Japan Geoscience Union Meeting 2016

Presentation information

Oral

Symbol H (Human Geosciences) » H-QR Quaternary research

[H-QR15] Diachronic dynamics of human-environment interactions

Thu. May 26, 2016 10:45 AM - 12:15 PM 101A (1F)

Convener:*Toshihiko Sugai(Department of Natural Environmental Studies, Institute of Environmental Studies, Graduate School of Frontier Science, The University of Tokyo), Kiyohide Mizuno(Institute of Geology and Geoinformation, National Institute of Advanced Industrial Science and Technology), Minoru YONEDA(The University Museum, The University of Tokyo), Chair:Minoru YONEDA(The University Museum, The University of Tokyo), Mamoru Koarai(Earth Science course, College of Science, Ibaraki University)

11:00 AM - 11:15 AM

[HQR15-08] Abrupt cooling event during the middle Holocene from pollen data of marine costal sediments in Uchiura bay, northern Japan

*Akihiro Yoshida1, Hodaka Kawahata2, Junko Habu3 (1.Kagoshima University, 2.Tokyo University, 3.Research Institute for Humanity and Nature)

Keywords:pollen data, palaeoclimatic reconstruction , modern analogue technique , Uchiura bay, northern Japan

Holocene climate records provide valuable information for inferring past interaction between humans and environment. We present well dated pollen data covering the last 7,000 years from Uchiura bay in southern Hokkaido, norther Japan, in order to better understand the change of human population for the Jomon sites around northern Japan. In addition, we show the palaeoclimatic reconstructions since the middle Holocene from the pollen data, using the best modern analogue technique (MAT). The pollen-based quantitative palaeoclimatic data in Uchiura bay indicate that small-scale cooling events took place at ca. 4.2-4.5 ka cal BP, 2.3-2.4 ka cal BP, and ca. 1.0-1.2 ka cal BP. From the data, the temperature at ca. 4.2-4.5 ka cal BP drastically decreased about 1.5 °C. The cooling at the period corresponds to the decrease of alkenone-SST in Uchiura bay and other palaeoclimatic records throughout East Asia. We can suggest that the abrupt cooling event at ca. 4.2-4.5 ka cal BP influenced human activities and population during the Jomon period in northern Japan.