人教版（2019）高中英语必修第一册 Unit 4 Natural Disasters video Time 课件（共16张PPT）
文档属性
| 名称 | 人教版（2019）高中英语必修第一册 Unit 4 Natural Disasters video Time 课件（共16张PPT） |  | |
| 格式 | ppt | ||
| 文件大小 | 7.5MB | ||
| 资源类型 | 教案 | ||
| 版本资源 | 人教版（2019） | ||
| 科目 | 英语 | ||
| 更新时间 | 2021-01-11 21:20:15 | ||
图片预览
文档简介
Video Time
Natural Disasters
What is happening in the pictures?
Tsunami
What is a tsunami?
What causes a tsunami?
What is its damage?
How can we prevent it form becoming a disaster?
海啸，是由海底地震、火山爆发、海底滑坡或气象变化所产生的破坏性海浪，海啸的波速高达每小时700~800千米，在几小时内就能横过大洋;波长可达数百公里，可以传播几千公里而能量损失很小。
海啸是一种灾难性的海浪，通常由震源在海底下50千米以内、里氏震级6.5以上的海底地震引起。水下或沿岸山崩或火山爆发也可能引起海啸。在一次震动之后，震荡波在海面上以不断扩大的圆圈，传播到很远的距离，正象卵石掉进浅池里产生的波一样。海啸波长比海洋的最大深度还要大，轨道运动在海底附近也没受多大阻滞，不管海洋深度如何，波都可以传播过去。
海啸发生时，震荡波在海面上以不断扩大的圆圈，传播到很远的地方。它以每小时600-1000公里的高速，在毫无阻拦的洋面上驰聘1万-2万公里的路程，掀起10-40米高的拍岸巨浪，吞没所波及的一切，有时最先到达的海岸的海啸可能是波谷，水位下落，暴露出浅滩海底;几分钟后波峰到来，一退一进，造成毁灭性的破坏。
剧烈震动之后不久，巨浪呼啸，以摧枯拉朽之势，越过海岸线，越过田野，迅猛地袭击着岸边的城市和村庄，瞬时人们都消失在巨浪中。港口所有设施，被震塌的建筑物，在狂涛的洗劫下，被席卷一空。事后，海滩上一片狼藉，到处是残木破板和人畜尸体。
海啸预警
Video Time
Tsunami: Killer Wave
Tsunami waves can strike out of nowhere and cause a lot of destruction. Scientists study and track tsunamis in order to warn people and minimise deaths.
C
A
B
√
√
√
After You Watch
Work in pairs. Discuss the questions
1. What have you learnt about tsunamis?
2. What kind of help do you think people who have suffered from a tsunami need?
1. What have you learnt about tsunamis?
I have learnt that they are dangerous./
...that they aren't noticeable or strong
until they hit the coast./
...that they cause more damage when
they recede./
2. What kind of help do you think people who have suffered from a tsunami need?
They need food, water, shelter, etc. They may also need medical help and emotional help if they have lost loved ones.
长岭县第三中学
Thank you for your listening
Natural Disasters
What is happening in the pictures?
Tsunami
What is a tsunami?
What causes a tsunami?
What is its damage?
How can we prevent it form becoming a disaster?
海啸，是由海底地震、火山爆发、海底滑坡或气象变化所产生的破坏性海浪，海啸的波速高达每小时700~800千米，在几小时内就能横过大洋;波长可达数百公里，可以传播几千公里而能量损失很小。
海啸是一种灾难性的海浪，通常由震源在海底下50千米以内、里氏震级6.5以上的海底地震引起。水下或沿岸山崩或火山爆发也可能引起海啸。在一次震动之后，震荡波在海面上以不断扩大的圆圈，传播到很远的距离，正象卵石掉进浅池里产生的波一样。海啸波长比海洋的最大深度还要大，轨道运动在海底附近也没受多大阻滞，不管海洋深度如何，波都可以传播过去。
海啸发生时，震荡波在海面上以不断扩大的圆圈，传播到很远的地方。它以每小时600-1000公里的高速，在毫无阻拦的洋面上驰聘1万-2万公里的路程，掀起10-40米高的拍岸巨浪，吞没所波及的一切，有时最先到达的海岸的海啸可能是波谷，水位下落，暴露出浅滩海底;几分钟后波峰到来，一退一进，造成毁灭性的破坏。
剧烈震动之后不久，巨浪呼啸，以摧枯拉朽之势，越过海岸线，越过田野，迅猛地袭击着岸边的城市和村庄，瞬时人们都消失在巨浪中。港口所有设施，被震塌的建筑物，在狂涛的洗劫下，被席卷一空。事后，海滩上一片狼藉，到处是残木破板和人畜尸体。
海啸预警
Video Time
Tsunami: Killer Wave
Tsunami waves can strike out of nowhere and cause a lot of destruction. Scientists study and track tsunamis in order to warn people and minimise deaths.
C
A
B
√
√
√
After You Watch
Work in pairs. Discuss the questions
1. What have you learnt about tsunamis?
2. What kind of help do you think people who have suffered from a tsunami need?
1. What have you learnt about tsunamis?
I have learnt that they are dangerous./
...that they aren't noticeable or strong
until they hit the coast./
...that they cause more damage when
they recede./
2. What kind of help do you think people who have suffered from a tsunami need?
They need food, water, shelter, etc. They may also need medical help and emotional help if they have lost loved ones.
长岭县第三中学
Thank you for your listening