July 30, 2008

Study: Antarctica Had No Ice 40M Years Ago

Welsh scientists studying marine fossils say they've determined Antarctica 40 million years ago had warmer seas and little or no ice.

Catherine Burgess from Cardiff University's School of Earth and Ocean Sciences and colleagues studied the chemical analysis of exceptionally well preserved fossils of marine micro-organisms found in 40 million-year-old sediments on a cliff face in New Zealand.

Because the fossils are so well preserved, they provide more accurate temperature records, said Burgess. "Our findings demonstrate that the water temperature these creatures lived in was much warmer than previous records have shown. Although we did not measure carbon dioxide, several studies suggest that greenhouse gases 40 million years ago were similar to those levels that are forecast for the end of this century and beyond.

Our work provides another piece of evidence that, in a time period with relatively high carbon dioxide levels, temperatures were higher and ice sheets were much smaller and likely to have been completely absent, she added.

The research that included scientists from New Zealand's Institute of Geological and Nuclear Sciences, the University of Bristol and the Royal Netherlands Institute for Sea Research is reported in the August issue of the journal Geology.