructive ultraviolet and radiation radiation of the sun. Without the ozone layer, the immune system would be destroyed.

Scientists estimate that a decrease in the ozone layer by just 1% increases the likelihood of cancer by 3-6%.

A decrease in the amount of ozone in the atmosphere will unpredictably change the climate on the planet. Because the ozone layer dissipates heat from the Earth's surface, as the ozone layer depletes the climate will become colder and the direction of some winds will change. All this will lead to natural disasters.

Montreal Protocol

In 1989, the majority of UN member states signed an agreement according to which the production of ozone-depleting freons and gases must be stopped. According to, after the signing of the agreement, the ozone layer should be fully restored by 2050.

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Sources:

What is the ozone layer for?

Ozone holes are areas in the Earth's ozone layer where the ozone gas, which protects the planet from radiation, is very low. Usually the process of their formation is associated with human activity, but there is an opinion that the origin of ozone holes is absolutely natural.

The ozone hole

It has been proven that freons released during the operation of many devices cause ozone loss in medium and high latitudes, but they do not affect the formation of polar ozone holes.

It is likely that a combination of many human and natural factors led to the formation of ozone holes. On the one hand, volcanic activity has increased, on the other, people have begun to seriously influence nature - the ozone layer can be damaged not only by the release of freon, but also by collisions with failed satellites. Thanks to a decrease in the number of erupting volcanoes since the end of the 20th century and restrictions on the use of freons, the situation has begun to improve slightly: scientists recently recorded a small hole over Antarctica. A more detailed study of ozone depletion will make it possible to prevent the emergence of these areas.

Tip 6: How to celebrate International Ozone Layer Day

On September 16, 1987, in the Canadian city of Montreal, delegates from 36 countries signed the Montreal Protocol. Each of these 36 states took upon itself the obligation to take all possible measures to gradually limit, and in the future, completely stop the production and use of substances that destroy the ozone layer of the earth's atmosphere.

In subsequent years, more and more states joined the protocol, including Russian Federation. The UN General Assembly in 1994 decided to declare September 16 as International Day for the Protection of the Ozone Layer.

This day was first celebrated in Russia in 2011. Employees of the Ministry of Natural Resources of the Russian Federation, the Global Environment Facility (GEF) and UN representatives took part in the program prepared and implemented on the basis of the State Polytechnic College No. 19 - the only educational institution Russia, training specialists in the field of installation and maintenance of industrial and domestic refrigeration equipment. The choice was not accidental, because the main source of destruction of the ozone layer is fluorinated refrigerants. And in order to control the reliability of refrigeration equipment, preventing leaks of refrigerants into the environment, as well as gradually reducing the volume of their production and use, qualified specialists in this field are needed.

On September 16 this year, Moscow will also celebrate Ozone Layer Protection Day. In addition to traditional reports and information on the results of observations of the thickness of the ozone layer in the polar regions, data on measures taken on regulating the circulation of ozone-depleting substances in Russia. There will be training computer games, dedicated to the topic of preserving the ozone layer. And in conclusion holiday a concert program will be shown.

Video on the topic

The first thing to be clear is that the ozone hole, contrary to its name, is not a hole in the atmosphere. The ozone molecule differs from an ordinary oxygen molecule in that it consists of not two, but three oxygen atoms connected to each other. In the atmosphere, ozone is concentrated in the so-called ozone layer, at an altitude of approximately 30 km within the stratosphere. This layer absorbs ultraviolet rays emitted by the Sun, otherwise solar radiation could cause great harm to life on the surface of the Earth. Therefore, any threat to the ozone layer deserves to be taken very seriously. In 1985, British scientists working on South Pole, found that during the Antarctic spring, atmospheric ozone levels there are significantly below normal. Every year at the same time, the amount of ozone decreased—sometimes to a greater extent, sometimes to a lesser extent. Similar, but less pronounced ozone holes also appeared over North Pole— during the Arctic spring.

In subsequent years, scientists figured out why the ozone hole appears. When the sun goes down and the long polar night begins, temperatures plummet and high stratospheric clouds containing ice crystals form. The appearance of these crystals causes a series of complex chemical reactions leading to the accumulation of molecular chlorine (a chlorine molecule consists of two joined chlorine atoms). When the sun appears and the Antarctic spring begins, under the influence of ultraviolet rays, intramolecular bonds are broken, and a stream of chlorine atoms rushes into the atmosphere. These atoms act as catalysts for reactions that convert ozone into simple oxygen, proceeding according to the following dual scheme:

Cl + O 3 -> ClO + O 2 and ClO + O -> Cl + O 2

As a result of these reactions, ozone molecules (O 3) are converted into oxygen molecules (O 2), with the original chlorine atoms remaining in a free state and again participating in this process (each chlorine molecule destroys a million ozone molecules before they are removed from the atmosphere under by other chemical reactions). As a result of this chain of transformations, ozone begins to disappear from the atmosphere over Antarctica, forming an ozone hole. However, soon, with warming, the Antarctic vortexes collapse, fresh air (containing new ozone) rushes into the area, and the hole disappears.

In 1987, the international Conference, dedicated to the threat to the ozone layer, and industrial the developed countries agreed to reduce and ultimately cease production chlorinated and fluorinated hydrocarbons (chlorofluorocarbons, CFCs) - chemicals that destroy the ozone layer. By 1992, the replacement of these substances with safe ones was so successful that a decision was made to completely destroy them by 1996. Today, scientists believe that in about fifty years the ozone layer will be completely restored.

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MINISTRY OF TRANSPORT OF THE RUSSIAN FEDERATION

FSOUVPO ULYANOVSK HIGHER AVIATION SCHOOL

CIVIL AVIATION (INSTITUTE)

FACULTY OF FLIGHT OPERATIONS AND AIR TRAFFIC MANAGEMENT

DEPARTMENT OF PASSOP

ABSTRACT

on the topic of:Ozone holes: causesAndconsequences

Completed by: Bazarov M.A.

Head: Morozova M.M.

Ulyanovsk 2012

Introduction

1. Reasons

2. Consequences

3. Geographical location

4. The role of the civil and military aviation in the formation of ozone holes

5. Ways to solve problems

Conclusion

Introduction

With the emergence of human civilization, a new factor appeared that influenced the fate of living nature. It has achieved enormous power in the current century and especially in recent times. 5 billion of our contemporaries have an impact on nature on the same scale as the people of the Stone Age could have had if their number had been 50 billion people, and the amount of energy released is received by the earth from the sun.

Since the emergence of a highly industrialized society, dangerous human intervention in nature has sharply increased, the scope of this intervention has expanded, it has become more diverse and now threatens to become a global danger to humanity.

The consumption of non-renewable raw materials is increasing, more and more arable land is leaving the economy, as cities and factories are built on it. The Earth's biosphere is currently subject to increasing anthropogenic impact. At the same time, several of the most significant processes can be identified, any of which does not improve the condition of the airspace of our planet.

The accumulation of carbon dioxide in the atmosphere is also progressing. The further development of this process will strengthen the undesirable trend towards an increase in the average annual temperature on the planet.

As a result, society faced a dilemma: either mindlessly roll towards its inevitable death in the impending environmental disaster, or consciously transform the powerful forces of science and technology created by the genius of man from a weapon previously turned against nature and man himself, into a weapon for their protection and prosperity, into a tool for rational use of natural resources.

A real threat of a global environmental crisis looms over the world, understood by the entire population of the planet, and the real hope for its prevention lies in continuous environmental education and enlightenment of people.

The World Health Organization has determined that human health depends 20% on heredity, 20% on the environment, 50% on lifestyle and 10% on medicine. In a number of regions of Russia, by 2005, the following dynamics of factors influencing human health are expected: the role of ecology will increase to 40%, the effect of the genetic factor will increase to 30%, the ability to maintain health through lifestyle will decrease to 25%, and the role of medicine will decrease to 5%. .

Characterizing the current state of ecology as critical, we can identify the main reasons that lead to environmental disaster: pollution, poisoning of the environment, depletion of the atmosphere in oxygen, ozone holes.

The purpose of this work was to summarize the literature data on the causes and consequences of the destruction of the ozone layer, as well as ways to solve the problem of the formation of “ozone holes”.

ozone layer hole environmental

1. Causes

Ozone hole is a local drop in ozone concentration in the Earth's ozone layer. According to the theory generally accepted in the scientific community, in the second half of the 20th century, the increasing impact of the anthropogenic factor in the form of the release of chlorine- and bromine-containing freons led to a significant thinning of the ozone layer.

According to another hypothesis, the process of formation of “ozone holes” may be largely natural and not associated solely with the harmful effects of human civilization.

An ozone hole with a diameter of over 1000 km was first discovered in 1985, on Southern Hemisphere, over Antarctica, a group of British scientists: J. Shanklin (English), J. Farman (English), B. Gardiner (English), who published a corresponding article in the journal Nature. Every August it appeared, and in December - January it ceased to exist. Another hole was forming over the Northern Hemisphere in the Arctic, but of a smaller size. At this stage of human development, world scientists have proven that there are a huge number of ozone holes on Earth. But the most dangerous and largest is located above Antarctica.

A combination of factors leads to a decrease in ozone concentration in the atmosphere, the main of which is the death of ozone molecules in reactions with various substances of anthropogenic and natural origin, the absence of solar radiation during the polar winter, a particularly stable polar vortex that prevents the penetration of ozone from subpolar latitudes, and the formation polar stratospheric clouds (PSC), the surface of which particles catalyze ozone decay reactions. These factors are especially characteristic of the Antarctic; in the Arctic, the polar vortex is much weaker due to the absence of a continental surface, the temperature is several degrees higher than in the Antarctic, and PSOs are less common and also tend to disintegrate in early autumn. Being chemically active, ozone molecules can react with many inorganic and organic compounds. The main substances that contribute to the destruction of ozone molecules are simple substances (hydrogen, oxygen, chlorine, bromine atoms), inorganic (hydrogen chloride, nitrogen monoxide) and organic compounds (methane, fluorochlorine and fluorobromofreons, which release chlorine and bromine atoms). In contrast, for example, to hydrofluorofreons, which decompose to fluorine atoms, which, in turn, quickly react with water to form stable hydrogen fluoride. Thus, fluorine does not participate in ozone decomposition reactions. Iodine also does not destroy stratospheric ozone, since iodine-containing organic substances are almost completely consumed in the troposphere. The main reactions that contribute to the destruction of ozone are given in the article about the ozone layer.

Chlorine “eats” both ozone and atomic oxygen due to fairly rapid reactions:

O3 + Cl = O2 + ClO

СlO + O = Cl + O2

Moreover, the latter reaction leads to the regeneration of active chlorine. Chlorine, thus, is not even consumed, destroying the ozone layer.

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:

the influence of particles emitted during atomic explosions;

flights of rockets and high-altitude aircraft;

reactions with ozone of certain substances produced by chemical plants. These are primarily chlorinated hydrocarbons and especially freons - chlorofluorocarbons, or hydrocarbons in which all or most of the 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 of sunlight, they decompose, releasing atomic chlorine, which serves as the main “disturber of order” in the ozone layer.

2. Consequences

The ozone hole poses a danger to living organisms because the ozone layer protects the Earth's surface from excessive doses of ultraviolet radiation from the Sun. The weakening of the ozone layer increases the flow of solar radiation onto the earth and causes an increase in the number of skin cancers in people. Plants and animals also suffer from increased levels of radiation.

Ozone in the stratosphere protects the Earth from destructive ultraviolet and solar radiation. Depleting the ozone layer will allow more solar radiation to reach the Earth's surface.

Each percent of stratospheric ozone lost results in a 1.5 to 2 percent increase in exposure to ultraviolet solar radiation, according to the U.S. Environmental Protection Agency. For humans, an increase in the intensity of ultraviolet radiation is primarily dangerous due to the effects of solar radiation on the skin and eyes.

Radiation with wavelengths in the spectrum from 280 to 320 nanometers - UV rays, which are partially blocked by ozone - can cause premature aging and an increase in the number of skin cancers, as well as damage to plants and animals.

Radiation with a wavelength greater than 320 nanometers, the UV spectrum, is practically not absorbed by ozone and is actually necessary for humans to form vitamin D. UV radiation with a wavelength in the spectrum of 200 - 280 nanometers can cause serious consequences for biological organisms. However, radiation from this spectrum is almost completely absorbed by ozone. Thus, the “Achilles heel” of earthly life is the radiation of a rather narrow spectrum of UV waves with a length from 320 to 280 nanometers. As wavelengths shorten, their ability to harm living organisms and DNA increases. Fortunately, ozone's ability to absorb ultraviolet radiation increases as the wavelength of the radiation decreases.

· Increasing incidence of skin cancer.

· Suppression immune system person.

· Eye damage.

Ultraviolet radiation can damage the cornea, connective tissue of the eye, lens and retina. Ultraviolet radiation can cause photokeratosis (or snow blindness), similar to a sunburn of the cornea or connective tissue of the eye. Increased exposure to ultraviolet radiation as a result of ozone depletion will lead to an increase in the number of people with cataracts, according to the authors of How to Save Our Skin. Cataracts cover the lens of the eye, reducing visual acuity and can cause blindness.

· Destruction of crops.

3. Geographical location

The thinning of the ozone layer began to be recorded in the 70s. It decreased especially significantly over Antarctica, which led to the emergence of the common expression “ozone hole.” Small holes are also recorded in the northern hemisphere - over the Arctic, in the area of the Plesetsk and Baikonur cosmodromes. In 1974, two scientists from the University of California - Mario Molina and Sherward Rowland - hypothesized that the main factor in ozone destruction was freon gases used in the refrigeration and perfume industries. Less significant ozone depleting factors are the flights of rockets and supersonic aircraft.

The location of the “ozone holes” tends to localize positive global magnetic anomalies. In the Southern Hemisphere this is the Antarctic, and in the Northern Hemisphere it is the East Siberian global magnetic anomaly. Moreover, the power of the Siberian anomaly is growing so strongly that even in Novosibirsk the vertical component of the geomagnetic field is growing annually by 30 gamma (nanotesla).

The loss of the ozone layer over the Arctic basin was so significant this year that for the first time in the history of observations we can talk about the emergence of an “ozone hole” similar to the Antarctic one. At altitudes above 20 km, ozone loss was about 80%. The probable reason for this phenomenon is the unusually long preservation of relatively low temperatures in the stratosphere at these latitudes.

4. The role of civil and military aviation in educationozone holes

The destruction of the ozone layer is facilitated not only by freons released into the atmosphere and entering the stratosphere. Nitrogen oxides, which are formed during nuclear explosions. But nitrogen oxides are also formed in the combustion chambers of turbojet engines of high-altitude aircraft. Nitrogen oxides are formed from the nitrogen and oxygen that are found there. The higher the temperature, i.e., the greater the engine power, the greater the rate of formation of nitrogen oxides.

It's not just the power of an airplane's engine that matters, but also the altitude at which it flies and releases ozone-depleting nitrogen oxides. The higher the nitrous oxide or oxide is formed, the more destructive it is to ozone.

The total amount of nitrogen oxide that is emitted into the atmosphere per year is estimated at 1 billion tons. About a third of this amount is emitted by aircraft above the average tropopause level (11 km). As for aircraft, the most harmful emissions are from military aircraft, the number of which amounts to tens of thousands. They fly primarily at altitudes in the ozone layer.

5. Ways to solve problems

To begin global restoration, 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.

Also, we - all people - must understand this and help nature start the process of restoring the ozone layer, new forest plantings are needed, stop cutting down forests for other countries that for some reason do not want to cut down theirs, but make money from our forests.

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. The laser beams will be directed towards central part ozone layer and will constantly feed it. The energy source can be solar panels. Astronauts on these platforms will only be required for periodic inspections and repairs.

Conclusion

The potential for human impact on nature is constantly growing and has already reached a level where it is possible to cause irreparable damage to the biosphere. This is not the first time a substance that for a long time It was considered completely harmless, but turns out to be extremely dangerous. Twenty years ago, hardly anyone could have imagined that an ordinary aerosol can could pose a serious threat to the planet as a whole. Unfortunately, it is not always possible to predict in time how this or that compound will affect the biosphere. However, in the case of CFCs there was such a possibility: all the chemical reactions that describe the process of destruction of ozone by CFCs are extremely simple and have been known for quite a long time. But even after the CFC problem was formulated in 1974, the only country that took any measures to reduce CFC production was the United States, and these measures were completely insufficient. It took a strong enough demonstration of the dangers of CFCs for serious action to be taken on a global scale. It should be noted that even after the discovery of the ozone hole, ratification of the Montreal Convention was at one time in jeopardy. Perhaps the CFC problem will teach us to treat with greater attention and caution all substances entering the biosphere as a result of human activity.

The problem of historical and modern climate change has turned out to be very complex and does not find a solution in the schemes of single-factor determinism. Along with the increase in carbon dioxide concentration, changes in the ozonosphere associated with the evolution of the geomagnetic field play an important role. The development and testing of new hypotheses are a necessary condition for understanding the patterns of general atmospheric circulation and other geophysical processes affecting the biosphere.

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Introduction.

In the 21st century Among the many global environmental problems of the biosphere, the problem of destruction of the ozone layer and the associated increase in biologically hazardous ultraviolet radiation in the biosphere remains very relevant. earth's surface. This could further develop into an irreversible catastrophe destructive for humanity. In recent decades, numerous studies have established a steady trend towards a decrease in the ozone content in the atmosphere. According to the World Health Organization (WHO), every 1% decrease in ozone levels in the atmosphere (and corresponding 2% increase in UV radiation) leads to a 5% increase in the number of cancer diseases.

The modern oxygen atmosphere of the Earth is a unique phenomenon among the planets of the solar system, and this feature is associated with the presence of life on our planet.

The environmental problem is undoubtedly the most important for people now. The reality of an environmental catastrophe is indicated by the destruction of the Earth's ozone layer. Ozone is a triatomic form of oxygen, formed in the upper layers of the atmosphere under the influence of hard (short-wave) ultraviolet radiation from the Sun.

Today, ozone worries everyone, even those who previously did not suspect the existence of an ozone layer in the atmosphere, but only believed that the smell of ozone was a sign of fresh air. (It’s not for nothing that ozone means “smell” in Greek.) This interest is understandable - we are talking about the future of the entire biosphere of the Earth, including man himself. Currently, there is a need to make certain decisions that are binding on everyone, which would allow us to preserve the ozone layer. But for these decisions to be correct, it is necessary full information about those factors that change the amount of ozone in the Earth’s atmosphere, as well as about the properties of ozone, and how exactly it reacts to these factors. Therefore, I consider the topic I have chosen to be relevant and necessary for consideration.

Main part: Ozone determination

It is known that ozone (Oz), a modification of oxygen, has high chemical reactivity and toxicity. Ozone is formed in the atmosphere from oxygen during electrical discharges during thunderstorms and under the influence of ultraviolet radiation from the Sun in the stratosphere. The ozone layer (ozone screen, ozonosphere) is located in the atmosphere at an altitude of 10-15 km with a maximum ozone concentration at an altitude of 20-25 km. The ozone screen delays the penetration of the most severe UV radiation (wavelength 200-320 nm), which is destructive for all living things, to the earth's surface. However, as a result of anthropogenic impacts, the ozone “umbrella” became leaky and ozone holes began to appear in it with a noticeably reduced (up to 50% or more) ozone content.

Causes of ozone holes

Ozone (ozone) holes are only part of a complex environmental problem depletion of the Earth's ozone layer. In the early 1980s. a decrease in the total ozone content in the atmosphere was noted over the area of scientific stations in Antarctica. So, in October 1985 There were reports that the ozone concentration in the stratosphere over the English station Halley Bay decreased by 40% from its minimum values, and over the Japanese station - almost 2 times. This phenomenon is what caused the “ozone hole.” Significant ozone holes appeared over Antarctica in the spring of 1987, 1992, 1997, when a decrease in the total content of stratospheric ozone (TO) by 40 - 60% was recorded. In the spring of 1998, the ozone hole over Antarctica reached a record area of 26 million square meters. km (3 times the territory of Australia). And at an altitude of 14 - 25 km in the atmosphere, almost complete destruction of ozone occurred.

Similar phenomena were observed in the Arctic (especially since the spring of 1986), but the size of the ozone hole here was almost 2 times smaller than over the Antarctic. In March 1995 The Arctic ozone layer was depleted by about 50%, and “mini-holes” formed over the northern regions of Canada and the Scandinavian Peninsula, the Scottish Islands (UK).

Currently, there are about 120 ozonometric stations in the world, including 40 that have appeared since the 60s. XX century on Russian territory. Observational data from ground stations indicate that in 1997, a calm state of total ozone content was observed over almost the entire controlled territory of Russia.

To clarify the reasons for the emergence of powerful ozone holes precisely in the circumpolar spaces at the end of the twentieth century. Research was carried out (using flying laboratory aircraft) of the ozone layer over Antarctica and the Arctic. It has been established that, in addition to anthropogenic factors (emissions of freons, nitrogen oxides, methyl bromide, etc. into the atmosphere), natural influences play a significant role. Thus, in the spring of 1997, in some areas of the Arctic, a drop in ozone content in the atmosphere of up to 60% was recorded. Moreover, over the course of a number of years, the rate of depletion of the ozonosphere over the Arctic has been increasing even in conditions when the concentration of chlorofluorocarbons (CFCs), or freons, in it remained constant. According to a Norwegian scientist K. Henriksen, during last decade In the lower layers of the Arctic stratosphere, an ever-expanding funnel of cold air was formed. It created ideal conditions for the destruction of ozone molecules, which occurs mainly at a very low temperature (about -80*C). A similar funnel over Antarctica is the cause of ozone holes. Thus, the cause of the ozone depletion process in high latitudes (Arctic, Antarctica) may be largely due to natural influences.

Diagnostics and diseases. Medicines from A to Z

Ozone holes are a modern problem. What is the ozone hole

The formation process and significance of the ozone layer

An unfortunate discovery by scientists - an ozone hole over Antarctica

Depletion of the ozone layer: the appearance of ozone holes

Meeting ozone in everyday life

Substances that destroy the ozone layer: the effect of freons

Protecting the ozone layer

Protection of the ozone layer in Russia

Possible solutions and first results

Will humanity cope with the challenges ahead?

Protective layer of the planet

Ozone layer depletion

What does the ozone layer protect from?

Montreal Protocol

The ozone hole

Tip 6: How to celebrate International Ozone Layer Day

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Introduction.

Main part: Ozone determination

Causes of ozone holes