Washington, April 29 : Newly discovered ancient Antarctic sediment cores will give international scientists a close-up look at fluctuations that occurred in Antarctica's ice sheet and marine and terrestrial life as the climate cooled considerably between 20 and 14 million years ago.
Collected by Florida State University's (FSU) Antarctic Marine Geology Research Facility, the sediment cores were extracted from deep beneath the sea floor of Antarctica's western Ross Sea, the Earth's largest floating ice body.
The new samples - segments of a drill core that measures more than 1,100 meters in length - offer an extraordinary stratigraphic record of sedimentary rock from the Antarctic continental margin that documents key developments in the area's Cenozoic climatic and glacial history.
By correlating that stratigraphic record with existing data and climate and ice sheet models, scientists from FSU and around the world expect to learn how local changes in the Southern Ocean region relate to regional and global climate events.
According to Sherwood W. Wise, Jr., an FSU geological science professor, "Such knowledge will significantly increase our understanding of Antarctica's potential responses to future global-scale climate changes."
"This is critical for low-lying regions such as Florida that could be directly affected by the future behavior of the Antarctic Ice Sheets and any resulting sea-level changes. By studying these glacial records of the past, geologists and climatologists seek to better predict the future," he added.
The research team will re-examine the latest core acquisitions to refine their descriptions of the material and take additional samples for tests to extract even more information about their history and the conditions under which the sediments were deposited.
"The sediment cores recovered during this year's successful ANDRILL (ANtarctic geological DRILLing) expedition have filled in a major gap in the most direct record of the ice activity yet recovered from the period of about 20 to 14 million years ago," said Wise.
"The 1,139 meters of core retrieved, 98 percent intact, records the critical transition from times warmer than today to the onset of major cooling between about 14 to 13 million years ago when a semi-permanent ice sheet formed across most of Antarctica," he added.