Carbon dioxide plays an important role in the greenhouse effect. With the development of industrial revolution, more and more people get a lot of fossil fuels as energy from the earth. Fossil fuels release a lot of carbon dioxide during combustion, which greatly increases the concentration of carbon dioxide in the atmosphere and intensifies the greenhouse effect. The increase of carbon dioxide concentration is still caused by people's lack of ecological environment knowledge and massive deforestation and land reclamation in pursuit of short-term interests. The forest is a good friend of mankind, a famous air purifier and the general dispatching room of nature. It stores carbon dioxide in the form of organic carbon by breathing. When the forest is destroyed, the carbon dioxide originally stored in organic form is oxidized and released into the atmosphere, which greatly increases the concentration of carbon dioxide in the atmosphere.
Of all the greenhouse gases, only Freon does not exist in nature, it is purely manufactured by human beings in industry. Humans use freon to make refrigerants for refrigerators, industrial sprays, pesticides in farmland and foaming agents and cleaning agents in the chemical industry. In fact, humans also make "ozone killers" and "greenhouse effect initiators".
The intensification of the greenhouse effect will have a great impact on the global environment, and the most obvious is that the temperature zone and rainfall zone will change accordingly. Take China as an example. If the global temperature rises by 3.5 degrees, the northern boundary of subtropics will move from Qinling-Huaihe region to the north of the Yellow River. Then the winter temperature in Xuzhou and Zhengzhou will be similar to that in Hangzhou and Wuhan now. The climate in Iceland near the Arctic Circle may be similar to that in northern Scotland today. In addition, residents in coastal areas are more worried that sea level rise caused by greenhouse effect is a potential threat to mankind.
Since 1980s, the global warming caused by the global greenhouse effect is very obvious. Experts estimate that the temperature will rise by 100 in the future, and the international community is highly concerned about this. During the period of 1988, the United Nations established the Intergovernmental Panel on Climate Change (IPCC), which specially organized the timely investigation of greenhouse gas emission inventories and assessed the status and impact of climate change. 1992, the Committee of the United Nations Framework Convention on Climate Change was established to be responsible for the inventory investigation of industrial greenhouse gases in various countries. In order to control global climate change, what we should do is to control greenhouse gas emissions. What is the greenhouse effect? What are the disadvantages?
Greenhouse has two characteristics: the temperature is higher than that outside, and it does not dissipate heat. Glass greenhouses and vegetable greenhouses that can be seen in life are typical greenhouses. Glass or transparent plastic film is used as a greenhouse, so that sunlight can directly shine into the greenhouse and heat the indoor air, and the glass or transparent plastic film can prevent the indoor hot air from emitting outward, thus keeping the indoor temperature higher than the outside and providing conditions conducive to the rapid growth of plants.
The greenhouse effect caused by environmental pollution refers to the phenomenon that the earth's surface becomes hot.
It will bring the following serious consequences:
1) the increase of pests and diseases on the earth;
2) sea level rise;
3) Abnormal climate, increasing ocean storms;
4) The land is dry and the desertification area increases.
Scientists predict that if the earth's surface temperature continues to rise at the current rate, by 2050, the global temperature will rise by 2-4 degrees Celsius, polar icebergs will melt greatly, resulting in a sharp rise in sea level, and some island countries and coastal cities will be submerged, including several famous international cities: new york, Shanghai, Tokyo and Sydney.
How is the greenhouse effect produced? What can we do?
The greenhouse effect is mainly caused by excessive burning of coal, oil and natural gas in modern industrial society, which releases a lot of carbon dioxide gas into the atmosphere after burning.
Carbon dioxide gas has the functions of heat absorption and heat insulation. The result of its increase in the atmosphere is the formation of an invisible glass cover, which prevents the heat radiated by the sun to the earth from spreading to outer space, and as a result, the surface of the earth becomes hot. Therefore, carbon dioxide is also called greenhouse gas.
Human activities and nature also emit other greenhouse gases, such as chlorofluorocarbons (CFCs), methane, low-level ozone and nitrogen oxides. On earth, plankton in the ocean and forests on land, especially tropical rainforests, can absorb a lot of carbon dioxide.
In order to reduce the excessive carbon dioxide in the atmosphere, on the one hand, people need to save electricity as much as possible (because power generation needs to burn coal) and drive less cars. On the other hand, protect forests and oceans, for example, don't cut down forests and prevent the oceans from being polluted, so as to protect the survival of plankton. We can also protect green plants by planting trees, reducing the use of disposable wooden chopsticks, saving paper (paper-making wood) and not trampling on the lawn, so that they can absorb more carbon dioxide and help slow down the greenhouse effect.
In recent years, the simulation ability of climate model has been greatly improved, mainly considering the role of aerosols (tiny particles suspended in the air) in the atmosphere. Because when burning fossil fuels, it will release CO2, and at the same time, it will release huge aerosols such as sulfides. This aerosol will prevent some sunlight from reaching the ground, thus reducing the ground temperature and playing a role in cooling down. The IPCC estimated it to be -0.5 W/m2. That is, 1/3 is equivalent to the warming effect of CO2 (1.56W/m2), which is slightly greater than that of methane (+0.47W/m2). Mainly based on this improvement, in the second report published in 1996, IPCC changed the warming value of global average temperature after CO2 doubling of 2 100 from 1.5℃-4.5℃ to 1.0℃-3.5℃. The assessment report also pointed out that due to the huge thermal inertia of the ocean, the warming value of 2 100 will only be about 50%-90%.
However, the results of model calculation also show that the global average warming 1.0℃-3.5℃ is unevenly distributed around the world, but there is no or almost no warming in equatorial and tropical areas, and the warming is mainly concentrated in high latitudes, with the amount reaching 6℃-8℃ or even more. This will cause another serious consequence, that is, the ice sheets at the poles and Greenland will melt, causing sea levels to rise. The permafrost zone of the high-latitude continent in the northern hemisphere will also melt or thin, resulting in a large area of swamp. In addition, the volume expansion of seawater after ocean warming will also lead to sea level rise. In the first assessment report of IPCC, it is predicted that the sea level will rise by 70- 150 cm (corresponding temperature rise 1.5℃-4.5℃), and in the second assessment report, it will be 20% lower than the first assessment result (corresponding temperature rise 1.0℃-3.5℃). The IPCC's second assessment report also pointed out that the global sea level has risen by10-25cm since the end of 19, because the global average temperature has risen by 0.3℃-0.6℃.
The rise of global sea level will directly flood the coastal lowlands with dense population and developed industry and agriculture, with very serious consequences. 1995165438+1At the second Conference of the Parties to the United Nations Framework Convention on Climate Change held in Berlin in October, 44 small island countries formed the Alliance of Small Island States and called for the right to exist.
In addition, it is pointed out that the increase of CO2 will not only lead to global warming, but also lead to the adjustment of global atmospheric circulation and the expansion of climatic zones to the polar regions. The precipitation in mid-latitude areas, including northern China, will decrease, and evaporation will increase as the temperature rises, so the climate will become drier. The adjustment of atmospheric circulation, in addition to mid-latitude drought, may also cause climate anomalies and disasters in other parts of the world. For example, the intensity of typhoons at low latitudes will increase, and the source of typhoons will expand northward. Rising temperature will also cause and aggravate the epidemic of infectious diseases. Take malaria as an example. In the past five years, the incidence of malaria in the world has quadrupled. At present, about 500 million people in the world suffer from malaria every year, and more than 2 million of them die.
However, the greenhouse effect is not all bad. Because the coldest high latitudes have the greatest warming, agricultural areas will be greatly promoted to the polar regions. The increase of CO2 is also beneficial to the photosynthesis of plants and directly increases the yield of organic matter. It is also pointed out that in the historical period of China and the world, the warm period is mostly a prosperous period with more precipitation and shrinking arid areas, and so on.
Of course, there are also different views on the issue of atmospheric greenhouse effect. For example, some scientists used to think that the current numerical model is immature and the calculation results are too exaggerated; A rise of 0.3℃-0.6℃ in a hundred years is a normal climate change, which cannot be proved to be caused by the atmospheric greenhouse effect, and so on. Of course, this is a minority opinion.
However, the indisputable fact is that the concentration of CO2 in the atmosphere and the global temperature are increasing rapidly, and the increase of greenhouse gases will lead to global warming. If we wait until the problem is clearly perceived by human beings, it will often be difficult to reverse it, and it will be too late. Therefore, we must attach great importance to it now in order to take countermeasures to protect the atmospheric environment on which human beings depend.