Sediment Cores From Antarctic Seabed Reveal Ancient Rain Forest
Drilling of the seabed off Antarctica has revealed that rainforest grew on the frozen continent 52 million years ago, scientists said, warning it could be ice-free again within decades. The study of sediment cores drilled from the ocean floor off Antarctica’s east coast revealed fossil pollens that had come from a “near-tropical” forest covering the continent in the Eocene period, 34-56 million years ago.
Kevin Welsh, an Australian scientist who travelled on the 2010 expedition, said analysis of temperature-sensitive molecules in the cores had showed it was “very warm” 52 million years ago, measuring about 68 F. “There were forests existing on the land, there wouldn’t have been any ice, it would have been very warm,” Welsh told AFP of the study, published in the journal Nature. Welsh said higher levels of carbon dioxide in the atmosphere were thought to be the major driver of the heat and ice-free conditions on Antarctica, with CO2 estimates of anywhere between 990 to “a couple of thousand” parts per million. CO2 is presently estimated at about 395ppm.