Was reading ‘Megafloods’ Spurred Collapse of Ancient City of Cahokia, New Study Finds and it mentions a dramatic shift from “wet” to “dry” starting then and lasting until ca. 1200 ce when the Cahokia civ began to decline.
“Our study shows that Cahokia emerged during an unusually arid period in midcontinental North America, when large floods were suppressed,” said Sam Munoz, a geographer at the University of Wisconsin, who led the current research.
“But [it] began to decline after A.D. 1200, when large floods became more frequent.”
Did this climate shift have global impact? Does the timing have more than coincidental relation to events in Europe such as the Dark Ages and emergence from it?
I asked a more cause-oriented version (e.g. Howcum this climate shift happened?) on r/askscience. Link to that in a minute, on me mobile.
Thanks!
Within Mexico it certainly seems as though a long lasting drought took hold beginning in the late 6th century and early 7th century. This drought may have impacted Teotihuacan and led to its abandonment. Beekman and Christensen (2003, 2011 ) suggest that this drought triggered the Chichimec migrations which led to the formation of the Toltec state as well as the migrations in the Early and Late Pistclassic tied with the Aztec.