Georgia Institute of Technology Assistant Professor of paleoclimatology Kim Cobb and graduate student Jud Partin studied stalagmites from two caves on the tropical Pacific island to determine how the Earth's climate suddenly changed several times during the past 25,000 years.
By analyzing the stalagmites, the researchers produced a high-resolution and continuous record of the climate affecting the equatorial rain forest.
"These stalagmites are, in essence, tropical ice cores forming over thousands of years," said Partin. "Each layer of the rock contains important chemical traces that help us determine what was going on in the climate thousands of years ago, much like the ice cores drilled from Greenland or Antarctica."
Partin and Cobb's research suggests the tropical Pacific played a much more active role in some of the abrupt climate change events of Earth's past than was once thought and might even have caused some of the changes.
Their findings are reported in the current issue of the journal Nature.