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Environmental scientists are worried about the green house effect, which has been noticed throughout the world. The green house effect is actually, a gradual warming up of the earth, which can disturb its natural environment. The main cause of this effect is the large scale industrialization, in almost all the countries of the world. The gases released by the factories and power-driven vehicles, have made the Earth's protective cover weak. Large scale felling of trees, has made the problem more acute.