上海崇明中学—“绿色校园，绿色家园”3R系列活动

What is meant by the term,the greenhouse effect,is that the heat from the sun comes into the Earth's atmosphere and cannot get out,so it becomes trapped.It gets its name because this is very much like a greenhouse.This effect occurs as the incomingshort wave radiation is changed when it hits the Earth's surface into long wave or infrared radiation.Heat energy in this form is then absorbed and stored in water vapor and carbon dioxide in the atmosphere.

Many different things cause the greenhouse effect. The amount of carbon dioxide in the atmosphere is increased by 0.4 percent each year because of the massive consumption of dossil fuels such as oil,coal,and natural gas.Another contributing factor is the amountof forest logged.Every second of the day the area of a football field in trees is cleared by either being logged or bunt.Two other deadly greenhouse gases that are entering the atmosphere even faster than carbon dioxide are methane and chlorofluorocarbons,although they are not as damaging in the long run .

These increases are likely to affect worldwide temperatures dramatically.In 100 years the average temperature for most parts of the world will increase from between 2℃ to 6℃ if greenhouse pollution continues at its present rate. This temperature increase would drastically affect the growth of many different crops and cause the polar ice caps to melt ,thus increasing sea levels by several metres. If this rise in sea level were to occur,many areas would be much more prone to flooding,and generally much deeper floods than would be expected nowadays.This flooding would be happen pparticularly around coastal regions worldwide,and also along many rivers that flow or from coastal inlets.

The greenhouse effect cannot be neglected because it leads to rising water levels and temperatures that can have a serious effect on the world's climate.Changes in the climate can lead to significant changes in agricultural industries.This can lead to goog farmland becoming deserts,make it too hot for some crops to grow.For these reasons ,it is important to carefully manage the greenhouse effect by reducing the amount of carbon dioxide going into air and planting more trees.