译林版（2020）必修第三册Unit 2 Natural disasters Welcome to the unit & Reading 课件(共22张PPT)

(共22张PPT)
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 the atmosphere that consists of strong winds and low pressure. The winds rotate clockwise in the southern hemisphere and counter clockwise in the northern hemisphere. A hurricanes is usually characterized by a low-pressure center with strong winds and spiral rain bands.
A sandstorm is also known as the dust storm, which is a strong wind that blows across the arid and semi-arid regions. It causes soil erosion and it occurs due to the poor management of dry land and over-grazing (过度放牧）of vegetation（植被）.
An ice storm is a form of winter storm wherein cold and freezing rain is experienced. Ice storm is a natural disaster, which can cause damages and health hazards to mankind and livestock.
Fast reading
Read for the structure.
How is a news report usually organized
Inverted pyramid.
Inverted pyramid
The tail
(optional)
The lead
The body
the most important information
detailed information
background or supporting information
Reading for structure
News report 1 News report 2
The lead
The body
The tail
Para. 1: FALMONT—On 17 March, 476 students and 36 teachers at Falmont Primary School escaped an earthquake that hit the county at 2:27 p.m.
Para.1: A 10-year-old girl, Sabrina Andron, helped around 100 people escape danger with her knowledge of tsunamis.
Paras. 2 and 3: The process of escaping successfully from the earthquake.
Paras. 2 and 3: How Sabrina saved so many lives.
Para. 4: The reason for their calmness in the earthquake.
(Not mentioned.)
17 March
themselves from an earthquake
saved
The school’s safety procedures taught students and teachers how
to protect themselves
Goldshore Beach
saved around 100 people
on the beach from a terrible tsunami
The girl warned of an approaching
tsunami, and the beach was cleared just in time
Detailed reading
Read the news reports and complete the table below.
1. Why do the natural disasters break out more often
2. What can we do to reduce the possibility of natural disasters such as fire
3. What do you think of the first sentence — natural disasters are terrible reminders of the power of nature
4. Are natural disasters closely connected with man-made disasters Can you give an example
Write down a short paragraph describing a natural disaster. Your writing should include an example and an ending about what we should do.