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"Ozone hole"
Chlorine, fluorine, and carbon gases form the freon group and are also actively involved in greenhouse effect. These gases have been accumulating in the atmosphere since the 1950s, increasing by 5-10% per year. They are commonly used in the manufacture of refrigerators and heaters, in the manufacture of foam plastic products, and so on. At an altitude of 1525 km above the Earth's surface, the ozone layer, that is, triatomic oxygen (O3), is released. It forms a unique shell ozone screen. This layer absorbs ultraviolet light from the Sun and protects life on Earth from radiation. Freon group gases, especially 1 atom of chlorine, destroy 100,000 ozone molecules. Atoms of the freon group in the present atmosphere have the ability to survive even after 100 years. Ozone depletion was first observed in the sky in Antarctica in 1985, when it came to be known as the “ozone hole”. The "ozone hole" was also observed in 1995-96 in densely populated North America, Asia and Europe.
In order to prevent ozone depletion, the Montreal Accord was signed in 1987 in Montreal with the participation of representatives from 24 countries. It agreed to reduce freon production by 50% by 1999. In 1989, at an international conference in London entitled "Save the Ozone Layer", representatives of 120 countries exchanged views on how to solve this problem. In May 1989, it was received by scientists and government officials from 81 countries. “The Helsinki Declaration on the Protection of the Ozone Layer sets out measures to gradually reduce the production of freon gases by the year 2000.
Desertification. It is another global environmental problem on earth. The sharp increase in the area of flowers in the arid climate since the 60s is primarily due to the steady increase in population in developing countries. According to the United Nations, 95% of the arid and low-rainfall climate zones are now on the verge of desertification. In arid climates, the total area of the earth is about 40 million hectares. km2, or about 25% of the land.
The arid climate zone is home to 20% of the Earth's population (800 million people). Desertification is also occurring in Uzbekistan. Due to the fact that more than 70% of the country's territory is located in desert and semi-desert areas, such events as salinization wind, and water erosion in irrigated lands, rising groundwater levels in pastures occur in large areas in recent years. On October 31, 1995, the Republic of Uzbekistan signed the International Conference on Combating Drought and Desertification.
Problems along the Aral Sea. At present, as a result of the 18 m drop in the Aral Sea level, it has now become 2 residual lakes. Its shores are 60-80 km. retreated. The seabed is 4 million feet deep. seen in an area of more than. The result was a sandy sandy desert. Dust storms on the dried bottom of the island are observed for 90 days every year, the dust reaches an area of 400 km in length and 40 km in width. 75 million tons are released into the atmosphere every year. rising to. All this is leading to climate change and changes in the natural environment leading to environmental catastrophe, as well as the emergence of various diseases, especially jaundice and anemia. The following factors can cause environmental problems.
1) The impact of industry;
2) Agriculture;
3) Motor transport;
4) Influence of demographic factors.
5) The impact of various anthropogenic factors on nature, etc.
The fate of the future development of mankind depends, in many respects, on finding ways and means to optimally resolve the contradictions between nature and society. Therefore, it is necessary to strictly adhere to the 6 basic principles of the relationship between nature and society. 1. There must be a favorable harmony between nature and society. In doing so, the assimilation of energy and matter by man must be similar and consistent with natural processes. First and foremost, society must be able to balance the biosphere.
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