VPW: Millenial Scale Variations in Thermohaline Circulation: A Pilo-Pleistocene Record from the ODP Leg162 North Atlantic Drift Sites

VPW：温盐环流的千年尺度变化：来自 ODP Leg162 北大西洋漂移点的 Pilo-更新世记录

• 批准号: 9627010
• 负责人: Suzanne O'Connell
• 金额: --
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-01 至 1998-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9627010&HistoricalAwards=false
• 关键词: VPW; Millenial; Scale; Variations; Thermohaline

Reconstructing and understanding past ocean circulation and heat transport are central to establishing the causes and mechanisms of long-term climate change. Ocean circulation directly influences the global environment through the formation of ice, by influencing oceanic and atmospheric CO2, and by heat transfer. Ice and marine records show millennial-scale changes in temperature and circulation during the last glacial interval, suggesting climate instability on very short time scales. The high-sedimentation-rate cores recovered during ODP Leg 162 provide a unique opportunity to investigate the millennial-scale stability of climate and thermohaline circulation over the last three million years. This will be accomplished by examining sedimentological parameters which are influenced by climate and current strength and comparing them to independently generated isotopic and faunal records. Four different climatic regimes will be investigated; the 100 kyr dominated late Pleistocene world with large marine based ice-sheets, the 41 kyr dominated world during the early Pleistocene and late Pliocene, and the mid-Pliocene warm interval before initiation of the Northern Hemisphere ice ages. Interactive activities focus on teaching a graduate course entitled "Drift Sedimentation in Modern and Ancient Oceans," collaborating with scientists at Cambridge University, and giving a lecture tour to college students in the U.S. as a U.S. Science Advisory Committee Distinguish Lecturer.

重建和了解过去的海洋环流和热量输送对于确定长期气候变化的原因和机制至关重要。海洋环流通过冰的形成、通过影响海洋和大气中的二氧化碳以及通过热传递直接影响全球环境。冰川和海洋记录显示，在最后一次冰川期间，温度和环流发生了千年尺度的变化，这表明气候在很短的时间尺度上不稳定。在ODP162航次期间发现的高沉积速率岩心为研究过去三百万年来气候和温盐环流的千年尺度稳定性提供了一个独特的机会。这将通过检查受气候和海流强度影响的沉积学参数，并将它们与独立产生的同位素和动物群记录进行比较来实现。将研究四种不同的气候模式：100KYR主导的晚更新世世界和大片海洋冰盖，41KYR主导的早更新世和晚上新世世界，以及北半球冰期开始之前的中上新世暖期。互动活动的重点是教授一门名为“现代和古代海洋的漂流沉积”的研究生课程，与剑桥大学的科学家合作，并作为美国科学咨询委员会杰出讲师对美国大学生进行巡回演讲。