Exploring cyclic changes of the ocean carbon reservoir

Online Access: Get full text
doi: 10.1360/03wd0155
Author(s): Wang Pinxian; Tian Jun; Cheng Xinrong; Liu Quanlian; Xu Jian
Author Affiliation(s): Primary:
Tongji University, Shanghai, China
Volume Title: Chinese Science Bulletin
Source: Chinese Science Bulletin, 48(23), p.2536-2548. Publisher: Science Press, Beijing, China. ISSN: 1001-6538
Note: In English. 65 refs.; illus., incl. 2 tables
Summary: A 5-Ma record from ODP Site 1143 has revealed the long-term cycles of 400-500 ka in the carbon isotope variations. The periodicity is correlatable all over the global ocean and hence indicative of low-frequency changes in the ocean carbon reservoir. As the same periodicity is also found in carbonate and eolian dust records in the tropical ocean, it may have been caused by such low-latitude processes like monsoon. According to the Quaternary records from Site 1143 and elsewhere, major ice-sheet expansion and major transition in glacial cyclicity (such as the Mid-Brunhes Event and the Mid-Pleistocene Revolution) were all preceded by reorganization in the ocean carbon reservoir expressed as an episode of carbon isotope maximum (δ13Cmax), implying the role of carbon cycling in modulating the glacial periodicity. The Quaternary glacial cycles, therefore, should no more be ascribed to the physical response to insolation changes at the Northern Hemisphere high latitudes alone; rather, they have been driven by the "double forcing", a combination of processes at both high and low latitudes, and of processes in both physical (ice-sheet) and biogeochemical (carbon cycling) realms. As the Earth is now passing through a new carbon isotope maximum, it is of vital importance to understand the cyclic variations in the ocean carbon reservoir and its climate impact. The Pre-Quaternary variations in carbon and oxygen isotopes are characterized by their co-variations at the 400-ka eccentricity band, but the response of δ13C and δ18O to orbital forcing in the Quaternary became diverged with the growth of the Arctic ice-sheet. The present paper is the second summary report of ODP Leg 184 to the South China Sea.
Year of Publication: 2003
Research Program: ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 24 Surficial Geology, Quaternary Geology; C-13/C-12; Carbon; Carbon cycle; Carbonate sediments; Cenozoic; Geochemical cycle; Geochemical indicators; Geochemistry; Glacial environment; Isotope ratios; Isotopes; Leg 184; Marine environment; North Pacific; Northwest Pacific; ODP Site 1143; Ocean Drilling Program; Pacific Ocean; Paleo-oceanography; Paleoclimatology; Paleoenvironment; Quaternary; Sediments; South China Sea; Stable isotopes; West Pacific
Coordinates: N092143 N092143 E1131707 E1131707
Record ID: 2004046077
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.