Collaborative Research: Expedition 323 Objective Research on the Paleoceanography of the Bering Sea

该研究首次提供了白令海的上新世古海洋学观测资料，支持了IODP第323次考察的目标，即了解上新世和更新世期间影响气候变化的相关因素，包括上新世早期的温暖期，当时的二氧化碳分压水平与今天的水平相似。白令海与北极和太平洋之间的水团流动，北极冰量的变化，以及在此期间太平洋是否形成了密集的中间水，将作为过去气候变化的一些可能触发因素进行研究。从这次巡航中获得的高分辨率沉积物记录，具有相对较大的振幅信号，提供了一个独特的机会，可以了解高层大气中的绝缘变化如何通过气候系统传播，并进一步测试气候变化的轨道周期是否主要在23ky和40ky时间尺度上运行。本研究利用了古地磁、沉积学(如：（如粒度分析）和古生物学(如：微化石组合分析；d18O和d13C的测量（底栖生物和浮游有孔虫）。从这项研究中获得的信息对于理解冰盖、海洋和大气环流以及全球碳循环之间的基本驱动因素和反馈至关重要。更广泛的影响：该项目大大推进了以前在IODP重要考察中进行的大量投资。该调查获得的数据可以为古气候/海洋模式提供重要信息，并与IPCC AR4情景下的未来气候预估相关。该项目包括一个由早期和中期职业科学家组成的团队，并包括与IODP社区其他科学家的国际合作。还为本科和研究生教育以及公共宣传和教育提供支持。

This research provides the first Pliocene paleo-oceanographic observations from the Bering Sea and supports the objectives of IODP expedition 323 for understanding the associated factors influencing climate change during the Pliocene and Pleistocene, including a warm period of the early Pliocene, when pCO2 levels were similar to today¡¦s levels. The flow of water masses between the Bering Sea and the Arctic and Pacific oceans, changes in Arctic ice volume, and whether dense intermediate waters formed in the Pacific during this time will be investigated as some of the possible triggers of past climate change. The high resolution sediment records obtained from this cruise, with relatively large-amplitude signals, provide a unique opportunity to understand how insulation changes in the upper atmosphere propagate through the climate system and to further test if the orbital cycles of climate change primarily operate on 23ky versus 40 ky timescales. This study utilizes K % logging data from the cruise with paleomagnetic, sedimentological (eg., grain size analysis) and paleontological (eg., analysis of microfossil assemblages; d18O and d13C measurements of benthic and planktonic forams) measurements from the drill cores. The information expected from this study is critical for understanding the fundamental drivers and feedbacks between ice sheets, oceanic and atmospheric circulation and the global carbon cycle. Broader Impacts: This project significantly advances large investments previously made in an important IODP expedition. The data derived from this investigation can provide important information for paleoclimate/ocean models, and is relevant towards projections of future climate under IPCC AR4 scenarios. The project includes a team of early and mid-career scientists, and includes international collaborations with other scientists of the IODP community. Support is also provided for undergraduate and graduate education, and for public outreach and education.