A Beautiful Place for Research

January 22, 2015

The Maya were good at many things. They built incredible cities and temples, developed a written language to record their accomplishments, created a calendar, and in general mastered their environment enough to thrive for about 3,000 years. But despite their endurance, the culture suffered significant loss around 900 CE. Why?


By Dennis Jarvis from Halifax, Canada via Wikimedia Commons

For many decades, archeologists have wondered what brought this civilization down. One working theory was drought. Just as California has struggled with drought for the past three years, the region that is now Mexico, Belize, Guatemala, El Salvador, and Honduras may have experienced such severe lack of precipitation that most of the Maya people were extinguished.

But how do we find evidence of a drought that happened more than 1,000 years ago? Can we really tell which ancient years were dry and which were wet? Scientists believe we can, and they recently discovered another clue that points toward drought as the answer to the mystery of the Maya downfall. They found it in what’s called the Great Blue Hole, a 1,000-foot ocean crater about 40 miles off the coast of Belize.

That might sound like a strange place to learn about drought. Formed as a limestone cave system during the last ice age, the caves filled with water as sea levels rose, creating a circular basin about 400 feet deep. This huge bucket of ocean acts as a trap for sediment, where it forms layers of geological history for researchers to take core samples from and determine what the weather was doing, say, back in the year 900.

It turns out that between 800 and 1000, there were only one or two tropical storms every two decades in this region, where usually there were five or six. And while today we think of tropical storms as destructive forces of nature, they were what ancient cultures relied on to irrigate their farmlands before the invention of electric pumps. If the Maya found themselves with only one-fifth of their usual rainfall, they might not have been able to grow enough food for the civilization to survive. As advanced as they were, they were still bound by the whims of the natural world.

While most of us won’t be able to skip off to Belize for a diving expedition into the Great Blue Hole, we can see what it looks like through the powers of video – one thing the Maya didn’t manage to develop.