Minerals taken from lagoons reveal a century-long drought occurred between A.D. 800 and A.D. 900, right when the Mayan civilization disintegrated.
Minerals taken from Belize's famous underwater cave, known as the Blue Hole, as well as lagoons nearby, show that an extreme, century-long drought occurred between A.D. 800 and A.D. 900, right when the Mayan civilization disintegrated. After the rains returned, the Mayans moved north — but they disappeared again a few centuries later, and that disappearance occurred at the same time as another dry spell, the sediments reveal.
Rise and decline
From A.D. 300 to A.D. 700, the Mayan civilization flourished in the Yucatan peninsula. These ancient Mesoamericans built stunning pyramids, mastered astronomy, and developed both a hieroglyphic writing system and a calendar system, which is famous for allegedly predicting that the world would end in 2012.
But in the centuries after A.D. 700, the civilization's building activities slowed and the culture descended into warfare and anarchy. Historians have speculatively linked that decline with everything from the ancient society's fear of malevolent spirits to deforestation completed to make way for cropland to the loss of favored foods, such as the Tikal deer.
The evidence for a drought has been growing in recent years: Since at least 1995, scientists have been looking more closely at the effects of drought. A 2012 study in the journal Science analyzed a 2,000-year-old stalagmite from a cave in southern Belize and found that sharp decreases in rainfall coincided with periods of decline in the culture. But that data came from just one cave, which meant it was difficult to make predictions for the area as a whole, Droxler said.
The main driver of this drought is thought to have been a shift in the intertropical convergence zone (ITCZ), a weather system that generally dumps water on tropical regions of the world while drying out the subtropics. During summers, the ITCZ pelts the Yucatan peninsula with rain, but the system travels farther south in the winter. Many scientists have suggested that during the Mayan decline, this monsoon system may have missed the Yucatan peninsula altogether.
The team found that during the period between A.D. 800 and A.D. 1000, when the Mayan civilization collapsed, there were just one or two tropical cyclones every two decades, as opposed to the usual five or six. After that, the Maya moved north, building at sites such as Chichen Itza, in what is now Mexico.
But the new results also found that between A.D. 1000 and A.D. 1100, during the height of the Little Ice Age, another major drought struck. This period coincides with the fall of Chichen Itza.
The findings strengthen the case that drought helped usher in the long decline of the Mayan culture.