The main reason for the existence of climatic regions on our planet is the tilting of the Earths vertical axes and the elliptic rotation of the Earth around the sun. This causes the amount of incoming solar radiation to vary throughout a year. As a result we have four seasons each lasting around 90 days.
There has been much ado about CO2 levels, the amount of it, who's responsible and its influence on our climate (if any). But it seems that 0,04% CO2 has not the effect on temperature some might think.
Excerpt from the document:
A recent study has revealed that the Earth’s natural atmospheric greenhouse effect is around 90 K or about 2.7 times stronger than assumed for the past 40 years. A thermal enhancement of such a magnitude cannot be explained with the observed amount of outgoing infrared long-wave radiation absorbed by the atmosphere (i.e. ≈ 158 W m-2), thus requiring a re-examination of the underlying Greenhouse theory.
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