*Shuji Fujita^1,2, Frédéric Parrenin Parrenin^3,4, Ayako Abe-Ouchi^5,6, Kenji Kawamura^1,2, V. MASSON-DELMOTTE⁷, Hideaki Motoyama^1,2, Fuyuki Saito SAITO⁶, M. Fujita SEVERI⁸, B. STENNI⁹, Ryu Uemura¹⁰, E. W. Wolff¹¹ (1.National Institute of Polar Research, Research Organization of Information and Systems(ROIS), 2.Department of Polar Science, The Graduate University for Advanced Studies (SOKENDAI), 3.CNRS, LGGE, F-38041 Grenoble, France, 4.University Grenoble Alpes, LGGE, F-38041 Grenoble, France, 5.Atmosphere and Ocean Research Institute (AORI), University of Tokyo, Chiba, Japan, 6.Japan Agency for Marine–Earth Science and Technology, Yokohama, Japan, 7.Laboratoire des Sciences du Climat et de l’Environnement, Institut Pierre Simon Laplace, UMR CEA-CNRS-UVSQ-UPS 8212, Gif-sur-Yvette, France, 8.Department of Chemistry, University of Florence, Florence, Italy, 9.Department of Environmental Sciences, Informatics and Statistics, Ca’ Foscari University Venice, 30123 Venice, Italy, 10.Department Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Okinawa, Japan, 11.Department of Earth Sciences, University of Cambridge, UK)