Q. Consider the following statements:

1. Carbon dioxide released in the atmosphere creates a green house effect.
2. Without Carbon dioxide the earth would have been too hot to live in.
3. The increased level of Carbon dioxide is causing global warming.

Which of the above is / are correct?
Answer: Only 1 and 3
Notes: Carbon dioxide released in the atmosphere creates a green house effect by trapping the heat radiated from the earth. It is therefore called a greenhouse gas and without it the earth would have been too cold to live in. However, when its level in the atmosphere increases due to factory smoke or car fumes, the heat retained increases the temperature of the earth. This is called global warming. This rise in temperature causes the snow in coldest parts of the world to melt. As a result the sea level rises, causing floods in the coastal areas.