Paleoceanography Research Team

Introduction

Understanding propagation mechanisms of global climate changes and the response of biogeochemical cycles to climate changes through the regional study of the Pacific and its adjacent seas.

Reconstruction of the past climate changes

Extending observational data toward the past by reconstructing climate variations with millennial, centennial, decadal time scale, using the paleo proxies recorded in marine and lake sediments and sediment trap samples.

Fig. 1. Map showing sediment traps and sediment cores which we are currently working on.

Collaboration between paleo-proxy and climate model

Understanding climate propagation processes by comparing results between proxies and paleo climate model simulations.
Collaboration with Axel Timmermann and Laurie Menviel at IPRC, University of Hawaii and Ayako Abe-Ouchi and Megumi Chikamoto at RIGC, JAMSTEC.

Fig. 2. An example for collaboration work between proxy and model: Deepwater formation in the North Pacific during the last deglaciation. Left: Ventilation changes in the western North Pacific during the last deglaciation based on sedimentary radiocarbon records. Right: Simulated radiocarbon age anomalies in the North Pacific between H1 and LGM. Both Both sedimentary radiocarbon record and modeling simulation strongly suggest that the deepwater in the North Pacific was sinking extending to a depth of ~2500 m.

More information: Press release

Proxy developments

Developing new paleo proxy and cultivation of zoo- and phyto-plankton.

Fig. 3-1: A detection of provenance of eolian dust based on cathodoluminescence using a single quartz particle (Cooperative work with Prof. H. Nishido and M. Kayama of Okayama University of Science).

Fig. 3-2: A simple method for measurements on oxygen isotope of biogenic silica based on carbon reduction using an induction heating (Cooperative work with Akira Ijiri of University of Tokyo).

Fig. 4. Upper panel: Chamber formation in planktonic foraminifer.
Lower panels: Living planktonic foraminifer species, Globigerinoides sacculifer (left), and Neogloboquadrina dutertrei (right).