(
课件网) Unit 2 Natural disasters Nature is kind of a loving mother, but also a butcher in cold blood. -- Victor Hugo Natural disasters are extreme, sudden events caused by environmental factors that injure people and damage property. What are natural disasters Top 10 Natural Disasters 1. hurricane 2. earthquake 3. tornado 4. volcanic eruption 5. tsunami 6. flood 7. wildfire 8. drought 10. landslide 9. avalanche/snow slide Natural disasters are terrible reminders of the power of nature. Watch the video and finish the following exercises. Plates moving underground can cause an earthquake, which is _____ of the earth’s surface. When a volcano erupts, _____, volcanic ash and even rocks escape through a large opening at the top. A large amount of _____ falling down a hill or mountain is called a landslide. a sudden shaking hot gases earth and rock Discuss the following questions. 1. What other types of natural disasters do you know about 2. What natural disasters in history have you heard about Natural disasters locust Plague蝗灾 tsunami tornado drought sandstorm typhoon forest fire flood and more … Earthquake An earthquake is a sudden shaking of the earth's surface, caused by the movement of plates underground. Earthquakes are most common where plates meet. Several million small earthquakes happen every year, but most do not cause any damage. Serious earthquakes, however, can destroy entire cities. When a terrible earthquake hit Tangshan in 1976, about 240 thousand people died and over 160 thousand people were badly injured, almost the whole city was destroyed. Volcanic eruption A volcanic eruption occurs when hot gases, volcanic ash and even rocks escape through a large opening at the top of a volcano. The gases and ash can cause acid rain and even storms. The hot liquid rock moving down the volcano burns everything and anything in its way. The eruption of Mount St Helens in 1980 was the worst volcanic disaster in the history of the United States. It killed 57 people and about 7,000 large animals. Landslide A landslide happens when a large amount of earth and rock falls down a hill or mountain. Landslides are often caused by heavy rainfall, earthquakes, volcanic eruptions or other natural disasters. Sometimes they are also caused by human activities such as cutting down forests. Serious landslides can cause whole mountainsides to roll away. Villages or towns located in the path of such landslides can be completely destroyed. In 2014, a landslide in India killed at least 150 people. other types of natural disasters Extreme temperatures caused by a heat wave or cold wave are one of many climatological hazards（危险）. A heat wave increases the temperature in a certain region and pushes the human body beyond its limit. The same is the case with a cold wave that is accompanied with heavy snowfall and extreme cold, which may lead to hypothermia. Hurricanes refer to a closed circulation system in ... ...
