During the Cretaceous Period, which started around 145 million years ago and ended around 66 million years ago, Antarctica was much warmer than it is today – and partly covered by rainforest. This is the result of a study published on Wednesday in the journal Nature.
In February and March 2017, researchers from the Universities of Gothenburg, Leicester and Dublin took drill samples from the shelf of the western part of Antarctica for their study. Her conclusion: The plant material contained in the samples indicates that the temperatures during the Cretaceous period could have been higher than previously thought.
Researchers are surprised by this thesis
CT scans of the approximately 90 million year old sediment core showed untouched samples of forest soil, pollen, spores and even root systems that were so well preserved that the researchers were able to identify cell structures. Overall, the team found evidence of more than 65 different types of plants.
Even the researchers themselves were surprised by their new thesis. “We didn’t know that the climate was so extreme during the chalk,” said Dr. Johann Klages from the Alfred Wegener Institute in Germany and co-author of the study with the Guardian. “It shows us what carbon dioxide can do.”
Investigations important for future climate change
If the researchers’ thesis is correct, then the average temperature in the chalk was around 12 to 13 degrees Celsius. Even the water had a comfortable temperature of around 20 degrees. A researcher says that such an area should have existed in the immediate vicinity of the South Pole only under certain circumstances. “The greenhouse gas concentration should have been higher than previously thought, and the land surface should have been covered with vegetation.”
Dr. James Bendle, an organic geochemistry expert at the University of Birmingham, told the Guardian that studying the Antarctic ecosystem is vital to understanding past and future climate change. “The undiminished use of fossil fuels could bring the carbon dioxide concentration to a level similar to that of 90 million years ago at the beginning of the next century.”