News / Science & Technology

Climate Hastened Collapse of Angkor, Capital of Ancient Khmer Empire

Scientist uses tree rings to reconstruct 13th century climate

Climate Hastened Collapse of Angkor, Capital of Ancient Khmer Empire
Climate Hastened Collapse of Angkor, Capital of Ancient Khmer Empire

Multimedia

Audio
TEXT SIZE - +
Art Chimes

For hundreds of years the Khmer empire ruled in what is now Cambodia.

But in the 13th century, the capital city, Angkor, died off, and a new scientific study indicates that climate, specifically decades of drought interspersed with intense monsoons, helped bring down the Khmer capital.

In the ancient world, Angkor was known for its sophisticated water system.

"Angkor was really the dominant civilization in that part of the world without any question," said Brendan Buckley, the Columbia University scientist who led the study.

"It was the center of their universe. And it was called the 'hydraulic city' because it had really remarkably massive arrays of barays, which are these giant water tanks and a series of canals and interconnected waterways that was really unparalleled in the ancient world in that part of the world."

Buckley isn't an archaeologist. He studies tree rings, which record the growth history of trees that can be hundreds of years old, or even older. A new ring is added every year, and thicker rings represent a kind of savings account, when the tree collects more nutrients than it can use. Thin rings show the tree is barely getting along, like during a drought year.

Using samples from around Southeast Asia, Buckley and his colleagues saw this pattern in tree rings from recent years, when he could corroborate the rings with other historical climate information. His newest tree ring samples, from the rare Fokienia hodginsii cypress in southern Vietnam, enabled him to take the climate record back much further.

"We realized we have trees that are more than 1,000 years old. And we started seeing these big, giant periods of drought that took place around that time. And as I started to get more interested in the history of Southeast Asia, I realized that that was the time of the collapse of Angkor."

The research team used what are called core samples from hundreds of trees throughout Southeast Asia. Using a hollow tube, they drill into the tree and extract a 5-mm wide cylinder that shows each ring starting with the most recent, just under the bark.

By comparing rings from different trees and with other historical data, you can often identify particular rings with the exact calendar year that they grew.

"We were able to match up the narrow and wide rings exactly so that we can assign the exact calendar dates to the exact rings of every tree," Buckley explained. "In the tropics, a lot of tree species don't even form rings that we can see. So to be able to get a tree that, first of all, has very clear rings that we're able to visually match to each other and then go through and produce these long records was remarkable."

You May Like

Multimedia Parents of Disaster Ferry Passengers Lash Out at Authorities

Twenty-nine bodies recovered from water but some 270 remain trapped on board More

War Legacy Haunts Vietnam, US Relations

US congressional delegation initiates $84 million Agent Orange cleanup project More

Wikipedia Proves Useful for Tracking Flu

Technique gave better results than Center for Disease Control (CDC) and Google’s Flu Trends More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Ukraine, Russia, United in Faith, Divided in Politicsi
X
Michael Eckels
April 19, 2014
There is a strong historical religious connection between Russia and Ukraine. But what role is religion playing in the current conflict? In the run-up to Easter, Michael Eckels in Moscow reports for VOA.
Video

Video Ukraine, Russia, United in Faith, Divided in Politics

There is a strong historical religious connection between Russia and Ukraine. But what role is religion playing in the current conflict? In the run-up to Easter, Michael Eckels in Moscow reports for VOA.
Video

Video Face of American Farmer is Changing

The average American farmer is now 58 years old, and farmers 65 and older are the fastest growing segment of the population. It’s a troubling trend signaling big changes ahead for American agriculture as aging farmers retire. Reporter Mike Osborne says a new report from the U.S. Census Bureau is suggesting what some of those changes might look like... and why they might not be so troubling.
Video

Video Donetsk Governor: Ukraine Military Assault 'Delicate But Necessary'

Around a dozen state buildings in eastern Ukraine remain in the hands of pro-Russian protesters who are demanding a referendum on self-rule. The governor of the whole Donetsk region is among those forced out by the protesters. He spoke to VOA's Henry Ridgwell from his temporary new office in Donetsk city.
Video

Video Drones May Soon Send Data From High Seas

Drones are usually associated with unmanned flying vehicles, but autonomous watercraft are also becoming useful tools for jobs ranging from scientific exploration to law enforcement to searching for a missing airliner in the Indian Ocean. VOA’s George Putic reports on sea-faring drones.
Video

Video New Earth-Size Planet Found

Not too big, not too small. Not too hot, not too cold. A newly discovered planet looks just right for life as we know it, according to an international group of astronomers. VOA’s Steve Baragona has more.
Video

Video Copts in Diaspora Worry About Future in Egypt

Around 10 percent of Egypt’s population belong to the Coptic faith, making them the largest Christian minority in the Middle East. But they have become targets of violence since the revolution three years ago. With elections scheduled for May and the struggle between the Egyptian military and Islamists continuing, many Copts abroad are deeply worried about the future of their ancient church. VOA religion correspondent Jerome Socolovsky visited a Coptic church outside Washington DC.
Video

Video Critics Say Venezuelan Protests Test Limits of Military's Support

During the two months of deadly anti-government protests that have rocked the oil-rich nation of Venezuela, President Nicolas Maduro has accused the opposition of trying to initiate a coup. Though a small number of military officers have been arrested for allegedly plotting against the government, VOA’s Brian Padden reports the leadership of the armed forces continues to support the president, at least for now.
Video

Video More Millenials Unplug to Embrace Board Games

A big new trend in the U.S. toy industry has more consumers switching off their high-tech gadgets to play with classic toys, like board games. This is especially true among the so-called millenial generation - those born in the 1980's and 90's. Elizabeth Lee has more from an unusual café in Los Angeles, where the new trend is popular and business is booming.
Video

Video Google Buys Drone Company

In its latest purchase of high-tech companies, Google has acquired a manufacturer of solar-powered drones that can stay in the air almost indefinitely, relaying broadband Internet connection to remote areas. It is seen as yet another step in the U.S. based Web giant’s bid to bring Internet to the whole world. VOA’s George Putic reports.
AppleAndroid