In the last decade, the phrase "greenhouse effect" has practically never left the television screens or from the pages of newspapers. Curricula in several disciplines at once provide for its thorough study, and its negative significance for the climate of our planet is almost always indicated. However, this phenomenon is actually much more multifaceted than it is presented to the layman.

Without the greenhouse effect, life on our planet would be in question

You can start with the fact that the greenhouse effect on our planet has existed throughout its history. Such a phenomenon is simply inevitable for those celestial bodies that, like the Earth, have a stable atmosphere. Without it, for example, the World Ocean would have frozen long ago, and the higher forms of life would not have appeared at all. Scientists have long scientifically proven that if there were no carbon dioxide in our atmosphere, the presence of which is a necessary factor in the process of the greenhouse effect, then the temperature on the planet would fluctuate within -20 0 C, so there would be no talk of the emergence of life at all.

Causes and essence of the greenhouse effect

Answering the question: "What is the greenhouse effect?", First of all, it should be noted that this physical phenomenon got its name by analogy with the processes that occur in the gardeners' greenhouse. Inside it, regardless of the season, it is always a few degrees warmer than in the surrounding space. The thing is that plants absorb visible sunlight, which pass absolutely freely through glass, and through polyethylene, and in general through almost any obstacle. After that, the plants themselves also begin to radiate energy, but already in the infrared range, the rays of which can no longer freely overcome the same glass, so a greenhouse effect occurs. The reasons for this phenomenon, therefore, lie precisely in the imbalance between the spectrum of visible sunlight and those radiations that plants and other objects emit into the external environment.

The physical basis of the greenhouse effect

As for our planet as a whole, the greenhouse effect here arises due to the presence of a stable atmosphere. To maintain its temperature balance, the Earth must give off as much energy as it receives from the Sun. However, the presence of carbon dioxide and water in the atmosphere, which absorb infrared rays, thus acting as glass in a greenhouse, causes the formation of so-called greenhouse gases, some of which returns back to the Earth. These gases create a "quilt effect", raising the temperature near the surface of the planet.

Greenhouse effect on Venus

From the foregoing, we can conclude that the greenhouse effect is characteristic not only for the Earth, but also for all planets and other celestial bodies with a stable atmosphere. Indeed, studies conducted by scientists have shown that, for example, on the surface of Venus, this phenomenon is much more pronounced, which is primarily due to the fact that its air envelope is almost one hundred percent carbon dioxide.

Greenhouse effect - the process of increasing the temperature near the earth's surface due to an increase in the concentration of greenhouse gases (Figure 3).

Greenhouse gases- these are gaseous compounds that intensively absorb infrared rays (thermal rays) and contribute to the heating of the surface layer of the atmosphere; these include: primarily CO 2 (carbon dioxide), but also methane, chlorofluorocarbons (CFCs), nitrogen oxides, ozone, water vapour.

These impurities prevent long-wave thermal radiation from the earth's surface. Part of this absorbed thermal radiation returns back to the earth's surface. Consequently, with an increase in the concentration of greenhouse gases in the surface layer of the atmosphere, the intensity of absorption of infrared radiation emanating from the earth's surface also increases, which means that the air temperature increases (climate warming).

An important function of greenhouse gases is to maintain a relatively constant and moderate temperature on the surface of our planet. Carbon dioxide and water are mainly responsible for maintaining favorable temperature conditions near the Earth's surface.

Figure 3. Greenhouse effect

The earth is in thermal equilibrium with its surroundings. This means that the planet radiates energy into outer space at a rate equal to the absorption rate of solar energy. Since the Earth is a relatively cold body with a temperature of 254 K, the radiation of such cold bodies falls on the long-wave (low-energy) part of the spectrum, i.e. The maximum intensity of the Earth's radiation is located near the wavelength of 12,000 nm.

Most of this radiation is retained by CO 2 and H 2 O, which also absorb it in the infrared region, thus these components do not allow heat to dissipate and maintain a uniform temperature suitable for life near the Earth's surface. Water vapor plays an important role in maintaining the temperature of the atmosphere at night, when the earth's surface radiates energy into outer space and does not receive solar energy. In deserts with a very arid climate, where the concentration of water vapor is very low, it is unbearably hot during the day, but very cold at night.

The main reasons for the increase in the greenhouse effect– a significant release of greenhouse gases into the atmosphere and an increase in their concentrations; what is happening in connection with the intensive burning of fossil fuels (coal, natural gas, oil products), the reduction of vegetation: deforestation; drying up of forests due to pollution, burning of vegetation during fires, etc. As a result, the natural balance between the consumption of CO 2 by plants and its intake in the process of respiration (physiological, decay, combustion) is disturbed.

According to scientists, with a probability of more than 90%, it is human activity in burning natural fuels and the greenhouse effect caused by this that largely explains global warming in the last 50 years. The processes caused by human activity are like a train that has lost control. It is almost impossible to stop them, warming will continue for at least several centuries, or even a whole millennium. As environmentalists have established, so far the world's oceans have absorbed the lion's share of heat, but the capacity of this giant battery is running out - the water has warmed up to a depth of three kilometers. The result is global climate change.

Concentration of the main greenhouse gas(CO 2) in the atmosphere at the beginning of the 20th century was » 0.029%, by now it has reached 0.038%, i.e. increased by almost 30%. If current impacts on the biosphere are allowed to continue, by 2050, the concentration of CO 2 in the atmosphere will double. In this connection, they predict an increase in temperature on Earth by 1.5 ° C - 4.5 ° C (up to 10 ° C in the polar regions, 1 ° C -2 ° C in the equatorial regions).

This, in turn, can lead to a critical increase in the temperature of the atmosphere in arid zones, which will lead to the death of living organisms, a decrease in their vital activity; desertification of new territories; melting of polar and mountain glaciers, which means a rise in the level of the world ocean by 1.5 m, flooding of coastal zones, increased storm activity, and migration of the population.

Consequences of global warming:

1. As a result of global warming, change in atmospheric circulation , change in the distribution of precipitation, change in the structure of biocenoses; in a number of regions, a decrease in the yield of agricultural crops.

2. global climate change . Australia suffer more. Climatologists predict a climate catastrophe for Sydney: by 2070, the average temperature in this Australian metropolis will rise by about five degrees, forest fires will devastate its surroundings, and giant waves will destroy sea beaches. Europe will devastate climate change. The ecosystem will be destabilized by relentlessly rising temperatures, EU scientists predict in a report. In the north of the continent, crop yields will increase with an increase in the length of the growing season and the frost-free period. The already warm and arid climate of this part of the planet will become even warmer, leading to droughts and the drying up of many fresh water reservoirs (Southern Europe). These changes will be a real challenge for farmers and foresters. In Northern Europe, warm winters will be accompanied by increased precipitation. Warming in the north of the region will also lead to positive phenomena: the expansion of forests and the growth of crops. However, they will go hand in hand with floods, destruction of coastal areas, the disappearance of some species of animals and plants, melting of glaciers and permafrost regions. AT Far East and Siberian regions the number of cold days will decrease by 10-15, and in the European part - by 15-30.

3. Global climate change is already costing humanity 315 thousand lives annually, and this figure is constantly increasing every year. It causes disease, drought and other weather anomalies that are already killing people. The organization's experts also cite other data - according to their estimates, more than 325 million people, usually from developing countries, are currently affected by climate change. Experts estimate the impact of global warming on the world economy at $125 billion in damage annually, and by 2030 this amount could rise to $340 billion.

4. Survey 30 glaciers in various regions of the globe, conducted by the World Glacier Watch, showed that in 2005 the thickness of the ice cover decreased by 60-70 centimeters. This figure is 1.6 times the annual average of the 1990s and 3 times the average of the 1980s. According to some experts, despite the fact that the thickness of the glaciers is only a few tens of meters, if their melting continues at such a pace, in a few decades the glaciers will disappear altogether. The most dramatic processes of glacier melting have been noted in Europe. Thus, the Norwegian glacier Breydalblikkbrea (Breidalblikkbrea) in 2006 lost more than three meters, which is 10 times more than in 2005. Threatening melting of glaciers has been noted in Austria, Switzerland, Sweden, France, Italy and Spain. In the zone of the Himalayan mountains. The current trend of glacier melt suggests that rivers such as the Ganges, Indus, Brahmaputra (the highest river in the world) and other rivers crossing the northern plain of India may become seasonal rivers in the near future due to climate change.

5. Rapid melting permafrost Due to climate warming, today it poses a serious threat to Russia's northern regions, half of which are located in the so-called "permafrost zone". Experts from the Ministry of Emergency Situations of the Russian Federation give forecasts: according to their calculations, the area of ​​permafrost in Russia will decrease by more than 20% over the next 30 years, and the depth of soil thawing will decrease by 50%. The greatest changes in climate may occur in the Arkhangelsk region, the Komi Republic, the Khanty-Mansi Autonomous Okrug and Yakutia. Experts predict that the thawing of permafrost will lead to significant changes in the landscape, high-flowing rivers, and the formation of thermokarst lakes. In addition, due to the melting of permafrost, the rate of erosion of the Russian Arctic coasts will increase. Paradoxically, due to changes in the coastal landscape, the territory of Russia may be reduced by several tens of square kilometers. Due to climate warming, other northern countries are also suffering from coastline erosion. So, for example, the process of wave erosion will lead [http://ecoportal.su/news.php?id=56170] to the complete disappearance of the northernmost island of Iceland by 2020. The island of Kolbinsi (Kolbeinsey), which is considered the northernmost point of Iceland, will completely disappear under water by 2020 as a result of accelerating the process of abrasion - wave erosion of the coast.

6. World ocean level by 2100 could rise by 59 centimeters, according to a report by a UN expert group. But this is not the limit, if the ice of Greenland and Antarctica melts, then the level of the World Ocean can rise even higher. Only the top of the dome of St. Isaac's Cathedral and the spire of the Peter and Paul Fortress, sticking out of the water, will then indicate the location of St. Petersburg. A similar fate will befall London, Stockholm, Copenhagen and other major seaside cities.

7. Tim Lenton, a climate expert at the University of East Anglia and colleagues, using the mathematical calculations made, found that an increase in the average annual temperature by even 2 ° C over 100 years will cause 20-40% death Amazonian forests due to the impending drought. A 3°C rise in temperature will cause the death of 75% of the forests within 100 years, and a 4°C rise in temperature will cause the disappearance of 85% of all Amazon forests. And they absorb CO 2 most efficiently (Photo: NASA, presentation).

8. At the current rate of global warming, by 2080 up to 3.2 billion people on the globe will face the problem lack of drinking water . Scientists note that water difficulties will primarily affect Africa and the Middle East, but a critical situation may also develop in China, Australia, parts of Europe and the United States. The UN has published a list of countries that will be most affected by climate change. It is led by India, Pakistan and Afghanistan.

9. climate migrants . Global warming will lead to the fact that by the end of the 21st century, one more category of refugees and migrants may be added - climate. By 2100, the number of climate migrants could reach about 200 million people.

The fact that warming exists, none of the scientists doubt - it's obvious. But there are alternative points of view. For example, Corresponding Member of the Russian Academy of Sciences, Doctor of Geography, Professor, Head of the Department of Environmental Management of Moscow State University Andrey Kapitsa considers climate change to be a normal natural phenomenon. There is global warming, it alternates with global cooling.

Supporters "classical" approach to the problem of the greenhouse effect come from the assumption of the Swedish scientist Svante Arrhenius about the warming of the atmosphere as a result of the fact that "greenhouse gases" freely pass the sun's rays to the Earth's surface and at the same time delay the radiation of the earth's heat into space. However, the processes of heat transfer in the Earth's atmosphere turned out to be much more complicated. The gas "layer" regulates the flow of solar heat differently than the glass of a backyard greenhouse.

In fact, gases such as carbon dioxide do not cause the greenhouse effect. This has been convincingly proven by Russian scientists. Academician Oleg Sorokhtin, who works at the Institute of Oceanology of the Russian Academy of Sciences, was the first to create a mathematical theory of the greenhouse effect. From his calculations, confirmed by measurements on Mars and Venus, it follows that even significant emissions of technogenic carbon dioxide into the Earth's atmosphere practically do not change the thermal regime of the Earth and do not create a greenhouse effect. On the contrary, we should expect a slight, fraction of a degree, cooling.

It was not the increased content of CO2 in the atmosphere that led to warming, but As a result of warming, gigantic volumes of carbon dioxide were released into the atmosphere - notice, without any human participation. 95 percent of CO 2 is dissolved in the world's oceans. It is enough for the water column to warm up by half a degree - and the ocean will "exhale" carbon dioxide. Volcanic eruptions and forest fires also make a significant contribution to the pumping of the earth's atmosphere with CO 2 . With all the costs of industrial progress, the emission of greenhouse gases from the pipes of factories and thermal power plants does not exceed a few percent of the total turnover of carbon dioxide in nature.

There are known ice ages that alternated with global warming, and now we are in a period of global warming. Normal climate fluctuations, which are associated with fluctuations in the activity of the Sun and the Earth's orbit. Not with human activity at all.

We managed to look 800 thousand years ago into the past of the Earth thanks to a well drilled in the thickness of a glacier in Antarctica (3800 m).

From the air bubbles preserved in the core, the temperature, age, carbon dioxide content were determined and curves were obtained for about 800 thousand years. According to the ratio of oxygen isotopes in these bubbles, scientists determined the temperature at which snow fell. The data obtained cover most of the Quaternary period. Of course, in the distant past, man could not influence nature. But it was found that the content of CO 2 then changed very much. Moreover, each time it was warming that preceded the increase in the concentration of CO 2 in the air. The theory of the greenhouse effect assumes the reverse sequence.

There are certain ice ages that alternated with periods of warming. Now we are just in a period of warming, and it has been going on since the Little Ice Age, which was in the 15th - 16th centuries, since the 16th century, there has been about one degree of warming per century.

But what is called the "greenhouse effect" - this phenomenon is not a proven fact. Physicists show that CO 2 does not contribute to the greenhouse effect.

In 1998, Frederick Seitz, former president of the US National Academy of Sciences, submitted a petition to the scientific community calling on US and other governments to reject the Kyoto agreements to limit greenhouse gas emissions. The petition was accompanied by an overview, from which it follows that over the past 300 years, warming has been observed on Earth. And the impact of human activity on climate change has not been reliably established. In addition, Seitz argues that increased CO2 stimulates photosynthesis in plants and thus contributes to increased agricultural productivity, accelerated forest growth. The petition was signed by 16,000 scientists. However, the Clinton administration shrugged off these appeals, signaling that the debate about the nature of global climate change was over.

In fact, cosmic factors lead to serious climate changes. The temperature is changed by fluctuations in solar activity, as well as changes in the inclination of the earth's axis, the period of revolution of our planet. Such fluctuations in the past, as is known, led to the onset of ice ages.

Global warming is a political issue. And here there is a struggle of two directions. One direction is those who use fuel, oil, gas, coal. They prove in every possible way that the harm is caused by the transition to nuclear fuel. And supporters of nuclear fuel prove the opposite, that it is just the opposite - gas, oil, coal give CO 2 and cause warming. This is a struggle between two major economic systems.

Publications on this subject are full of gloomy prophecies. I do not agree with such assessments. An increase in the average annual temperature within one degree per century will not lead to fatal consequences. It takes a huge amount of energy to melt the ice of Antarctica, the boundaries of which have practically not narrowed over the entire period of observations. At least in the 21st century, climate cataclysms do not threaten humanity.

If you do not stop its growth, the balance on Earth may be disturbed. The climate will change, famine and disease will come. Scientists are developing various measures to combat the problem, which should become global.

essence

What is the greenhouse effect? This is the name given to the increase in surface temperature of the planet due to the fact that gases in the atmosphere tend to retain heat. The earth is heated by radiation from the sun. Visible short waves from a light source freely penetrate to the surface of our planet. As it warms up, the Earth begins to radiate long heat waves. Partially, they penetrate through the layers of the atmosphere and “leave” into space. reduce bandwidth, reflect long waves. Heat remains at the surface of the Earth. The higher the concentration of gases, the higher the greenhouse effect.

The phenomenon was first described by Joseph Fourier at the beginning of the 19th century. He suggested that the processes occurring in the earth's atmosphere are similar to what exists under glass.

Greenhouse gases are steam (from water), carbon dioxide (carbon dioxide), methane, ozone. The former takes the main part in the formation of the greenhouse effect (up to 72%). The next most important is carbon dioxide (9-26%), the share of methane and ozone is 4-9 and 3-7%, respectively.

Recently, you can often hear about the greenhouse effect as a serious environmental problem. But this phenomenon also has a positive side. Due to the fact that the greenhouse effect exists, the average temperature of our planet is about 15 degrees above zero. Without it, life on Earth would not be possible. The temperature could only be minus 18.

The reason for the appearance of the effect is the active activity of many volcanoes on the planet millions of years ago. At the same time, the content of water vapor and carbon dioxide significantly increased in the atmosphere. The concentration of the latter has reached such a value that a superstrong greenhouse effect has arisen. As a result, the water of the World Ocean practically boiled, its temperature became so high.

The appearance of vegetation everywhere on the surface of the Earth caused a fairly rapid absorption of carbon dioxide. Heat buildup has been reduced. A balance has been established. The average annual temperature on the surface of the planet was at a level close to the present.

The reasons

Strengthening the phenomenon contribute to:

• The development of industry is the main reason that carbon dioxide and other gases that enhance the greenhouse effect are actively emitted and accumulated in the atmosphere. The result of human activity on Earth is an increase in the average annual temperature. For a century, it has risen by 0.74 degrees. Scientists predict that in the future this growth could be 0.2 degrees for every 10 years. That is, the intensity of warming increases.
• - the reason for the increase in the concentration of CO2 in the atmosphere. This gas is absorbed by vegetation. The massive development of new lands, coupled with deforestation, accelerates the rate of accumulation of carbon dioxide, and at the same time changes the living conditions of animals and plants, leading to the extinction of their species.
• Combustion of fuel (solid and oil), waste leads to the release of carbon dioxide. Heating, electricity generation, transport are the main sources of this gas.
• The growth of energy consumption is a sign and condition of technical progress. The world population is increasing by about 2% per year. Growth in energy consumption - 5%. The intensity is increasing every year, humanity needs more and more energy.
• An increase in the number of landfills leads to an increase in the concentration of methane. Another source of gas is the activity of livestock complexes.

Threats

The consequences of the greenhouse effect can be detrimental to humans:

• The polar ice caps are melting, causing sea levels to rise. As a result, coastal fertile lands are under water. If flooding occurs at a high rate, there will be a serious threat to agriculture. Crops are dying, the area of ​​pastures is shrinking, sources of fresh water are disappearing. First of all, the low-income strata of the population, whose lives depend on the harvest, the growth of domestic animals, will suffer.
• Many coastal cities, including highly developed ones, may be under water in the future. For example, New York, St. Petersburg. Or entire countries. For example, Holland. Such phenomena will necessitate mass displacement of human settlements. Scientists suggest that in 15 years the ocean level may rise by 0.1-0.3 meters, and by the end of the 21st century - by 0.3-1 meter. In order for the above cities to be under water, the level must rise by about 5 meters.
• The increase in air temperature leads to the fact that within the continents the period of snow is reduced. It begins to melt earlier, as the rainy season ends faster. As a result, the soils are overdried, unsuitable for growing crops. Lack of moisture is the cause of desertification of lands. Experts say that an increase in average temperature by 1 degree in 10 years will lead to a reduction in forest areas by 100-200 million hectares. These lands will become steppes.
• The ocean covers 71% of our planet's surface area. As the air temperature rises, the water also heats up. Evaporation increases significantly. And this is one of the main reasons for the increase in the greenhouse effect.
• With rising water levels in the world's oceans, temperatures threaten biodiversity, and many species of wildlife may disappear. The reason is changes in their habitat. Not every species can successfully adapt to new conditions. The consequence of the disappearance of some plants, animals, birds, and other living beings is a violation of food chains, the balance of ecosystems.
• Rising water levels cause climate change. The boundaries of the seasons are shifting, the number and intensity of storms, hurricanes, and precipitation are increasing. Climate stability is the main condition for the existence of life on Earth. To stop the greenhouse effect means to save human civilization on the planet.
• High air temperature can adversely affect human health. Under such conditions, cardiovascular diseases are exacerbated, respiratory organs suffer. Thermal anomalies lead to an increase in the number of injuries, some psychological disorders. An increase in temperature entails a more rapid spread of many dangerous diseases, such as malaria and encephalitis.

What to do?

Today, the problem of the greenhouse effect is a global environmental issue. Experts believe that the widespread adoption of the following measures will help solve the problem:

• Changes in the use of energy sources. Reducing the share and quantity of fossils (carbon-containing peat, coal), oil. Switching to natural gas will significantly reduce CO2 emissions. Increasing the share of alternative sources (sun, wind, water) will reduce emissions, because these methods allow you to get energy without harm to the environment. When using them, gases are not emitted.
• Changing energy policy. Increasing the efficiency of power plants. Reducing the energy intensity of manufactured products at enterprises.
• Implementation of energy saving technologies. Even the usual insulation of the facades of houses, window openings, heating plants gives a significant result - fuel savings, which means less emissions. The solution of the issue at the level of enterprises, industries, states entails a global improvement in the situation. Each person can contribute to solving the problem: saving electricity, proper waste disposal, warming their own home.
• Development of technologies aimed at obtaining products in new, environmentally friendly ways.
• The use of secondary resources is one of the measures to reduce waste, the number and volume of landfills.
• Restoring forests, fighting fires in them, increasing the area as a way to reduce the concentration of carbon dioxide in the atmosphere.

The fight against greenhouse gas emissions today is carried out at the international level. World summits dedicated to this problem are being held, documents are being created aimed at organizing a global solution to the issue. Many scientists around the world are looking for ways to reduce the greenhouse effect, maintain balance and life on Earth.

The average surface temperature of the Earth (or another planet) rises due to the presence of an atmosphere.

Gardeners are well aware of this physical phenomenon. Inside the greenhouse is always warmer than outside, and this helps to grow plants, especially in the cold season. You may experience a similar effect when you are in a car. The reason for this is that the Sun, with a surface temperature of about 5000 ° C, emits mainly visible light - the part of the electromagnetic spectrum that our eyes are sensitive to. Since the atmosphere is largely transparent to visible light, solar radiation easily penetrates the Earth's surface. Glass is also transparent to visible light, so that the sun's rays enter the greenhouse and their energy is absorbed by plants and all objects inside. Further, according to the Stefan-Boltzmann law, each object radiates energy in some part of the electromagnetic spectrum. Objects with a temperature of about 15°C - the average temperature at the Earth's surface - radiate energy in the infrared range. Thus, the objects in the greenhouse emit infrared radiation. However, infrared radiation cannot easily pass through the glass, so the temperature inside the greenhouse rises.

A planet with a stable atmosphere, like Earth, experiences much the same effect—on a global scale. To maintain a constant temperature, the Earth itself needs to radiate as much energy as it absorbs from the visible light radiated towards us by the Sun. The atmosphere serves as a kind of glass in a greenhouse - it is not as transparent to infrared radiation as it is to sunlight. Molecules of various substances in the atmosphere (the most important of them are carbon dioxide and water) absorb infrared radiation, acting as greenhouse gases. Thus, infrared photons emitted by the earth's surface do not always go straight into space. Some of them are absorbed by greenhouse gas molecules in the atmosphere. When these molecules re-radiate the energy they have absorbed, they can radiate it both towards space and inward, back to the surface of the Earth. The presence of such gases in the atmosphere creates the effect of covering the Earth with a blanket. They cannot stop heat from escaping to the outside, but they allow heat to remain near the surface for a longer time, so the Earth's surface is much warmer than it would be in the absence of gases. Without the atmosphere, the average surface temperature would be -20°C, well below the freezing point of water.

It is important to understand that the greenhouse effect has always existed on Earth. Without the greenhouse effect caused by the presence of carbon dioxide in the atmosphere, the oceans would have frozen over long ago, and higher forms of life would not have appeared. Currently, the scientific debate about the greenhouse effect is on the issue global warming: Are we humans disturbing the planet's energy balance too much as a result of burning fossil fuels and other economic activities, while adding an excessive amount of carbon dioxide to the atmosphere? Today, scientists agree that we are responsible for increasing the natural greenhouse effect by several degrees.

The greenhouse effect takes place not only on Earth. In fact, the strongest greenhouse effect we know of is on the neighboring planet, Venus. The atmosphere of Venus is almost entirely composed of carbon dioxide, and as a result, the surface of the planet is heated to 475 ° C. Climatologists believe that we have avoided such a fate thanks to the presence of oceans on Earth. The oceans absorb atmospheric carbon and it accumulates in rocks such as limestone, thereby removing carbon dioxide from the atmosphere. There are no oceans on Venus, and all the carbon dioxide emitted into the atmosphere by volcanoes remains there. As a result, we observe on Venus ungovernable Greenhouse effect.

The greenhouse effect is the delay by the Earth's atmosphere of the planet's thermal radiation. The greenhouse effect was observed by any of us: in greenhouses or greenhouses the temperature is always higher than outside. The same is observed on the scale of the Earth: solar energy, passing through the atmosphere, heats the surface of the Earth, but the thermal energy emitted by the Earth cannot escape back into space, since the Earth's atmosphere delays it, acting like polyethylene in a greenhouse: it transmits short light waves from the Sun to the Earth and delays long thermal (or infrared) waves emitted by the Earth's surface. There is a greenhouse effect. The greenhouse effect occurs due to the presence of gases in the Earth's atmosphere that have the ability to delay long waves. They are called "greenhouse" or "greenhouse" gases.

Greenhouse gases have been present in the atmosphere in small amounts (about 0.1%) since its formation. This amount was enough to maintain the Earth's heat balance at a level suitable for life due to the greenhouse effect. This is the so-called natural greenhouse effect, if it were not for it, the average temperature of the Earth's surface would be 30 ° C not +15°C, as it is now, but -18°C.

The natural greenhouse effect does not threaten either the Earth or humanity, since the total amount of greenhouse gases was maintained at the same level due to the cycle of nature, moreover, we owe our lives to it.

But an increase in the concentration of greenhouse gases in the atmosphere leads to an increase in the greenhouse effect and a violation of the heat balance of the Earth. This is exactly what happened in the last two centuries of the development of civilization. Coal-fired power plants, car exhausts, factory chimneys and other man-made sources of pollution emit about 22 billion tons of greenhouse gases per year into the atmosphere.

What gases are called "greenhouse" gases?

The best known and most common greenhouse gases are water vapor(H 2 O), carbon dioxide(CO2), methane(CH 4) and laughing gas or nitrous oxide (N 2 O). These are direct greenhouse gases. Most of them are formed during the combustion of fossil fuels.

In addition, there are two more groups of direct greenhouse gases, these are halocarbons and sulfur hexafluoride(SF6). Their emissions into the atmosphere are associated with modern technologies and industrial processes (electronics and refrigeration equipment). Their amount in the atmosphere is quite negligible, but their impact on the greenhouse effect (the so-called global warming potential / GWP) is tens of thousands of times stronger than CO 2 .

Water vapor is the main greenhouse gas responsible for more than 60% of the natural greenhouse effect. An anthropogenic increase in its concentration in the atmosphere has not yet been noted. However, an increase in the Earth's temperature, caused by other factors, increases the evaporation of ocean water, which can lead to an increase in the concentration of water vapor in the atmosphere and - to an increase in the greenhouse effect. On the other hand, clouds in the atmosphere reflect direct sunlight, which reduces the flow of energy to the Earth and, accordingly, reduces the greenhouse effect.

Carbon dioxide is the best known of the greenhouse gases. Natural sources of CO 2 are volcanic emissions, vital activity of organisms. Anthropogenic sources are the combustion of fossil fuels (including forest fires) as well as a range of industrial processes (eg cement production, glass production). Carbon dioxide, according to most researchers, is primarily responsible for global warming caused by the "greenhouse effect". CO 2 concentrations have risen by more than 30% over two centuries of industrialization and are correlated with changes in global average temperature.

Methane is the second most important greenhouse gas. It is emitted due to leakage in the development of deposits of coal and natural gas, from pipelines, during the combustion of biomass, in landfills (as an integral part of biogas), as well as in agriculture (cattle breeding, rice growing), etc. Animal husbandry, fertilizer application, coal burning and other sources produce about 250 million tons of methane per year. The amount of methane in the atmosphere is small, but its greenhouse effect or global warming potential (GWP) is 21 times stronger than that of CO 2 .

Nitrous oxide is the third most important greenhouse gas: its impact is 310 times stronger than that of CO 2, but it is found in the atmosphere in very small quantities. It enters the atmosphere as a result of the vital activity of plants and animals, as well as in the production and use of mineral fertilizers, the work of chemical industry enterprises.

Halocarbons (hydrofluorocarbons and perfluorocarbons) are gases created to replace ozone-depleting substances. They are mainly used in refrigeration equipment. They have exceptionally high coefficients of influence on the greenhouse effect: 140-11700 times higher than those of CO 2. Their emissions (release into the environment) are small, but are growing rapidly.

Sulfur hexafluoride - its entry into the atmosphere is associated with electronics and the production of insulating materials. While it is small, but the volume is constantly increasing. The global warming potential is 23900 units.