Late Quaternary climates of East Asia deduced from the total organic carbon contents of cored sediments (MD179-3304, 3312) off Joetsu City,Japan Sea |
| |
| Institution: | 1. Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford OX1 3TG United Kingdom;2. Department of Geography, Tokyo Metropolitan University, Minamiosawa, Hachioji, Tokyo, Japan;3. Department of Geology, Trinity College Dublin, Dublin 2, Ireland;4. Research Centre for Palaeoclimatology, Ritsumeikan University, Kyoto 603-8577, Japan;5. Scottish Universities Environmental Research Centre, University of Glasgow, Scotland, United Kingdom;6. Centre for Ocean Science Drilling, Japan Agency for Marine-Earth Science Technology, Yokohama, Japan;7. Institute for Geothermal Science, Kyoto University, Kyoto 606-8502, Japan.;8. Faculty of symbiotic Systems Science, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan;9. Department of Solid Earth Geochemistry, Japan Agency for Marine-Earth Science and Technology, Yokosuka 237-0061, Japan;1. Department of Geography, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji City, Tokyo 192-0397, Japan;2. Department of Earth Sciences, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba City, Chiba 263-8522, Japan |
| |
| Abstract: | Total organic carbon (TOC) and total nitrogen (TN) concentrations are analyzed with high temporal resolution (ca. 100 years) for cores MD179-3304 and MD179-3312 taken from the Japan Sea off Joetsu City. The temporal changes in TOC and TN concentrations vary quasi-regularly in similar patterns. The age models are formed on the basis of the dates of 14C dating, marker tephra beds, TL layers, and marine isotope events with depth. TOC concentration is high in MIS 1 and 5, low in MIS 2 and 4, and slightly elevated in MIS 3 with frequent short fluctuations. This general trend is very similar to LR04 curve, except for the reduced dominance of TOC around the MIS 5.5 substage. As shown typically in MIS 3, there are many peaks of TOC in a short interval. The details of these TOC peaks can be correlated with the warm interstadials of the Greenland ice core. We can identify a sawtooth-like decreasing trend of TOC in MIS 3. In contrast, the decreasing trend of δ18O in the ice core corresponds to an increasing trend of TOC in MIS 5.The most plausible explanation for the correlation of climate changes between East Asia and the North Atlantic is oscillation of the Arctic polar front through time. The detailed correspondence of TOC concentrations of the Japan Sea sediments to other common paleoclimate proxies means that the TOC concentrations of these sediments is an excellent paleoclimate record in Far East Asia, although the genetic relationship between air temperature and biological productivity in the Japan Sea is as yet unknown. |
| |
| Keywords: | Total organic carbon High resolution Climate change Japan Sea sediment D–O cycle Biological productivity |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
