2013 Fiscal Year Final Research Report

Quantitative palaeotemperature reconstruction on MIS1, 5e, 11 interglacial episodes based on pollen assemblages from Lake Biwa sediments

Research Project

Project/Area Number	23540553
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Stratigraphy/Paleontology
Research Institution	Natural History Museum and Institute, Chiba
Principal Investigator	OKUDA Masaaki 千葉県立中央博物館, その他部局等, 研究員 (10311383)
Project Period (FY)	2011 – 2013
Keywords	古環境 / 古気候 / 琵琶湖 / 花粉分析 / モダンアナログ法 / 将来予測 / MIS11 / 温暖化
Research Abstract	Using pollen analysis and modern analogue techniques (MAT) for Lake Biwa sediment (Japan), I present palaeotemperature levels of MIS1, MIS5e, MIS11 interglacials by quantitative reconstruction from fossil pollen percentage datasets. The MIS5e and MIS11 are seen as "analogues for the warmer Earth climate" because of their resemblance to the present climate state. Here I reveal that Lake Biwa (37N; Shiga Pref) was as warm as the Shionomisaki Cape (33.5N; Wakayama Pref) at the MIS11 interglacials 430,000 years ago. This temperature anomaly is calculated as 1-1.5 degrees warmer than the Hypsithermal episode 7000 years ago, and 2-2.5 degrees warmer than the preindustrial period 300 years ago. This warmer climate was rather lower than the expected global warming, but is similar when our effort to reduce atmospheric CO2 is successful. As there are no catastrophic evident known at MIS11 in geological records, this is a result encouraging us to confront with the global warming problem.

(1 results)