Now global warming has become a threat to all living beings. It is for greenhouse effect. It is the gradual warming of the air because of heat being trapped on the earth. It is happening for environmental pollution. We are destroying our forests, growing industries and mills and factories, using CFC gas. Thus, we are polluting our environment. By the destruction and burning down our forests, the amounts of carbon dioxide are increasing. The increased amounts of carbon dioxide around the earth have made a layer in space. The sun rays are coming through the layer but the heat cannot pass through it. So the heat is being trapped on the earth and making our globe warmer. Thus, the temperature of the world is increasing day by day. The weather pattern is changing. The alarming news is that the polar ice caps are melting. This might cause the flooding of huge areas of the globe. Bangladesh is also under its threat. The lower snthern part of the country may go under water one day. So we should prevent the pollution of the environment to save our only planet.