How do greenhouse gases make life on Earth possible.

Green house gases make life on earth possible by producing green house effect that keeps the Earth warm.

Explanation:

Earth recieves heat energy in the form of incoming solar radiation. Some part of the incoming solar radiation is absorbed in the atmosphere but maximum of it reaches the Earth's surface. Earth in turn re-radiates this long wave thermal radiation. Maximum amount of this re-radiated heat Is absorbed by some gases in the atmosphere. These radiatively active gases that absorbs this radiating heat are called Greenhouse gases. These greenhouse gases act as a thermal blanket around the Earth, raising the temperature of the Earth. This effect is called Green house Gases.