Climate researchers are able to gain insights into how our climate will develop in future by analyzing other interglacial periods that have occurred through the ages. Recently, a scientific team discovered some surprising new evidence in core samples taken in the Antarctic. These samples are the first witnesses to be obtained of the climate during an interglacial period that occurred some 52 million years ago. In their findings the team, whose members include Dr. Ursula Röhl from the University of Bremen‘s MARUM Institute, reveal the surprising fact that palm trees were indigenous to the Antarctic coastline during this period. The study will be published this month in the prominent journal Nature.
Some 52 million years ago the atmosphere of the Earth contained concentrations of the greenhouse gas that were more than twice that found today. “If current levels of CO2 emissions from the burning of fossil fuels continue unhindered, in a few hundred years the Earth will probably once again witness comparable concentrations of CO2”, explains Prof. Jörg Pross, paleoclimatologist at the Goethe-Universität Frankfurt and member of the Biodiversity and Climate Research Center (BiK-F). Dr. Ursula Röhl, marine geologist at MARUM, adds: “Research into earlier climate warming caused by natural phenomena makes a significant contribution to our knowledge of the mechanisms and processes at play in the climate system. This is an immense help in understanding the climate warming caused by mankind today.” Recent climate modeling indicates that future climate warming in the higher latitudes, i.e. in the polar regions, will reach particularly acute levels.
The samples of sediment obtained from drilling in the ocean bed off the coast of Wilkes Land in the Antarctic as part of the Integrated Ocean Drilling Program (IODP) are between 53 and 46 million years old. The pollen and spores they contain reveal that 52 million years ago the coastal regions of the Antarctic were covered by tropical to subtropical rain forests.
Where today the Antarctic ice cap demarcates the Southern Ocean, in years gone by it was possible for extremely frost-susceptible plants like palm trees and the precursors of today’s baobab trees to flourish. Scientific analysis shows that in the past the average temperature along the Antarctic coastline was a mild 10°C – even in winter and despite the three-month polar night. Towards the heart of the continent, though, it became appreciably cooler and home to a more temperate rain forest of southern beech and araucaria of the type found in New Zealand today. Additional evidence of extremely mild temperatures is supplied by analysis of the organic compounds produced by soil bacteria. Millions of years ago these micro-organisms could also be found in the soil of the coastal regions of Wilkes Land.
Further information / requests for interviews / graphics and photos:
Albert Gerdes
MARUM Public Relations
Phone: 0421 218 65540
e-mail: agerdesprotect me ?!marumprotect me ?!.de
Sabine Wendler
LOEWE Biodiversität und Klima Forschungszentrum (BiK-F),
Press Officer
Phone: 069 7542 1838
e-mail: sabine.wendlerprotect me ?!senckenbergprotect me ?!.de
