晚第四纪热带西太平洋海气CO_(2)交换影响因素

Influencing factors of air-sea CO_(2) exchange in the Western Tropical Pacific during the late Quaternary

探究海气CO_(2)交换有助于解析全球碳循环和全球气候变化。由于海水和大气的直接接触,研究表层海水碳酸盐系统变化成为探究海气碳交换的关键。基于已有热带西太平洋表层海水碳酸盐系统研究成果,本文总结了有孔虫壳体B/Ca和δ11B指标重建碳酸盐系统参数的原理、方法及优缺点。然后,从厄尔尼诺-南方涛动(El Ni?o-Southern Oscillation, ENSO)、东亚季风以及大气桥梁和海洋隧道三方面综述了晚第四纪热带西太平洋海气CO_(2)交换影响因素的研究现状。结果显示,类ENSO通过横向平流和垂向变化分别影响热带西太平洋东端和西端的海气碳交换。东亚夏季风对热带西太平洋海气碳交换具有较强的调控作用,而东亚冬季风的调控作用较弱或不明显。冰消期南大洋深部流通状况增强,可通过大气桥梁(大气CO_(2))和海洋隧道(南极中层水)影响热带西太平洋海气碳交换。然而,为了更准确清晰地了解全球碳循环变化,还需针对指标记录的可靠性、覆盖范围以及海气碳交换在更长时间尺度的变化机理等方面开展更多研究。

Exploring air-sea CO_(2) exchange helps to analyze the global carbon cycle and global climate change.Due to the direct contact between seawater and atmosphere,characterizing the changes in the carbonate system of surface water is the key to explore the air-sea CO_(2) exchange.Available studies of the sea surface carbonate system in the Western Tropical Pacific(WTP)was reappraised,the principles,methods,advantages and disadvantages of reconstructing carbonate system parameters with foraminiferal B/Ca andδ11B were summarized.Secondly,the research status of influencing factors of air-sea CO_(2) exchange in the WTP during the late Quaternary was reviewed from three aspects:El Niño-Southern Oscillation(ENSO),East Asian monsoons,and atmospheric bridge and ocean tunnel.Results show that the ENSO-like processes can affect the air-sea CO_(2) exchange in the eastern and western parts of the WTP via lateral advection and vertical change,respectively.The East Asian summer monsoon regulates the air-sea CO_(2) exchange in WTP strongly and effectively,while the East Asian winter monsoon,weakly and insignificantly.During the deglaciation period,the increased ventilation of deep water in the Southern Ocean affects the air-sea CO_(2) exchange in the WTP through the atmospheric bridge(atmospheric CO_(2))and ocean tunnel(Antarctic Intermediate Water).In the future,more researches are required into the reliability and coverage of proxy records,and the mechanisms of air-sea CO_(2) exchange over longer time scales,to understand changes in the global carbon cycle more accurately and clearly.