Palm trees once thrived in the Antarctic 52 million years ago
(13 August 2012)
The study, published in the journal Nature, highlights the extreme contrast between modern and past climatic conditions on Antarctica and the extent of global warmth during periods of elevated atmospheric carbon dioxide (CO2) levels. Around 52 million years ago, the concentration of this greenhouse gas in the atmosphere was more than twice as high as today. The international team analysed fragments of plants and bacteria found in a 1km long drill core. This fossil data was compared against a new map of the ancient Antarctic landscape developed by Dr Jamieson and colleagues to reconstruct past temperatures and vegetation distributions.
Dr Stewart Jamieson said “The results are important because they provide a window into a world where atmospheric CO2 concentrations were high and show just how warm Antarctica has been in the past. The data help us understand how climate might respond in the future as greenhouse gas concentrations continue to rise as a result of human activity. This in turn aids efforts to predict the future stability of the Antarctic Ice Sheet and the knock-on implications for global sea level.”
52 million years ago, the Wilkes Land coast of Antarctica was covered by near-tropical forests as they today occur in NE Australia (see main image), whereas today this region is icebound (see image inset).
Pross, J., Contreras, L., Bijl, P.K., Greenwood, D.R., Bohaty, S.M., Schouten, S., Bendle, J.A., Röhl, U., Tauxe, L., Raine, J.I., Huck, C.E., van de Flierdt, T., Jamieson, S.S.R., Stickley, C.E., van de Schootbrugge, B., Escutia, C., Brinkhuis, H., IODP Expedition 318 Scientists (2012). Persistent near-tropical warmth on the Antarctic continent during the early Eocene epoch. Nature, DOI: 10.1038/nature11300.