[RayChuang88]

As soon as early man figured out how to tame the use of fire, any continent with large numbers of the predecessors to homo sapiens sapiens (modern Man) was going to change the climate of the land anyway. Going from essentially zero to many thousands of small fires (and the occasional large fire to clear land) was going to change the climate anyway.

[JimRed]

Going from essentially zero to many thousands of small fires (and the occasional large fire to clear land) was going to change the climate anyway.

Local conditions? Maybe, but even that's a stretch. But climate? Not a snowball's chance.