Geology tells us there were river beds in the Sahara, the Mediterranean Sea pretty much dried up, we had so much CO2 that ferns were as tall as trees, the Great Lakes were formed by glaciers, and Eur-Asia was connected to to North America. (i.e. the Native Americans didn’t swim here!)
A few years ago a pre-historic shark fossil was found in the Peruvian desert.
The earth’s climate has been all over the place even before man existed.
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