The 600-word history paper is related to Gao Changgong.

In recent years, people feel that the weather has suddenly become hot. The original cool autumn almost didn't start until the end of 10, and the hottest day in August actually reached more than 40 degrees. Why is this? It turned out to be human's own fault.

With the rapid development of human high technology, the side effects of science are gradually reflected, and global warming is an example. The weather is hot, and soaking in air conditioning in the heat has become a new "hobby", but have people ever thought about the negative effects of air conditioning? Of course, the answer is yes. The gas discharged from air conditioners contains a lot of methane, which is also a gas that causes global warming. At the same time, air conditioning will waste a lot of electricity, so try to avoid using air conditioning.

And another reason is: carbon dioxide! Automobile exhaust and factory exhaust contain a lot of carbon dioxide, which is the most likely to cause greenhouse effect (that is, global warming). There are more and more cars now. According to statistics, by 2 1 century, there will be 700 million cars in the world, and a large amount of exhaust gas will seriously affect us, such as cough and pharyngitis ... The most important thing is global warming. Statistics show that the per capita carbon dioxide emissions in the United States have reached 20 tons a year! China's annual per capita carbon dioxide emissions are also 2.5 1 ton a year! The environment around us is undergoing serious changes.

The more important reasons are: sharp decline of forests, destruction of water resources, serious destruction of ecological chain, barren land and serious water pollution. According to statistics, 65,438+00% of the rivers in the world are polluted, and the supply of fresh water has become a problem. At the same time, due to the extensive use of minerals, the burning CO2 gas caused air pollution, and the ozone layer was severely damaged, and ozone holes appeared in the north and south poles, which aggravated the environmental deterioration. This vicious circle will eventually lead to a serious impact on people's lives.

What kind of tragedy is this? Of course it is obvious! The weather is getting hotter, the sea level is rising, the glaciers in the North and South poles are melting, and coastal cities and island countries are flooded. All these have seriously affected the survival of mankind. Experiments show that the sea level will rise by more than half a meter in the next 300 years, which is still the most optimistic data. In another seven years, global warming will continue irreversibly. What is even more frightening is that due to the melting of the Arctic ice, rainfall has increased, and a large amount of fresh water has flowed into the North Atlantic, destroying the Mexican warm current. Once the Mexican warm current is cut off, the temperature in northwest Europe will drop by as much as 5-8 degrees, which will probably lead to a new ice age! I'm sure you've seen the film The Day After Tomorrow. The scene in the play is a true portrayal of our planet hundreds of years later: tornado, ice crack, sudden drop of temperature, ice storm, freezing rain, earthquake, flood, tsunami ... This is not a crazy fantasy, but it will become a reality if human beings don't stop destroying the environment! Global warming is not only hot weather, but also many negative effects!