Environmental crisis
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The document discusses ozone depletion and its causes and effects. It states that the ozone layer was discovered to be depleting in the 1980s due to CFC emissions. Antarctica has seen significant ozone destruction, with a hole forming over it that threatens both Antarctica and other areas if Antarctica's icecaps melt. CFCs released into the stratosphere cause chlorine atoms to break down ozone molecules, with one chlorine able to destroy over 100,000 ozone molecules. Ozone depletion leads to increased UV radiation, which can cause skin cancer in humans and affect plants, animals, and ecosystems. Many countries have signed treaties restricting CFCs to address the problem.
Environmental crisis
- 2. In recent years, the ozone depletion has been the subject of much discussion because the ozone layer effects both plant and animal life on the planet. The fact that the ozone layer was being depleted was discovered in the mid-1980s. The main cause of this is the release of CFCs, chlorofluorocarbons. Antarctica was an early victim of ozone destruction. A massive hole in the ozone layer right above Antarctica now threatens not only that continent, but many others that could be the victims of Antarctica's melting icecaps
- 3. Production and emission of CFCs . CFCs is mainly caused in the stratosphere. There, the chlorine atom is removed from the CFC and attracts one of the three oxygen atoms in the ozone molecule. The process continues, and a single chlorine atom can destroy over 100,000 molecules of ozone.
- 4. Every time 1% of the ozone layer is depleted, 2% more UV-B is able to reach the surface of the planet. UV-B increase is one of the most harmful consequences of ozone depletion because it can cause skin cancer. Causes malaria and other infectious diseases. Life cycles of plants will also be affected ,therefore disturbed food chains . Effects on animals will also be severe. Affect physiological and developmental processes in plants.
- 5. Many countries have signed treaties and written laws restricting the use of CFCs. Give awareness to the people about the dangers of ozone depletion . Campaigns should also be done to find out the substitutes of CFCs.
- 7. Gases in the atmosphere Human activities have increased the contribution Production of carbon dioxide Destruction of ozone layer increased the level of UV-B radiations Production of green house gases
- 8. Buy energy efficient appliances Reduce private transport Bike or walk if you are going somewhere local Use energy saving consumers Switch to energy efficient light bulbs
- 10. Biological warfare is Use of any living organism Any toxins to cause disease or death State sanctioned Chemical warfare is Use of non-living products Produced by living organism
- 11. The Assyrians 6Th Century BC. The British Army (1763–66). German government during World War I (1914–1918) World War II (1939–1945)
- 12. On Environment Soil erosion Loss of vegetation Specie degradation On Humans Cancer Birth defects
- 13. The developed treatment is not defensive No effective treatment against poisons Government should made efforts.
- 15. Definition:- Rainfall that has been acidified with the oxides of sulfur and nitrogen is called acid rain . The ph of this rain is less than 5.6. this precipitation may also be in the form of snow, fog and hail. Formation of acid rain:- SO2 and NOx reacts with water in atmosphere to form sulfuric acid and nitric acid, then they come down with the rain and harm the earth. Chemical reaction:- NOx + H2O --------> nitric acid (HNO3) SO2 + H2O --------> sulfuric acid (H2SO4) Acid rain is a broader concept refrying to two types of depositions:- 1- Wet deposition: acids can fall to the ground in the form of rain, snow, fog, or mist. 2- Dry deposition: acid chemicals may become incorporated into dust or smoke and fall to the ground. Definition:- Rainfall that has been acidified with the oxides of sulfur and nitrogen is called acid rain . The ph of this rain is less than 5.6. this precipitation may also be in the form of snow, fog and hail. Formation of acid rain:- SO2 and NOx reacts with water in atmosphere to form sulfuric acid and nitric acid, then they come down with the rain and harm the earth. Chemical reaction:- NOx + H2O --------> nitric acid (HNO3) SO2 + H2O --------> sulfuric acid (H2SO4) Acid rain is a broader concept refrying to two types of depositions:- 1- Wet deposition: acids can fall to the ground in the form of rain, snow, fog, or mist. 2- Dry deposition: acid chemicals may become incorporated into dust or smoke and fall to the ground.
- 16. There are two sources of acid rain:- 1- Natural sources:- Emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) from swamps. volcanoes. decaying vegetation. 2- Man-made sources:- fossil fuel combustion in factories. Diesel and gas combustion in vehicles. Home fires gives off smoke. Causes of acid rain:- Acid rain is mainly caused by the substances that are being released into the air such as:- Carbon dioxide Carbon monoxide Chlorofluorocarbons
- 17. Lead. Nitrogen oxides. Ozone. Particulate matter. Sulfur oxides. Volatile organic compounds. (voc’s) These substances are emitted by factories and power plants that burn fuels such as natural gas, coal or oil. Another source is vehicles that burn gasoline and diesel. Others are mining , artificial refrigeration, heavy industries, fertilizers, Pesticides, paints, road construction. All these activities are the main cause of acid rain. Lead. Nitrogen oxides. Ozone. Particulate matter. Sulfur oxides. Volatile organic compounds. (voc’s) These substances are emitted by factories and power plants that burn fuels such as natural gas, coal or oil. Another source is vehicles that burn gasoline and diesel. Others are mining , artificial refrigeration, heavy industries, fertilizers, Pesticides, paints, road construction. All these activities are the main cause of acid rain.
- 19. Effect on sea life. Effects on plants. Effect on human and other leaving beings. Effect on non-living things. Areas of world effected by acid rain are:- North eastern section of united state. Central Europe (Sweden, Norway & Finland) Asian countries India & china because of large number of factories.
- 20. Use fuels that burn more cleanly. Burn coal more efficiently. Factory chimneys can be fitted with scrubbers that releases 90-95% sulfur free smoke. Forcing emission standards on vehicles that burn gas and diesel. Catalytic converter into car exhaust pipes to minimize the amount of sulfur dioxide in car exhaust.
- 22. Global warming is the increase of Earth’s average surface temperature due to effect of greenhouse gases, such as carbon dioxide, methane and nitrous oxide etc.
- 23. Greenhouse gases are the gases in the earth’s atmosphere that collect heat and light from the sun. With too many greenhouse gases in the air, the earth atmosphere will trap too much heat and the earth will get too hot.
- 24. Global warming cause: Carbon dioxide emission from fossil fuel burning power plants. Carbon dioxide emission from burning gasoline for transportation. Methane emission form animals, agriculture. such as rice paddies. Deforestation for wood pulp and farmlands.
- 25. Global warming effect: Rise in sea level worldwide. More killer storms. Massive crop failure. Wild spread extinction of species. Disappearance of coral reefs.
- 26. Reduce, reuse and recycle of usable product. Use less heat and air conditioning. Change a light bulb with compact fluorescent light bulbs. Drive less and drive smart. Use less hot water. Use the off switch. Plant a tree.