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热带海区是全球水汽和热量传递的重要源区,其表层海水温度(SST)的变化必然会对高纬及全球气候变化产生重要影响,而热带与高纬气候变化的相位关系又是研究全球气候变化机制的关键.本研究展示了千年尺度上印度尼西亚穿越流(Indonesian Throughflow)出口处帝汶海区(Timor Sea)SO18459站位在倒数第2个冰消期(Termi-nationⅡ)的多种古海洋学记录,包括浮游和底栖有孔虫的δ18O,G.ruber Mg/Ca比值和表层海水δ18Ow等.G.ruber Mg/Ca比值显示,帝汶海区海水表层温度在TerminationⅡ的变化幅度约为4.1℃,且与浮游及底栖有孔虫的δ1?8O在TerminationⅡ时期几乎同相位变化.这一新的结果表明,千年尺度上热带海区的气候变化似乎与高纬的冰盖变化同步.此外,G.ruber Mg/Ca比值指示的SO18459站的SST记录表明,TerminationⅡ时帝汶海区的增温与南极增温几乎同时发生,这说明热带与南半球高纬之间存在着快速的热传输,而这种快速的热传输有可能通过大气的遥相关或者大洋上层水体来完成.SO18459站的G.ruberδ1?8O和SST在TerminationⅡ存在显著的回返事件,可能与澳大利亚季风降雨减少或西太平洋厄尔尼诺增强相关,但类似事件在东亚季风降雨记录中缺乏,说明热带地区不同气候系统对同一外部强迫如厄尔尼诺的响应并非完全一致,而是具有很强的地域性.全球底栖有孔虫δ1?8O的综合记录在TerminationⅡ也存在一类似的回返事件,说明了高纬和低纬气候在千年尺度上的遥相关.
The tropical sea area is an important source of global water vapor and heat transfer. The change of surface seawater temperature (SST) will inevitably have an important impact on high latitude and global climate change. The phase relationship between tropical and high latitude climatic changes is also a study of the global climate The Key to the Change Mechanism The present study presents a variety of paleoceanographic studies on the penultimate Termi-nation II site at the SO18459 site of the Timor Sea at the Indonesian Throughflow outlet on the millennium scale Records, including δ18O, G.ruber Mg / Ca ratios of planktonic and benthic foraminifera, δ18Ow of surface seawater, etc. The G.ruber Mg / Ca ratios show that the sea surface temperature in the Timor Sea has a variation of about 4.1 ° C , And is nearly in phase with that of the planktonic and benthic foraminifera during the TerminationⅡ period.The new results show that the climatic changes in the tropics at the millennial scale seem to be synchronized with the changes in the ice sheet at high latitudes.In addition, The SST record of SO18459 station indicated by the ratio of .ruber Mg / Ca shows that the warming of Timor Sea region occurred almost simultaneously with Antarctic temperature during Termination Ⅱ, which indicates that there is a rapid between tropical and high latitude in southern hemisphere Of the heat transfer, and this rapid heat transfer may be through the atmospheric teleconnection or ocean water body to complete.SO18459 station G.ruberδ1? 8O and SST in Termination Ⅱ significant return events, may be associated with the reduction of the Australian monsoon rainfall Or El Niño in the western Pacific, but similar events are absent in the record of monsoon rainfall in East Asia, indicating that the responses of different climate systems in the tropical region to the same external force such as El Niño are not exactly the same but have strong regional characteristics. The integrated records of insects δ1-δ8 also present a similar return event in TerminationⅡ, indicating the teleconnection of high-latitude and low-latitude climates at the millennium scale.