A multiple component subject though the underlying principle is very simple. Whenever an energy carrying gas arrives on the surface of planet earth that does not radiate all it’s energy to outer space tat is a greenhouse gas.
Greenhouse gasses have many sources though the one often talked about is the result of man made combustion of fossil fuels & thus avoidable by man.
In this subject I will attempt to highlight what humans have learned though I restate that I am but a layman.
An ever changing picture of the climate in Canada plus conjecture of the near future & since Canada is an integral part of planet earth to understand Canada means also understanding planet earth climate.
Scientists tell us that the outer layer of planet earth consists of generally solid land masses & oceans with a liquid core. This liquid core is molten rock &, for reasons & effects that will be described has an influence on the orientation of earth.
In general & either naturally or artificially earth provides a habitat for humans & other life forms.
Here is a link Planet Earth Physical (press)