The freezing landmass of Antarctica wasn’t always the infertile scenery that we all know today. According to researchers, 90 million years ago, Antarctica may have been enclosed in a temperate rainforest.
The international team of scientists analysed sediment cores taken from the west Antarctic layer and discovered forest soils, roots, pollen and spores, representing the continent had an ‘exceptionally warm climate’ during the mid-Cretaceous period, the era when dinosaurs ruled the planet. The study was published in a journal named Nature.
Johann Klages, author and geologist at the Alfred Wegener Institute of Germany, said, “During the initial shipboard assessments, the unusual colouration of the sediment layer quickly caught our attention; it differed from the layers above it. We had found a layer originally formed on land, not in the ocean.”
Till date, nothing was known about the environment of the south of the Antarctic Polar Circle. Tina van de Flierdt, study co-author and professor in the Imperial College London’s Department of Earth Science and Engineering said, “The preservation of this 90-million-year-old forest is exceptional, but even more surprising is the world it reveals. “Even during months of darkness, swampy temperate rainforests were able to grow close to the South Pole, revealing an even warmer climate than we expected.”
“To get a better idea of what the climate was like in this warmest phase of the Cretaceous, we first assessed the climatic conditions under which the plants’ modern descendants live,” Klages said.
The conclusion draws a unique image of the South Pole, where West Antarctica’s coast was free of the ice sheets that cover it now, and wet rainforests covered the part instead.
But one question is still unanswered: ‘How did Antarctica withstand temperate rainforests without year-round sunlight?’ The scientists examined the stages of carbon dioxide that would have been in the climate at the time.
Researchers found carbon dioxide was greater than likely based on current climate modules. The carbon dioxide has a roasting consequence on the atmosphere and the planet, generating a greenhouse effect by deceiving heat from the Sun.
The larger amount of carbon dioxide, shared with an ice piece-less Antarctica covered in vegetation shaped the accurate situations for a rainforest environment.
Torsten Bickert, the co-author and geoscientist at the University of Bremen’s MARUM research centre in Germany, Torsten Bickert said, “We now know that there could easily be four straight months without sunlight in the Cretaceous. But because the carbon dioxide concentration was so high, the climate around the South Pole was nevertheless temperate, without ice masses.”
But the scientists still have not concluded that what caused Antarctica to cool off enough to form ice layers. The next challenge waits.