Cause of the 100-year Maya "dark age" has been a mystery — until now
A plume of dark smoke filled the sky over southern Mexico. Below, waves of hot gas and rock rushed down volcanic slopes, killing any living thing in their path. The gas and rock mixed with rivers to create a thick, heavy flow of water and mud.
For days afterward the air was filled with ash. It fell like snow, jamming rivers to create massive floods that destroyed the agriculture. The year was A.D. 540. El Chichón, a small and previously unremarkable volcano, had plunged the Maya civilization into darkness.
At least that is the story according to a new paper published in the February issue of the journal Geology. There is a long-running archaeological debate about what drove Maya civilization into a century-long “dark age.”
The Maya civilization was one of the most sophisticated of its time. The Maya thrived from 250 to 900 and are widely considered the most advanced in the Americas before the Europeans arrived. They developed a writing system, accurate calendars and new math. They built pyramids that still cast their shadows today.
No One Has Been Able To Explain What Happened
But, a major mystery remains. For more than 100 years, the Maya stopped construction projects, deserted some areas and engaged in war. This dark age was first discovered 75 years ago, and no one has been able to explain it now. Some have speculated an earthquake or hurricane struck the area. Others think trade routes might have collapsed.
But now, there is a hint that there may have been a volcanic eruption. A volcano can send a large amount of sulfur particles rocketing into the air. They can easily spread across the globe. Once they reach the area over the North and South poles, they become trapped in the ice sheets below. This means they become a clue for scientists centuries later.
That is how Michael Sigl, a chemist in Switzerland, figured out that a massive eruption must have happened somewhere in the world at the start of the mysterious Maya “dark age.” Tree ring records indicate that sunlight-reflecting sulfur particles high in the atmosphere caused the global temperature to drop by 34.7 to 35.6 degrees Fahrenheit at the same time. A volcanic eruption had clearly rocked the world. But could scientists pinpoint its location?
Scientists Piece Together Clues
The answer came at a chance meeting. Sigl happened to meet Kees Nooren, a scientist from the Netherlands, at a conference. Nooren had been studying particles in lake water near the Gulf of Mexico. There, he found layers of volcanic ash, which he traced back to El Chichón around 540 using a technique called carbon dating. He later found out that Sigl was researching the sulfur spike that happened in the same year. Nooren thought he might know what had caused it.
The resulting study suggests that El Chichón erupted around the same time that sulfur particles got into the ice sheets. It also shows that this is the same year the Maya “dark age” began. Still, experts disagree on what the eruption’s exact effect on the Maya might have been. If the eruption could send particles halfway across the world, it would have caused harsher winters and also regional droughts.
This is what Payson Sheets, a U.S. archaeologist who was not involved in the study, thinks interrupted Maya civilization. When the powerful Maya city Tikal was devastated by drought, it was attacked by other Maya cities. Sheets thinks this caused the "dark age."
Questions About El Chichón's Effect On The Maya
But it is also possible that El Chichón did not cause these global changes. "There could be a different eruption there that we just don’t have any records of at the moment,” says Matthew Toohey, a climate scientist in Germany, who was not involved in the latest study. A number of studies have tried to link other tropical volcanoes to the sulfur spike, but the dates are less certain.
Researchers also are not sure if El Chichón’s eruption in 540 was massive enough for its effects to span the entire globe. Nooren’s team assumes it was as large as the eruption in 1982, which buried nine villages and killed 2,000 people.
However, even if the eruption was too small to have global effects, it could have helped it play a role in the Maya “dark age.” Nooren and other scientists think that the ash and flows of hot gas and rock from El Chichón could have easily thrown nearby cities into chaos.
Other archaeologists who were not part of this research agree the Maya civilization's "dark age" was likely caused by the volcano. But, this was a good thing, says Robin Torrence, an archaeologist from Australia. “People can often pick themselves up, dust themselves off and in many cases take advantage of new opportunities.” Those opportunities could have included the volcanic ash itself, which in small amounts can be a great fertilizer.
Large or small, an eruption of El Chichón likely played a role in the Maya’s mysterious "dark age."