But the evidence for the Medieval Warm Period is persistent, global, and growing.
This current study about population levels in Cahokia is another datum confirming the existence of the Medieval Warm Period. It also shows warmer was more productive, and better for human populations.
the same medieval warming period stopped the rains over central america starting about 800 AD. The Mayans sacrificed themselves to bring back the rains. They were so weak after so much self sacrifice that the Toltecs moved in and started raiding other city states. They took nobles priests and warriors captive for their human sacrifices. By 1000AD they mayan cities were emptied.
I too was thinking about the Medieval warm period coinciding with the time of ‘climate change’ mentioned in the article. A connection the author did not mention. I wonder if the archaeologists are taking that in account or just looking at Cahokia in isolation from the rest of global weather patterns and climatology?