Global warming is the increase in the average temperature of the Earth's near-surface air and oceans since the mid-20th century and its projected continuation. The Intergovernmental Panel on Climate Change (IPCC) concludes that increasing greenhouse gas concentrations resulting from human activity such as fossil fuel burning and factories. Carbon dioxide is not the only gas released by human activities that can cause warming. Human emissions of methane and nitrous oxide together contribute almost half as much warming. The main cause of the hole in the ozone layer is chlorofluorocarbons (CFCs), gases that are used in refrigerators, air conditioners, and industrial applications. While CFCs alone cause warming, their ozone destruction can cause cooling. So far these warming and cooling influences have approximately balanced.Effect of global WarmingEl Niño-Southern Oscillation is a periodic change in the atmosphere and ocean of the tropical Pacific region. It is defined in the atmosphere by changes in the pressure difference between Tahiti and Darwin, Australia, and in the ocean by warming or cooling of surface waters of the tropical central and eastern Pacific Ocean. El Niño is the name given to its warm phase of the oscillation -- the period when water in that region is warmer than average. La Niña is the name given to the cold phase of the oscillation, or the period when the water in the tropical Eastern Pacific is colder than average. The oscillation has no well-defined period, but instead occurs every three to eight years. Mechanisms that sustain the El Niño-La Niña cycle remain a matter of research. The El Niño-Southern Oscillation is often is abbreviated in scientific jargon as ENSO and in popular usage is commonly called simply El Niño. The name is Spanish for "the boy" and refers to the Christ child, because periodic warming in the Pacific near South America is usually noticed around Christmas. Conversely the name for the cool phase of the oscillation, "La Niña," is Spanish for "the girl." El Niño is associated with floods, droughts and is linked to other weather disturbances in many locations around the world. El Niño's effects in the Atlantic Ocean lag behind those in the Pacific by 12 to 18 months. Developing countries dependent upon agricultural and fishing are especially affected. El Niño's effects on weather vary with each event. Recent research suggests that treating ocean warming in the eastern tropical Pacific separately from that in the central tropical Pacific may help explain some of these variations. Climate scientists define El Niño and La Niña based on sustained differences in Pacific-Ocean surface temperatures when compared with the average value. The accepted difference is anything greater than 0.5C (or 0.9F) averaged over the east-central tropical Pacific Ocean. When this happens for less than five months, it is classified as El Niño or La Niña conditions; if the anomaly persists for five months or longer, it is called an El Niño or La Niña "episode." Typically, this happens at irregular intervals of 2–7 years and lasts nine months to two years. The first signs of an El Niño are: 1. Rise in surface pressure over the Indian Ocean, Indonesia, and Australia 2. Fall in air pressure over Tahiti and the rest of the central and eastern Pacific Ocean 3. Trade winds in the south Pacific weaken or head east 4. Warm air rises near Peru, causing rain in the northern Peruvian deserts 5. Warm water spreads from the west Pacific and the Indian Ocean to the east Pacific. It takes the rain with it, causing extensive drought in the western Pacific and rainfall in the normally dry eastern Pacific. El Niño's warm current of nutrient-poor tropical water, heated by its eastward passage in the Equatorial Current, replaces the cold, nutrient-rich surface water of the Humboldt Current. When El Niño conditions last for many months, extensive ocean warming occurs and its economic impact to local fishing for an international market can be serious. we can save the world 1.Turn off all electric equipments such as television, computer, stereo when you are not using them, can reduce carbon dioxide 1,000 pound per year. 2. Change your ordinary light bulb to the Compact Fluorescent Light bulb (CFL) which can save more energy than the ordinary light bulb. Energy-saving bulbs last on average 12 times longer than the ordinary light bulbs, with a life span of around six years. 3. Using LED light bulb can save your money upto 40% as well as you can save 150 pounds of carbon emissions per year. 4. Join or start a community group in the neighborhood and dedicate a day to planting trees throughout the community. Trees store carbon and provide shade during the summer, which can cool houses and result in lower energy use. Encourage the use of bikes with bike rack placement at public buildings and businesses to promote biking over driving. By doing these you can reduce carbon dioxide 20 pound. 5. Protect the earth from global warming by controlling the driving speed not more than 90 km/h. It can save fuel 20% and can reduce the carbon dioxide 1 ton per car. 6. Put the pressure in your tyres not too less can save fuel 3%. 7. Dry your clothes by sun light instead of drier machine to save the energy. 8.Design the accommodation to use more natural sun instead of using light bulb. 9. Reduce using plastic bags. They are typically made of polyethylene and can take up to 1,000 years to biodegrade in landfills that emit harmful greenhouse gases.10. Use piece of paper both sides because each piece of paper has utilized fuel and electric energy.
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