A study was performed in which each of the greenhouse gases was removed one by one and the greenhouse effect of the resultant gas-mix studied. The greenhouse effect dropped the most when water vapor was removed. This indicates that water vapor contributes the most to the greenhouse effect. In general, there seems to be an agreement that water vapor causes more greenhouse effect than carbon dioxide. There are a few positive feedback loops involved; analysis is at the point when equilibrium between all loops is attained.