Mayan Civilization’s Demise Might Have Been Man-Made, Due to Deforestation and Drought

The demise of the Mayan civilization might have been discovered after its extinction in 900 AD.

Scientists have concluded that the civilization collapsed from deforestation and drought, and place those causes on the Mayans themselves.

"We're not saying deforestation explains the entire drought, but it does explain a substantial portion of the overall drying that is thought to have occurred," said lead author of the study Benjamin Cook, a climate modeler at Columbia University's Lamont-Doherty Earth Observatory and the NASA Goddard Institute for Space Studies.

The scientists noted the Mayans tore down trees to assist in their cities and crops, but in doing so and ultimately relying on corn reduced the amount of water transferred from the soil to the atmosphere, which reduces rainfall.

The experiment to calculate such theories included a climate-model simulation where it can determine how much the switch from the reliance of crops over forest use would affect climate.

Results in the experiment suggest that when deforestation reached its peak, it could make up to 60 percent of the dry spell.

The conclusion further supports another study by researcher Martin Medina-Elizalde of the Yucatan Center for Scientific Research in Mexico and Eelco Rohling, a paleoclimatologist at the University of Southampton in England regarding the Mayan drought.

"Our results show rather modest rainfall reductions between times when the Classic Maya civilization flourished and its collapse between 800 to 950," said Rohling to Live Science. "These reductions amount to only 25 to 40 percent in annual rainfall, but they were large enough for evaporation to become dominant over rainfall, and open water availability was rapidly reduced. The data suggest that the main cause was a decrease in summer storm activity."

The study is published in the online journal Geographical Research Letters.