A research group consisting of 19 members from 11 institutes in Japan and overseas including Associate Professor Ryu Uemura, from the Faculty of Science at the University of the Ryukyus, and Professor Keisuke Suzuki, from the Faculty of Science at Shinshu University, uncovered variations of temperatures in the Antarctic, and the water temperatures of the surrounding waters, over the past 720,000 years, through analysis of the Antarctic Dome Fuji ice core*1 drilled by the Japanese Antarctic Research Expedition. The research, which compiled data recovered from ice cores including that of seawater temperatures, broke the former record of 420,000 years by 300,000 years. Accurately predicting climate changes such as global warming has been a major social issue. This research reveals the relationship between variations in CO2 concentrations, the amount of solar radiation, and temperature variations in the past when the environment was substantially different, and is expected to help understand the mechanism of climate change on Earth. The results of this research were posted online on Nature Communications on March 6, 2018.

*1 ice core: Cylindrical ice samples obtained by drilling into the Antarctic and Arctic ice sheets. Dome Fuji ice core, which was used in this research, was drilled during the period from 2003 to 2007 in the Japanese Antarctic Research Expedition “The Second Dome Fuji Ice Core Project.”