[实用参考]全球变暖-(英文).ppt

• So,let us do our best to solve this problem,or we will bear this problem in the future
Droughts
If the earth's average temperature 4 degrees Celsius, the world will have more than 30 million people water shortages. 如果地球平均气温上升4摄氏度，全 球就会有30多亿人面临缺水问题。
Melting glaciers
• the earth‘s poles island fate snow melt can lead to rising sea levels, many islands will be drowned, some island may not exist.
• 地球两极冰雪融化会导致海平面上升，众多 岛屿将被淹没，一些岛国可能不复存在。
What is Global Warming?
• Global warming is the observed centuryscale rise in the average temperature of Earth's climate system.
• 全球变暖是指全球气温在近一百年来不断上 升，呈现变暖的趋势，这样一种气候变化特 征。
warming
Negative effects
Positive effects
1.Cause the sea level to rise
1.make plants grow faster
2.Melting glaciers 3.Droughts
2.crops will produce more
4.Disappearance of species
Human activities
1.Industrial waste gases 2.Deforestation 3.Traffic jam
Industrial waste gases
Deforestition
Traffic jam
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What're the effects of global
The cause of global warming
1.Natural cause: The green house effect
2.Human reasons: Human activities
The green house effect
The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases. 温室效应是一个过程,从行星表面热辐射被大气吸收温 室气体,并再次辐射向四面八方。因为这部分再辐射回 到地表和低层大气,它导致海拔平均表面温度高于没有 这部分气体。