Exploring cyclic changes of the ocean carbon reservoir

作     者：WANG Pinxian, TIAN Jun, CHENG Xinrong, LIU Quanlian & XU Jian Key Laboratory of Marine Geology, Ministry of Education, Tongji Uni-versity, Shanghai 200092, China 

作者机构：Key Laboratory of Marine Geology Ministry of Education Tongji University 

出 版 物：《Chinese Science Bulletin》 (CHINESE SCIENCE BULLETIN)

年 卷 期：2003年第48卷第23期

页      面：2536-2548页

核心收录：

学科分类：070702[理学-海洋化学] 07[理学] 0707[理学-海洋科学] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.49999560) the National Key Basic Research Special Fund(Grant No.G2000078500) 

主　　题：海洋 ODP 海洋钻探工程 碳循环 南中国海 地层学 

摘      要：A 5-Ma record from ODP Site 1143 has re-vealed 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 proc-esses 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 pre-ceded by reorganization in the ocean carbon reservoir ex-pressed as an episode of carbon isotope maximum (d 13Cmax), 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 揹ouble 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 impor-tance to understand the cyclic variations in the ocean carbon reservoir and its climate impact. The Pre-Quaternary varia-tions in carbon and oxygen isotopes are characterized by their co-variations at the 400-ka eccentricity band, but the response of d 13C and d 18O to orbital forcing in the Quater-nary 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.