Water vapor makes up roughly 75% of all greenhouse gas forcing. It makes up roughly 95% of all of the green house gases in our atmosphere. This is done through the evaporation of water and is a natural process.
The second largest force in terms of green houses gases is CO2. This makes up 9 to 26% of all green house heating. 94% of this gas is produced through the rotting of dead plants. Man is responsible for the remaining 6% of this gas. Man produces this gas by burning that material that would rot or by the burning of fossil fuels to mover cars, heat homes or fuel industry. The largest single portion of this is produced (over 50%) by heating and powering homes. Man also prevents a great deal of CO2 from being produced by using lumber that is cut from forests. This causes a artificial carbon sink. The wood inside a structure decays slower and thereby does not enter the atmosphere.
The remaining gases make up virtually no additional heating.
The largest source of removing CO2 from our atmosphere is our oceans. They remove 70% of the CO2.
Having said this we can determine how these gases are made. 80 to 90% of all greenhouse gases are made by water evaporating from the oceans. Another 10 to 20% are made from rotting vegetation or life forms that have died and are decaying.
The remaining 0.28% is man made. Over half of this is due to our homes. Heating, air conditioning and power for our homes make up OVER 50% of what we create. The remaining 0.13% (or other half from man) is due to our transportation needs. These includes bringing vegetables and fruit from other areas to our local tables.
Another example of man producing CO2 is to exhale. Another issue such as METHANE would be through farting. Man is not alone as the animals contribute to green house gases as well. As for the planets, they love us and take in the CO2 and release another greenhouse gas we all call OXYGEN.