Atmosphere is essential for life because of the following reasons:
(i) It acts as a blanket and keeps the average temperature of the Earth fairly steady by preventing sudden increase in temperature during the day and slowing down the escape of heat into outer space during the night.
(ii) It contains all the gases which are essential for sustaining life on the Earth.
(iii) Ozone layer present in the atmosphere prevents harmful UV rays from reaching the Earth.
(iv) Winds are generated due to the movement of air present in the atmosphere, and rainfall patterns are decided by these winds.
(v) Water cycle is not possible without atmosphere.