Scientists drilling into the seabed off the coast of Antarctica have made a very interesting discovery that was announced this week. The sediment cores obtained during the drilling reveal that 52 million years ago a rainforest grew in Antarctica. 52 million years is most definitely a long time, but changing from a tropical rain forest to a constantly frozen land is a huge change in temperature.
The scientists are using the discovery as a warning of global warming saying that Antarctica could be ice-free again within decades. The sediment cores the team of researchers recovered revealed fossilized pollens. According to the scientists, those pollens came from a near-tropical forest that covered the entire continent of Antarctica during the Eocene period between 34 and 56 million years ago.
An Australian scientist named Kevin Welsh, who was part of the 2010 expedition, said that his team had discovered temperature-sensitive molecules in the cores showing that Antarctica was as warm at around 68°F 52 million years ago. Welsh and his team believe that higher levels of carbon dioxide in the atmosphere millions of years ago were the major reason that Antarctica was much warmer than it was today.
The scientist estimates that carbon dioxide during the time when Antarctica was warm reached between 992 to a couple thousand parts per million on the continent of Antarctica. CO2 levels today are estimated to be at about 395 ppm on the continent. Scientists believe that the ice that covers Antarctica today is between 1.9 and 25 miles thick with formation believed to have occurred about 34 million years ago.