北师大版高中英语选修八unit22environmentalprotectionthetwelfthperiod教案

北师大版高中英语选修八unit22environmentalprotectionthetwelfthperiod教案内容摘要：

y underway are unlike anything that has been seen before. Record levels of carbon dioxide are having a far reaching change over our weather, sea levels, and climate. 2. How can Global Warming affect our lives? Answer: Global warming is sometimes referred to as the most dangerous experiment ever conceived. We do not know what the full affect of radical climate change will be on our environment, but we do know that even a modest rise of 2176。 3176。 F (176。 176。 C) could have dramatic effects. In the last 10,000 years, the Earth39。 s average temperature hasn39。 t varied by more than 176。 F (176。 C). Temperatures only 5176。 9176。 F cooler than those today prevailed at the end of the last Ice Age, in which the Northeast United States was covered by more than 3,000 feet of ice. Leading scientists assert that a rise of 3 degrees would cause famine and drought and threaten millions of lives. It would also cause a worldwide drop in crops of between 20 and 400 million tons, threatening 400 million more people with famine, and put up to 3 billion people at risk of flooding and without access to fresh water supplies. Few ecosystems could adapt to such a dramatic temperature change, resulting in the destruction of half the world39。 s nature reserves and a fifth of coastal wetlands. Global sea levels could rise by more than 20 feet if the ice shelves in Greenland and Antarctica collapsed, which is a distinct possibility if temperatures continue to climb. Droughts and wildfires will occur more often. More than a million species worldwide could be driven to extinction by 2050. 3. Does the rise in the earth’s temperature cause more intense storms /hurricanes/ tornados here in the US? If so, how? Answer: While it is impossible to blame any single event on global warming, there are several reasons to believe that global warming will create more intense storms. Hurricanes are powered by warm water on the surface of the ocean. As global warming heats the surface of the water, hurricanes will increase in speed, power, and frequency. Tornadoes are caused by rapidly rising amounts of heat from the lower areas of the atmosphere to higher portions of the sky. While scientists are again reluctant to pin individual storms on global warming, global warming does create greater amounts of heat in the lower portions of the atmosphere, creating more tornadocausing energy to be released into the upper atmosphere. 4. What are the largest sources of global warming pollution in the world and in the United States? Answer: The US produces far more carbon dioxide than any other country in the world. According to the latest figures by the Department of Energy, the US produces 22% of all CO2 emitted into the atmosphere, at 5, million metric tons in 2020. That is more than China, and India together (17% and % respectively), more than Russia (6%), Japan (%), Australia (%) and the whole of Europe put together (%). In the United States, the major sources of CO2 emissions stem from burning fossil fuels, like coal, natural gas, and oil. We burn coal and natural gas to produce electricity and energy for our homes, businesses, and factories, while most of the oil is burned to power transportation, planes, buses, and especially cars. However, all of the technology that produces this energy is outdated and inefficient. We can continue to live our lives by putting more efficient technology to use, and by getting more energy from clean sources, like wind and solar. 5. Can we curb our emissions of global warming pollution without hurting our economy? Answer: Absolutely. In addition to being dirty and dangerous, America’s coal and nuclear power plants are wildly expensive, America39。 s energy policy is terribly expensive, requiring large subsidies while taking a heavytoll (造成重大损失 ) on consumers. There have been dozens of studies which show that by investing in clean energy, such as ren。