Forests and fires in Antarctica – what happened 90 million years ago

Scientists have discovered traces of forest fires in a sediment core from the Amundsen Sea in West Antarctica, dating back about 90 million years: charcoal, amber, and spores of peat moss. During the Late Cretaceous period, dense forests grew on the continent, with a warm and humid climate and an average temperature of around 12°C.

Researchers from the Alfred Wegener Institute in Bremerhaven have found evidence of forest fires in a sediment core from the Amundsen Sea in West Antarctica, dating back about 90 million years. The sample contains charcoal, amber, and spores of peat moss. Analysis of the charcoal shows it formed from the burning of soft coniferous wood at relatively low temperatures. Amber—fossilized tree resin—may have been released after damage, including from fire. The large number of peat moss spores indicates the existence of raised bogs. Study co-author Johann Klages noted the exceptionally good preservation of the forest soil. During the Late Cretaceous, Antarctica's climate was warm and humid, with an average temperature of about 12°C, and the continent was connected to Australia. Natural sources of ignition could have been thunderstorms and lightning. The first evidence of an ancient forest in the region was obtained in 2020.