The greenhouse effect is associated with an increase. The greenhouse effect has always been

The concept of "greenhouse effect" is well known to all gardeners and gardeners. Inside the greenhouse, the air temperature is higher than in the open air, which makes it possible to grow vegetables and fruits even in the cold season.


Similar phenomena occur in the atmosphere of our planet, but have a more global scale. What is the greenhouse effect on Earth and what consequences can its strengthening have?

What is the greenhouse effect?

Greenhouse effect- this is an increase in the average annual air temperature on the planet, occurring due to a change in the optical properties of the atmosphere. It is easier to understand the essence of this phenomenon using the example of an ordinary greenhouse, which is available on any personal plot.

Imagine that the atmosphere is glass walls and the roof of a greenhouse. Like glass, it easily passes the sun's rays through itself and delays the radiation of heat from the earth, preventing it from escaping into space. As a result, heat remains above the surface and heats the surface layers of the atmosphere.

Why does the greenhouse effect occur?

The reason for the appearance of the greenhouse effect is the difference between radiation and the earth's surface. The sun with its temperature of 5778 ° C gives mainly visible light, highly sensitive to our eyes. Since the air is able to transmit this light, the sun's rays easily pass through it and heat the earth's shell. Objects and objects near the surface have an average temperature of about +14 ... +15 ° C, therefore they emit energy in the infrared range, which is not able to pass through the atmosphere in full.


For the first time, such an effect was modeled by the physicist Philippe de Saussure, who exposed a vessel covered with a glass lid to the sun, and then measured the temperature difference between inside and outside. Inside, the air turned out to be warmer, as if the vessel received solar energy from outside. In 1827, the physicist Joseph Fourier suggested that such an effect could also occur with the Earth's atmosphere, influencing the climate.

It was he who concluded that the temperature in the "greenhouse" rises due to the different transparency of the glass in the infrared and visible ranges, as well as due to the prevention of the outflow of warm air by the glass.

How does the greenhouse effect affect the planet's climate?

With constant fluxes of solar radiation climatic conditions And mean annual temperature on our planet depend on its heat balance, as well as on the chemical composition and air temperature. The higher the level of greenhouse gases near the surface (ozone, methane, carbon dioxide, water vapor), the higher the likelihood of an increase in the greenhouse effect and, accordingly, global warming. In turn, a decrease in the concentration of gases leads to a decrease in temperature and the appearance of an ice cover in the polar regions.


Due to the reflectivity of the earth's surface (albedo), the climate on our planet has repeatedly passed from the stage of warming to the stage of cooling, so the greenhouse effect itself is not a particular problem. However, in last years as a result of atmospheric pollution by exhaust gases, emissions from thermal power plants and various factories on Earth, an increase in the concentration of carbon dioxide is observed, which can lead to global warming and negative consequences for all mankind.

What are the consequences of the greenhouse effect?

If over the past 500 thousand years the concentration of carbon dioxide on the planet has never exceeded 300 ppm, then in 2004 this figure was 379 ppm. What threatens our Earth? First of all, the increase in ambient temperature and global cataclysms.

Melting glaciers can significantly raise the level of the world's oceans and thereby cause coastal flooding. It is believed that 50 years after the increase in the greenhouse effect on geographical map most of the islands may not remain, all seaside resorts on the continents will disappear under the ocean water.


Warming at the poles can change the distribution of precipitation throughout the earth: in some areas their number will increase, in others it will decrease and lead to drought and desertification. Negative Consequence growth in the concentration of greenhouse gases is also the destruction of the ozone layer, which will reduce the protection of the planet's surface from ultraviolet rays and lead to the destruction of DNA and molecules in the human body.

The expansion of ozone holes is also fraught with the loss of many microorganisms, in particular marine phytoplankton, which can have a significant impact on the animals that feed on them.

St. Petersburg College of Management and Economics

"Alexander Lyceum"

Report on the environmental fundamentals of nature management on the topic:

"Greenhouse effect"

Performed

group student №105

Vorozhbinova Sofia.

St. Petersburg, 2011

GREENHOUSE EFFECT

The greenhouse effect is a rise in temperature on the surface of the planet as a result of thermal energy that appears in the atmosphere due to the heating of gases. The main gases that lead to the greenhouse effect on Earth are water vapor and carbon dioxide.

The phenomenon of the greenhouse effect makes it possible to maintain a temperature on the Earth's surface at which the emergence and development of life is possible. If there were no greenhouse effect, average temperature the surface of the globe would be much lower than it is now. However, as the concentration of greenhouse gases rises, the atmosphere's impermeability to infrared rays increases, which leads to an increase in the temperature of the Earth.

In 2007, the Intergovernmental Panel on Climate Change (IPCC) - the most authoritative international body that brings together thousands of scientists from 130 countries of the world - presented its Fourth Assessment Report, which contained generalized conclusions about past and current climate change, their impact on nature and humans , as well as possible measures to counteract such changes.

According to published data, from 1906 to 2005, the average temperature of the Earth rose by 0.74 degrees. In the next 20 years, the temperature increase, according to experts, will average 0.2 degrees per decade, and by the end of the 21st century, the Earth's temperature may increase from 1.8 to 4.6 degrees (such a difference in the data is the result of superimposing a whole range of models future climate, which took into account various scenarios for the development of the world economy and society).

According to scientists, with a 90 percent probability, observed climate changes are associated with human activities - the burning of carbon fossil fuels (i.e. oil, gas, coal, etc.), industrial processes, as well as the deforestation - natural sinks of carbon dioxide from the atmosphere .

climate change impacts:

1. Change in the frequency and intensity of precipitation.

In general, the climate on the planet will become more humid. But the amount of precipitation will not spread evenly across the Earth. In regions that already receive enough rainfall today, their fallout will become more intense. And in regions with insufficient moisture, dry periods will become more frequent.

2. Sea level rise.

During the 20th century, the average sea level rose by 0.1-0.2 m. According to scientists, in the 21st century, the sea level rise will be up to 1 m. In this case, coastal areas and small islands will be the most vulnerable. States such as the Netherlands, Great Britain, as well as the small island states of Oceania and the Caribbean will be the first to fall under the risk of flooding. In addition, high tides will become more frequent, and coastal erosion will increase.

3. Threat to ecosystems and biodiversity.

There are forecasts for the extinction of up to 30-40% of plant and animal species, as their habitat will change faster than they can adapt to these changes.

With an increase in temperature by 1 degree, a change in the species composition of the forest is predicted. Forests are a natural carbon store (80% of all carbon in terrestrial vegetation and about 40% of carbon in soil). The transition from one type of forest to another will be accompanied by the release of a large amount of carbon.

4. Melting glaciers.

The current glaciation of the Earth can be considered one of the most sensitive indicators of ongoing global changes. Satellite data show that since the 1960s there has been a decrease in the area of ​​snow cover by about 10%. Since the 1950s, in the Northern Hemisphere, the sea ice area has decreased by almost 10-15%, and the thickness has decreased by 40%. According to forecasts by experts from the Arctic and Antarctic Research Institute (St. Petersburg), in 30 years the Arctic Ocean will completely open from under the ice during the warm period of the year.

According to scientists, the thickness of the Himalayan ice is melting at a rate of 10-15 m per year. At the current rate of these processes, two-thirds of the glaciers will disappear by 2060, and by 2100 all glaciers will have completely melted.
Accelerated glacier melt poses a range of immediate threats human development. For densely populated mountainous and foothill areas, avalanches, flooding or, conversely, a decrease in the full flow of rivers, and as a result, a reduction in fresh water reserves, are of particular danger.

5. Agriculture.

The impact of warming on agricultural productivity is ambiguous. In some temperate areas, yields may increase with a small increase in temperature, but decrease with large changes in temperature. In tropical and subtropical regions, overall yields are projected to decline.

The worst hit could be inflicted on the poorest countries least prepared to adapt to climate change. According to the IPCC, by 2080 the number of people facing the threat of hunger could increase by 600 million, twice the number of people living in poverty today in sub-Saharan Africa.

6. Water consumption and water supply.

One of the consequences of climate change could be a lack of drinking water. In regions with arid climates (Central Asia, the Mediterranean, South Africa, Australia, etc.), the situation will be further aggravated due to a decrease in precipitation.
Due to the melting of glaciers, the flow of the largest waterways in Asia - the Brahmaputra, Ganges, Yellow River, Indus, Mekong, Salween and Yangtze - will significantly decrease. The lack of fresh water will affect not only human health and agricultural development, but will also increase the risk of political divisions and conflicts over access to water resources.

7. Human health.

Climate change, according to scientists, will lead to increased health risks for people, especially for the poorer segments of the population. Thus, a reduction in food production will inevitably lead to malnutrition and hunger. Abnormally high temperatures can exacerbate cardiovascular, respiratory and other diseases.

Rising temperatures may change the geographic distribution of various disease vector species. As temperatures rise, the ranges of heat-loving animals and insects (such as encephalitic mites and malaria mosquitoes) will spread further north, while the people inhabiting these areas will not be immune to new diseases.

According to environmentalists, humanity is unlikely to be able to prevent completely predictable climate change. However, it is in human power to mitigate climate change, to restrain the rate of temperature increase in order to avoid dangerous and irreversible consequences in the future. First of all, due to:

1. Restrictions and reductions in the consumption of fossil carbon fuels (coal, oil, gas);
2. Improving the efficiency of energy consumption;
3. Implementation of energy saving measures;
4. Greater use of non-carbon and renewable energy sources;
5. Development of new environmentally friendly and low-carbon technologies;
6. Through the prevention of forest fires and the restoration of forests, since forests are natural sinks of carbon dioxide from the atmosphere.

The greenhouse effect takes place not only on Earth. A strong greenhouse effect 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 degrees. Climatologists believe that the Earth avoided such a fate due to the presence of oceans on it. 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, an uncontrollable greenhouse effect is observed on the planet.

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), and whole line industrial processes (eg cement, 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 component 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.

The greenhouse effect is an increase in the temperature of the earth's surface due to the heating of the lower atmosphere by the accumulation of greenhouse gases. As a result, the air temperature is higher than it should be, and this leads to such irreversible consequences as climate change and global warming. Several centuries ago this ecological problem existed, but was not so obvious. With the development of technology, the number of sources that provide the greenhouse effect in the atmosphere is increasing every year.

Causes of the greenhouse effect

the use of combustible minerals in industry - coal, oil, natural gas, the combustion of which releases a huge amount of carbon dioxide and other harmful compounds into the atmosphere;

transport - cars and trucks emit exhaust gases, which also pollute the air and increase the greenhouse effect;

deforestation, which absorb carbon dioxide and release oxygen, and with the destruction of every tree on the planet, the amount of CO2 in the air increases;

forest fires are another source of destruction of plants on the planet;

an increase in the population affects the increase in the demand for food, clothing, housing, and to ensure this, it is growing industrial production, which is increasingly polluting the air with greenhouse gases;

agrochemicals and fertilizers contain varying amounts of compounds that release nitrogen, one of the greenhouse gases, as a result of evaporation;

the decomposition and burning of garbage in landfills contribute to the increase in greenhouse gases.

The impact of the greenhouse effect on climate

Considering the results of the greenhouse effect, it can be determined that the main one is climate change. Since the air temperature rises every year, the waters of the seas and oceans evaporate more intensively. Some scientists predict that in 200 years such a phenomenon as the "drying" of the oceans, namely a significant decrease in water levels, will become noticeable. This is one side of the problem. The other is that the increase in temperature leads to the melting of glaciers, which contributes to the rise in the water level of the World Ocean, and leads to the flooding of the coasts of continents and islands. The increase in the number of floods and flooding of coastal areas indicates that the level of ocean waters is increasing every year.

An increase in air temperature leads to the fact that areas that are little moistened by precipitation become arid and unsuitable for life. Here, crops are dying, which leads to a food crisis for the population of the area. Also, there is no food for animals, because plants die out due to lack of water.

First of all, we need to stop deforestation, plant new trees and shrubs, as they absorb carbon dioxide and produce oxygen. Using electric vehicles will reduce the amount of exhaust gases. In addition, you can change from cars to bicycles, which is more convenient, cheaper and safer for the environment. Alternative fuels are also being developed, which, unfortunately, is slowly being introduced into our daily lives.

19. Ozone layer: value, composition, possible causes of its destruction, protection measures taken.

Earth's ozone layer Ozone is a region of the Earth's atmosphere where ozone is produced, a gas that protects our planet from the harmful effects of ultraviolet radiation.

Destruction and depletion of the Earth's ozone layer.

The ozone layer, despite its great importance for all living things, is a very fragile barrier to ultraviolet rays. Its integrity depends on a number of conditions, but nature nevertheless came to a balance in this matter, and for many millions of years the Earth's ozone layer successfully coped with the mission assigned to it. The processes of formation and destruction of the ozone layer were strictly balanced until man appeared on the planet and in his development did not reach the current technical level.

In the 70s. of the twentieth century, it was proved that many substances actively used by man in economic activities can significantly reduce the level of ozone in Earth's atmosphere.

Substances that deplete the Earth's ozone layer include fluorochlorocarbons - freons (gases used in aerosols and refrigerators, consisting of chlorine, fluorine and carbon atoms), combustion products during high-altitude aviation flights and rocket launches, i.e. substances whose molecules contain chlorine or bromine.

These substances, released into the atmosphere near the Earth's surface, reach the upper limit in 10–20 years. the boundaries of the ozone layer. There, under the influence of ultraviolet radiation, they decompose, forming chlorine and bromine, which, in turn, interacting with stratospheric ozone, significantly reduce its amount.

Causes of destruction and depletion of the ozone layer of the Earth.

Let us consider once again in more detail the causes of the destruction of the Earth's ozone layer. At the same time, we will not consider the natural decay of ozone molecules. We will focus on human economic activity.

Gardeners are well aware of this physical phenomenon, as it is always warmer inside the greenhouse than outside, and this helps plants grow, especially during the cold season.

You can feel the same effect when you are in a car on a sunny day. The reason for it is that the sun's rays pass through the glass inside the greenhouse, and their energy is absorbed by plants and all objects inside. Then the same objects, plants radiate their energy, but it can no longer penetrate the glass, so the temperature inside the greenhouse rises.

A planet with a stable atmosphere, such as Earth, experiences much the same effect. To maintain a constant temperature, the Earth itself needs to radiate as much energy as it receives. The atmosphere serves as a glass in a greenhouse.

The greenhouse effect was first discovered by Joseph Fourier in 1824 and was first studied quantitatively in 1896. The greenhouse effect is the process by which the absorption and emission of infrared radiation by atmospheric gases causes the atmosphere and surface of a planet to heat up.

Earth's warm blanket

On Earth, the main greenhouse gases are:

1) water vapor (responsible for approximately 36-70% of the greenhouse effect);

2) carbon dioxide (CO2) (9-26%);

3) methane (CH4) (4-9%);

4) ozone (3-7%).

The presence of such gases in the atmosphere creates the effect of covering the Earth with a blanket. They allow you to keep heat near the surface for more for a long time, so the surface of the Earth is much warmer than it would be in the absence of gases. Without the atmosphere, the average surface temperature would be -20°C. In other words, in the absence of the greenhouse effect, our planet would be uninhabited.

The strongest greenhouse effect

The greenhouse effect takes place not only on Earth. In fact, the strongest greenhouse effect that 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. There are no oceans on Venus, and all the carbon dioxide emitted into the atmosphere by volcanoes remains there. As a result, we are seeing an uncontrolled greenhouse effect on Venus that makes life on this planet impossible.

The planet Venus is experiencing an unmanageable greenhouse effect, and seemingly gentle clouds hide a scalding hot surface.

The greenhouse effect has always been

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. In essence, not the climate, but the fate of life on Earth depends entirely on whether a certain amount of carbon dioxide remains in the atmosphere or disappears, and then life on Earth will cease. Paradoxically, it is mankind that can prolong life on Earth for some time by returning to circulation at least part of the carbon dioxide reserves from coal, oil and gas fields.

Currently, the scientific debate about the greenhouse effect is on the issue of global warming: are we, humans, disturbing the energy balance of the planet too much as a result of burning fossil fuels and other economic activities, while adding an excessive amount of carbon dioxide to the atmosphere, thereby reducing the amount of oxygen in her? Today, scientists agree that we are responsible for increasing the natural greenhouse effect by several degrees.

Let's do an experiment

Let's try to show the result of the action of increasing carbon dioxide in the experiment.

Pour a glass of vinegar into the bottle and put a few crystals of soda in it. We fix a straw in the cork and close the bottle tightly with it. Place the bottle in a wide glass, place lighted candles of various heights around it. Candles will begin to go out, starting with the shortest one.

Why is this happening? Carbon dioxide begins to accumulate in the glass and oxygen is displaced. It also happens on Earth, i.e. the planet begins to experience a lack of oxygen.

What does this threaten us with?

So, what are the causes of the greenhouse effect, we have seen. But why is everyone so afraid of him? Let's consider its consequences:

1. If the temperature on Earth continues to rise, this will have a major impact on the global climate.

2. More precipitation will fall in the tropics, as additional heat will increase the amount of water vapor in the air.

3. In arid regions, the rains will become even more rare and they will turn into deserts, as a result of which people and animals will have to leave them.

4. The temperature of the seas will also rise, which will lead to the flooding of low-lying areas of the coast and to an increase in the number of powerful storms.

5. Residential land will shrink.

6. If the temperature on Earth rises, many animals will not be able to adapt to climate change. Many plants will die from lack of water and animals will have to move to other places in search of food and water. If the increase in temperature leads to the death of many plants, then many animal species will die out after them.

7. Temperature change is bad for people's health.

8. In addition to the negative consequences of global warming, one can also note a positive consequence. Global warming make the climate of Russia better. At first glance, a warmer climate appears to be a boon. But the potential gain may be wiped out by the harm from diseases caused by harmful insects, as the rise in temperature will hasten their reproduction. Lands in some regions of Russia will be unsuitable for habitation

It's time to act!

Coal-fired power plants, car exhausts, factory chimneys and other man-made sources of pollution together emit about 22 billion tons of carbon dioxide and other greenhouse gases per year. Animal husbandry, fertilizer application, coal burning and other sources produce about 250 million tons of methane per year. About half of all greenhouse gases emitted by mankind remain in the atmosphere. About three-quarters of all greenhouse gas emissions over the past 20 years have been caused by the use of oil, natural gas and coal. Much of the rest is caused by landscape changes, primarily deforestation.

Human activities lead to an increase in the concentration of greenhouse gases in the atmosphere.

But the time has come to work just as purposefully on how to give back to nature what we take from it. A person is able to solve this grandiose problem and urgently begin to act to protect our Earth:

1. Restoration of soil and vegetation cover.

2. Decreased consumption of fossil fuels.

3. Wider use of water, wind, solar energy.

4. Combat air pollution.