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).
Excerpt from the document:
Over the past several decades a great deal of international effort has been undertaken to show that anthropogenic CO2 is causing climate change on the planet by raising the planets temperature. The increased temperatures will then change climate patterns which will result in the melting of the worlds glaciers increased storms and probably loss of valuable crop lands.
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