BOB HIRSHON (host):
Aging Antarctic Ice. I’m Bob Hirshon and this is Science Update.
When you think of krypton, Superman’s home planet probably springs to mind. But on our world, krypton is a gas that came here from outer space. Scientists are using it to age Antarctic ice and reconstruct the ancient climate. Oregon State University paleoclimatologist Christo Buizert says frozen ice stores a record of past carbon dioxide levels.
CHRISTO BUIZERT (Oregon State University):
Through studying ice cores, we’ve really learned a lot about our past climate and how it has evolved.
He says some krypton is radioactive, and decays at a predictable rate. To age an ice sample, he and his colleagues measure how much radioactive krypton still remains. Using the method, they found that ice on the edge of one Antarctic glacier is 120,000 years old. Back then, carbon dioxide levels were much lower than they are today. I’m Bob Hirshon, for AAAS, the science society.