Glacial Radiocarbon Constraints from Drake Passage Deep-Sea Corals

德雷克海峡深海珊瑚的冰川放射性碳限制

• 批准号: 0636787
• 负责人: Laura Robinson
• 金额: --
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2009-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0636787&HistoricalAwards=false
• 关键词: Glacial; Radiocarbon; Constraints; Drake; Passage

This project uses radiocarbon in deep-sea corals to understand the Southern Ocean's role in modulating global climate. A key site of deep-water formation, the Southern Ocean is critical to exchange of heat and carbon between the deep-ocean and atmosphere. Changes in it may be linked to low atmospheric CO2 during the last glacial maximum through increased biologic carbon draw down or decreased air-sea CO2 exchange. Testing these hypotheses is challenging because of the scarcity of suitable records of the Southern Ocean's biogeochemistry and circulation. The aragonitic skeletons of deep-sea corals may offer insight because they are well suited for radiocarbon analyses-reflective of the 14C content of the past water column--while also allowing for timing of events through U-series age measurements. Overall, these measurements will put new constraints on the extent of air-sea gas exchange, polar water-column stratification, and the flux of Southern-sourced deep water to the rest of the world's oceans. As a part of this work, new sections of the Drake Passage sea floor will be mapped and imaged, along with the present and past distributions of deep-sea corals and their habitats. A significant broader impact of this work is characterizing the functioning of what may be a key control of atmospheric CO2 content, which could prove important for fully understanding the impacts of continued CO2 emissions and developing mitigation strategies. As well, the work will characterize deep marine ecologies that are poorly understood, but increasingly exploited as fisheries resources.

该项目使用深海珊瑚中的放射性碳来了解南大洋在调节全球气候中的作用。南大洋是深水形成的关键地点，对于在深海洋和大气之间的热量和碳交换至关重要。在最后一次冰川最大的最大生物学碳通过增加或减少的空气海二氧化碳交换，它的变化可能与低大气中的二氧化碳有关。检验这些假设是具有挑战性的，因为缺少南大洋生物地球化学和循环的适当记录。深海珊瑚的后骨骨骼可能会提供洞察力，因为它们非常适合过去水柱的14C含量的放射性碳分析 - 反射 - 同时还允许通过U系列年龄的测量时间进行事件的时间。总体而言，这些测量结果将对空气天然气交换，极地水下分层以及南部采购的深水的通量构成新的限制。作为这项工作的一部分，将绘制和成像Drake Passage海底的新部分，以及深海珊瑚及其栖息地的当前和过去分布。 这项工作的一个重大广泛影响是表征可能是大气二氧化碳含量的关键控制的功能，这对于充分理解持续的二氧化碳排放和制定缓解策略的影响可能很重要。同样，这项工作将描述深海生态的特征，这些生态学知之甚少，但越来越多地被视为渔业资源。