摘要
频繁的千年尺度气候波动是冰期气候的典型特征。末次冰期时,南极和格陵兰在千年尺度呈现出反相位的温度变化:当格陵兰气候处于暖期时南极缓慢降温,当格陵兰处于冷期时南极缓慢升温。这种南北极遥相关现象被称为Bipolar Seesaw。Bipolar Seesaw对气候的影响是全球性的,并且Bipolar Seesaw背后的物理过程与冰期大气CO;浓度变化密切相关。因此,研究Bipolar Seesaw对于理解冰期气候的运行机制,探究大气CO;变化的控制因素,具有重要意义。目前学界对末次冰期Bipolar Seesaw现象的观测研究已较为全面,但Bipolar Seesaw的具体机制仍有众多问题未得到解决。本文综述了近年来国际上关于Bipolar Seesaw的研究进展,并归纳了Bipolar Seesaw未来的几个研究方向。
Background,aim,and scope During the last glacial period,Greenland ice cores recorded 25 millennial-scale climate fluctuations called Dansgaarde-Oeschger events characterized by abrupt transitions (about decades) between relatively warm and cold climate states.During the cold and warm phase of the Dansgaarde-Oeschger events,the Antarctic gradually warms and cools respectively,leaving the “Antarctic isotope maximums” in isotope temperature archives.This anti-phase interhemispheric teleconnection is called the “Bipolar Seesaw” and is accompanied by the large-scale reorganization of global oceanic and atmospheric circulation and the variations in atmospheric carbon dioxide concentration.Currently,many problems of the Bipolar Seesaw are still unsolved.Thus,we here reviewed the researches of the Bipolar Seesaw to constrain the progress,problems,and future research directions.Materials and methods We focused on the researches of the recent two decades and reviewed the observational characteristics of the Bipolar Seesaw,the mechanism of Dansgaarde-Oeschger events and the Antarctic isotope maximums,and the connections between Bipolar Seesaw and millennial-scale atmospheric carbon dioxide concentrations.Results Even though the observational characteristics (e.g.the timing of each event,the lag of bipolar signal transfer) of the Bipolar Seesaw of the last glacial period is already well studied.We outlined the following issues:the mechanism of the Dansgaarde-Oeschger events,the dynamical processes that link the Dansgaarde-Oeschger events and the Antarctic isotope maximums,and the cause for the connections between millennial-scale atmospheric carbon dioxide changes and the Bipolar Seesaw.Discussion We discussed the following issues:the challenges for the current hypotheses of the Dansgaarde-Oeschger events.The contribution of deep-ocean heat release for the Antarctic isotope maximums.And the inconsistency between millennial-scale atmospheric CO;and the Antarctic temperature behavior.Conclusions Thus,despite the progre
作者
郑培松
赖忠平
ZHENG Peisong;LAI Zhongping(School of Earth Sciences,China University of Geosciences,Wuhan 430074,China;Institute of Marine Sciences,Guangdong Provincial Key Laboratory of Marine Biotechnology,Shantou University,Shantou 515063,China)
出处
《地球环境学报》
CSCD
2021年第5期455-470,共16页
Journal of Earth Environment
基金
汕头大学科研基金(NTF19003)。
