CARDIFF, Wales, Sept. 15 (UPI) — U.K. and U.S. scientists have linked, for the first time, declining carbon dioxide levels and the formation of the Antarctic ice caps 34 million years ago.
The team of scientists from Cardiff, Bristol and Texas A&M universities extracted microfossils in samples of East African rocks that show the level of CO2 in the Earth’s atmosphere at the time of the formation of the ice-caps.
“About 34 million years ago the Earth experienced a mysterious cooling trend,” said Cardiff University Professor Paul Pearson, who led the study. “Glaciers and small ice sheets developed in Antarctica, sea levels fell and temperate forests began to displace tropical-type vegetation in many areas. The period, known to geologists as the Eocene-Oligocene transition, culminated in the rapid development of a continental-scale ice sheet on Antarctica, which has been there ever since.”
Assistant Professor Bridget Wade of Texas A&M University added, “Our study is the first to provide a direct link between the establishment of an ice sheet on Antarctica and atmospheric carbon dioxide levels and therefore confirms the relationship between carbon dioxide levels in the atmosphere and global climate.”
The research that included Gavin Foster from the University of Bristol is reported in the early online edition of the journal Nature.
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