有关pollution的演讲.doc

PollutionGood morning, everyone! My topic is pollution .This topic is very common to most of us .Because the topic of pollution becomes hotter and hotter nowadays.With a development of high speed in industry and the increase of the world population in recent years, the pollution has become one of the greatest threaten to human beings. China, one of the biggest developing countries in the world, are facing austere situation of environment pollution. In the past decades of years, we sacrifice the environment to develop the economy. The ignorance of environment pollution shows that environment weighs quite light compared with the economy, sports, politics, etc. Now we are facing the worsening problem of pollution. We are all well aware of the terrible situation: water loss and soil erosion along the Changjiang River and Huanghe River, the gray and cloudy sky on the industrial city, the dead water without living things, and the greenhouse effect. Although propaganda and education began emphasize the problem these days, there is still a long way to go. Because we have formed fixed concepts on the environment issues for a long time. Many specific laws about environment are either blank or unclear. Many activities and behaviors that do harm to the environment can go without punishment. For instance, many companies along the Changjiang River discharge large volumes of waste water into the river, but they can easily avoid punishment by stopping discharging when the departments of environment discovered it. And sadly the environment department can do little to this.In conclusion, it is obvious that pollution is a complex problem in China and the causes of it are really versatile. In addition, all these factors are not isolated and always interactive with each other. So the solution to this problem should be based on a comprehensive and deep understanding of it. At last I just want to say: our human beings should aware of the current austere situation of the environment pollution and try to do something to improve it. No matter for ourselves, or for our offspring.Thank you for your attention!Global warming is an increase in the earths temperature due to fuels, industry, and agricultural processes caused by human, natural, and other gas emissions. This results in an increased emission of greenhouse gases. Short-wave solar radiation sinks into the Earths atmosphere and warms its surface; while long wave infrared radiation emitted by earths surface is absorbed, and then re-emitted by trace gases. Climate changes occur in our earths atmosphere due to a buildup of greenhouse gases. Greenhouse gases can occur naturally as well as a result of human activities. Problems can occur when higher concentrations of greenhouse gases are present in our atmosphere because they have enhanced our earths heat trapping capability. There are many misconceptions about global warming. Some believe that pollution causes global warming, but the fact is global warming is the result of burning fossil fuels, coal, and oil that release carbon dioxide. Another misconception is nuclear power causes climate change. Nuclear power actually reduces emissions of carbon dioxide when used in place of coal. Some believe that global warming means that it will become warmer all over. The name is misleading because in some places, it will actually become colder. The majority of scientists believe global warming is a process underway and that it is human-induced. The greenhouse gases are carbon dioxide, methane, and nitrous oxide. These gases occur naturally. The Earth uses those gases to warm its surface. Carbon dioxide is released into the atmosphere when solid waste, fossil fuels, wood, and wood products are burned. Each greenhouse gas absorbs heat differently. If natural gases did not occur, the temperatures would be 91.4 degrees cooler than the current temperatures. These gases trap heat and cause the greenhouse effect, rising global temperatures. Human activities add to the levels of these gasses, causing more problems. The burning of solid waste, fossil fuels, and wood products are major causes. Automobiles, heat from homes and businesses, and factories are responsible for about 80% of todays carbon dioxide emissions, 25% of methane, and 20% of the nitrous oxide emissions. The increase in agriculture, deforestation, landfills, industrial production, and mining contribute a significant share of emissions too. The gases released into the atmosphere are tracked by emission inventories. An emission inventory counts the amount of air pollutants discharged into the atmosphere. These emission inventories are used by many organizations. Global warming is a danger to a humans health. Its affect on climate can adversely affect humans. Plagues have been attributed to global warming. An increase in temperature can result in a longer life cycle for diseases or the agents spreading them. Living in a warm area makes egg production a quicker process. Global warming will lead to more precipitation, which enables infectious diseases to be more easily contracted and spread. Effects of global warming on human health might not be immediately detected. Global warming can affect our future ability to obtain food. As climates change, plants and animals will change, leading to a change in the eating patterns of humans. An increase in precipitation is one result of global warming that could have devastating effects. First, the quality of crops would be affected by an increase in precipitation. Second, increasing rain could lead to an increase in soil erosion. There are ways that you can help prevent global warming. Car pooling, auditing the energy in your home, buying fuel-efficient cars, and reducing the electricity in your home are ways to help prevent global warming. You can also write to your local congress representative or your local newspaper in response to stories, which say global warming, does not exist. Government authorities