Japan Geoscience Union Meeting 2016

Presentation information


Symbol M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS17] Paleoclimatology and paleoceanography

Tue. May 24, 2016 10:45 AM - 12:15 PM A04 (APA HOTEL&RESORT TOKYO BAY MAKUHARI)

Convener:*Tomohisa Irino(Faculty of Environmental Earth Science, Hokkaido University), Minoru Ikehara(Center for Advanced Marine Core Research, Kochi University), Akira Oka(Atmosphere and Ocean Research Institute, The University of Tokyo), Yusuke Okazaki(Department of Earth and Planetary Sciences, Graduate School of Science, Kyushu University), Ikuko Kitaba(Research Centre for Palaleoclimatology, Ritsumeikan University), Akihisa Kitamura(Institute of Geosciences, Faculty of Science, Shizuoka University), Masaki Sano(Research Institute for Humanity and Nature), Ryuji Tada(Department of Earth and Planetary Science, Graduate School of Science, The Univeristy of Tokyo), Takeshi Nakagawa(Ritsumeikan University), Akira Hayashida(Department of Environmental Systems Science, Doshisha University), Chair:Akira Oka(Atmosphere and Ocean Research Institute, The University of Tokyo)

10:45 AM - 11:00 AM

[MIS17-19] Decadal to centennial-scale Asian dust transport changes during the last thousand years recorded in Lake Suigetsu sediment

★Invited papers

*Kana Nagashima1, Yoshiaki Suzuki2, Takeshi Nakagawa3, Ryuji Tada2, Tsuyoshi Haraguchi4, Katsuya Gotanda5 (1.Japan Agency for Marine-Earth Science and Technology, Research and Development Center for Global Change, 2.Department of Earth and Planetary Science, The University of Tokyo, 3.Ritsumeikan University, 4.Department of Geoscience, Osaka City University, 5.Faculty of Policy Informatics, Chiba University of Commerce)

Keywords:Asian dust, last 1000 years, Lake Suigetsu, decadal-vriation, centennial-variation

Knowledge of decadal to centennial-scale variations in Asian dust transport is critical to understand the interactions between Asian dust and natural environment, and is also important to estimate past atmospheric circulation changes. Here we estimated temporal changes in the content and depositional flux of aeolian dust in sediment core SG12 from Lake Suigetsu, central Japan, during the last thousand years based on the depositional flux (please see Suzuki et al., presented in this session) and grain size of detrital materials.
First we focused on the last century and compared the estimated dust flux changes to the meteorological records. The estimated dust flux shows decadal-scale change with the decrease during 1952–1974, which could be explained by weaker westerlies in lower latitudes including central Japan, reflecting weaker Aleutian Low during the corresponding period.
Similar decadal-scale changes are observed throughout last thousand years, suggesting dominance of similar decadal-scale climate systems in the East Asia and the north Pacific. In addition, the dust record exhibits centennial-scale changes with the decreases during 11–12th, 15th and 18–19th centuries. We will further compare our result with pollen record from Lake Suigetsu and tree-ring records in Asian region, and discuss nature and mechanisms of decadal and centennial-scale climate changes in East Asia.