*Without the [[greenhouse effect]] life on this planet would probably not exist as the average temperature of the Earth would be a chilly -18° Celsius, rather than the present 15° Celsius.<ref>[http://www.physicalgeography.net/fundamentals/7h.html Introduction to the Atmosphere]</ref> | *Without the [[greenhouse effect]] life on this planet would probably not exist as the average temperature of the Earth would be a chilly -18° Celsius, rather than the present 15° Celsius.<ref>[http://www.physicalgeography.net/fundamentals/7h.html Introduction to the Atmosphere]</ref> |