Caltech Researchers Use Stalagmites to Study Past Climate Change

Many existing historical climate records are biased to the high latitudes— coming from polar ice cores and North Atlantic deep ocean sediments. Yet a main driver of climate variability today is El Niño, which is a completely tropical phenomenon. All of this begs the question: How do we study such tropical climate influences? The answer: stalagmites.

"Stalagmites are the ice cores of the tropics," says Jess Adkins, professor of geochemistry and global environmental science. He and geochemist Kim Cobb of the Georgia Institute of Technology led a team that collected samples from stalagmites in caves in northern Borneo and measured their levels of oxygen isotopes to reconstruct a history of the tropical West Pacific's climate over four glacial cycles during the late Pleistocene era (from 570,000 to 210,000 years ago).