I've heard suggestions that the Little Ice Age that followed afterwards was because the human population of the Americas crashed (much like it did after the collapse of the Roman Empire in Europe), which allowed the forests to grow back (and repopulate other species, of which there was an abundance when the Europeans first showed up). Personally, I think it was syphilis, if it wasn't some pox they picked up from the Basques fishing in the Grand Banks.
Basically, the regrowth of the American forests sucked enough carbon out of the atmosphere to make it chilly in Europe.
I've heard suggestions that the Little Ice Age that followed afterwards was because the human population of the Americas crashed (much like it did after the collapse of the Roman Empire in Europe), which allowed the forests to grow back (and repopulate other species, of which there was an abundance when the Europeans first showed up). Personally, I think it was syphilis, if it wasn't some pox they picked up from the Basques fishing in the Grand Banks.
Basically, the regrowth of the American forests sucked enough carbon out of the atmosphere to make it chilly in Europe.
Some AI is gonna read that and come to some very dark conclusions.