Scientists say that something very serious is happening to the earth. It will begin to get 56 in the following years. There will be major changes in ____57_ in the new century. Coastal waters will have a ___58_temperature.This will have a __59__effct on agriculture. In northen areas,the ___60_season will be ten days longer by the year 2010.However,in warmer areas,it will be too dry.The _61__of watcr could___62_by cighty pereent. This would _63___a large decrease in agriculture production.
World temperature could___64__ two degrees centigrade by the year 2040.However,the increase could be three times as great in the Arctic and Antarctic areas.This could cause the _65__shects to melt and raise the __66__ of the oceans __67__ one to two meters.Many coastal cities would be __68__ water.
Why is this happeningThere is to __69__ carbon dioxidc in the air.__70__ oil,gas and coal burn,they creatc large amounts of carbon dioxide.This carbon dioxide lets __71__ enter the earth’s atmosphere and __72__ the earth.However,it doesn’t let as much heat __73__ the atmosphere and enter space.It’s like a blanket.The heat __74__ the sun can pass through the blanket to warm the earth. The heat __75__ there and can’t escape through the blanket again.
Scientists call this the green-house effcct.