高级英语第一册第六课PPT

Ozone depletion
A layer of ozone in the stratosphere prevents most ultrviolet and other high-energy radiation,which is harnful to life,from penetrating to the earth's surface.Some environmental scientists fear that certain man-made pollutants,eg.nitric oxide,CFCs,etc.,may interfere with the delicate balance of reactions that maintains the ozone's concentration,possibly leading to a drastic depletion of stratosphere ozone.This is now happening in the stratosphere above the Polar Regions.
Words and phrases
• bow • the foward end or part of a boat or ship 船头 • a weapons for shooting arrows ,consisting of an arch of flexible wood ,plastic ,metal ,etc.bent by a string 弓 • a knot tied with too loose ends 蝴蝶结 • dune • a mound or ridge of drifted sand ,occurring near the sea coast and in a desert 沙丘 • divert • to turn (a person or thing )aside from a course ,direction or etc,deflect使转向，使绕道；Southbound traffic will have to be diverted onto minor roads.南行车辆将不得不 饶次要道路而行。 • to distract the attention of 转移某人的注意力，使分心 The beautiful music diverted his drawing.美妙的音乐转移 了他的注意力
• •
The introduction of the text
• Ships in the Desert • “沙漠之舟”是一个非常引人 注目的题目，船停泊在沙漠中 时很少见过的景象，因此能够 有效地唤起读者的好奇心和探 究的兴趣。 • 作者通过广泛的例证，鲜明的 对比，巨大的反差，生动的类 比，明确的分析等向读者提供 了大量的考察信息，探究了全 球变暖的原因，追溯了让人类 与环境的关系发展与变化，提 出了遏制气候变暖的基本方法。
Some typical examples
wk.baidu.com
soil erosion
• The area of the soil erosion has topped 1.5～1.6 million square kilometer • Making eroded soil decrease by 5 billion tons every year • The area of soil erosion takes up 1/12 of the world's total(600 billion tons) • It is equivalent to destory cultivated land 1,000,000 mu • The area of the soil erosion accounts for 80%～90% of the total land area of our country
The Aral Sea
1, located in Uzbekistan and Kazakhstan is historically a saline lake . 2, It is in the centre of a large ,flat desert basin. The Aral Sea is a prime example of a dynamic environment. 3, In 1960 the world’s fourth largest lake, the size of the entirety of Southern California.
America's Great Lakes
• America's Great Lakes refer to the group of five freshwater lakes,central North America,between the United States and Canada,largest body of fresh water in the world.From west to east,they are Lake Superior,Lake Michigan,Lake Huron,Lake Erie and Lake Ontario. HOMES can help remember the names of the five lakes,H stands for Huron,O for Ontario,M for Michigan,E for Erie and S for Superior.
密歇根湖 苏必利尔湖
伊顿湖
休伦湖
安大略湖
The Structure of This text
• This text can be divided into three parts • Part I(para 1) The pullution caused great environmental damage. • PartⅡ(Para2 to 25)The author analyzed the pollution problem from different aspects • PartsⅢ(Para 26) In order to solve the environment problem,a lot of advice was given,but the author thought the key was to change people's attitude towards the relationship of man and environment.
species extinction
• There are 75 species becoming extinct every day.and three species extinct every hour in the world. • U.S well-known biologist Stuart Pimm in Duck University believes that if such a rate continues,by 2050,the current quarter or the hall of the species will be extinct or endangered.
Lesson 3 Ships in the Desert
Al Gore
Content
• Introduction about the author • Some typical examples of ecological destruction • Global warming • The introduction of the text • Words and phrases • Something necessary we can do to protect global environment
• • • • • • Climate change Effects of global warming are causing the temperature of the Earth to slowly rise, causing massive global changes to our natural environment. Rising sea level Effects of global warming are rapidly melting glaciers around the globe, causing a rising sea level and possibly coastal flooding and other weather problems in the future. Ecosystem changes Effects of global warming are changing certain ecosystems throughout due to temperature fluctuations. Animals and plants are being forced to adapt to this, and as a result are dying off. Breakdown of the Ozone layer Effects of global warming are creating holes in the ozone layer, primarily from human use of products that emit toxic chemicals. The ozone layer absorbs UV radiation from the sun, the holes are causing amounts of toxic chemicals present in our breathing air to increase at a rapid rate.
The cause of global warming
.
The 20th century has had a population explosion Air pollution caused by cars environmental problems
The effects of global warming
Al Gore
Al Gore was born in 1948 in Washington D.C., U.S. He has been a Senato(1984-1992) representing the State of Tennessee, and U.S.Vice-President (1992-2000) under President Bill Clinton. He ran for the Presidency against George W. Bush jr. but the latter won the closely tied election and has become the 43rd American President. After retirement, he devoted his time to environmental protection.The text is taken from Al Gore’s book Earth in the Balance
Global warming
Global warming has become perhaps the most complicated issue facing world leaders. On the one hand, warnings from the scientific community are becoming louder, as an increasing body of science points to rising dangers from the ongoing buildup of human-related greenhouse gases — produced mainly by the burning of fossil fuels and forests. On the other, the technological, economic and political issues that have to be resolved before a concerted worldwide effort to reduce emissions can begin have gotten no simpler, particularly in the face of a global economic slow down