Global warming

http://magma.nationalgeographic.com/ngm/0409/feature1/

Do you feel hot? Do not ask why. Actually, you must ask yourself this question “am I the cause of this hot day?” Nowadays, global warming becomes the serious problem that the earth faces. A lot of people still do not care about this serious problem.
The earth has been turned so hot. In this hot situation, there is a strange thing that comes to my mind. That thing is that the earth used to be frozen around 400 hundred years ago, it was chilly and cold, and suddenly it becomes this hot.
A lot of people think that this is caused by the change of nature. They think that the sun has become closer to the earth, so it turns the earth hotter, but I do not thing this kind of thing can be happened. Some other people thing that a climate is just a passing through condition, it just lasts for a while, and the changed to the others.
Actually, the main cause of the global warming is the human itself. After those chilly years, people were starting to do the industrial revolution. The human were starting to clear the forest to become the land for their manufacture buildings. They did not think that the forest may slow the warming of the earth. Even in the industry, they are using a lot of coal, oil and gases. The industrial processes turn all of these materials into a carbon dioxide gas, the main cause of global warming. That gas’s concentration is now much higher than before.
This may affect to the other living being, not just human. The scientists have predicted that the polar bears will extinct in 30 years.
Although they have known all of these, some of the people are still unaware of this situation. Why? It is because, it happen so slowly; the process is very long. The people have never thought about how to prevent it, as they do not know that something serious shall be happened on those warm days.
Scientists are still looking for the way to slow the process of the global warming. They are trying to make the other source, such as hydrogen, as the main source of energy.
If the scientists are trying to do something, we must contribute to prevent the global warming too. So now, do you want to turn off your air-con to slow this warming process?