Collecting Deep-sea Corals from off of Tasmania to Measure the History of Southern Ocean Radiocarbon Concentrations

从塔斯马尼亚附近收集深海珊瑚来测量南大洋放射性碳浓度的历史

• 批准号: 0648618
• 负责人: Jess Adkins
• 金额: --
• 依托单位: California Institute of Technology
• 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: 2007-04-01 至 2009-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0648618&HistoricalAwards=false
• 关键词: Collecting; Deep; sea; Corals; off

In the Southern Ocean, Antarctic Intermediate Water (AAIW) and sub-Antarctic Mode Water (SAMW) set the properties of the base of the tropical thermocline, and therefore play an important role in the tropics' ability to alter global climate. Antarctic Bottom Water (AABW) fills much of the global abyssal depths, and is therefore the most important reservoir in measuring the ocean's ability to store and release CO2. For these reasons, the rate at which these water masses ventilate the intermediate and deep ocean is a key parameter in many theories of glacial-interglacial climate change, and rapid climate shifts. This proposal will constrain the Southern Ocean's history by collecting fossil deep-sea corals from south of Tasmania to then measure the past profiles of Delta14C, at ice core resolution. Radiocarbon is the crucial tracer because its inherent time information lets us constrain deep circulation rates. The waters south of Tasmania are known to contain abundant modern and fossil corals and the bathymetry of the region is well suited to find samples between 500 and 3,000 meters deep. In this project, I plan to conduct a a two-cruise sampling program; cruise 1 will map and survey the area with the CSIRO vessel Southern Surveyor and the Autonomous Benthic Explorer (ABE) from WHOI, cruise 2 will collect and characterize corals from the key locations identified in cruise 1 with a UNOLS vessel and the ROV Jason. The PI will archive all samples and make them available to all researchers who wish to work on them. A web-basedprogram of daily updates and background information geared towards middle school science students is planned for the cruises.

在南大洋，南极中层水（AAIW）和亚南极模态水（SAMW）决定了热带温跃层的基底性质，因此在热带改变全球气候的能力中发挥着重要作用。南极底层水（AABW）填充了全球大部分深海深度，因此是衡量海洋储存和释放CO2能力的最重要水库。由于这些原因，这些水团覆盖中层和深海的速度是许多冰川-间冰期气候变化和快速气候变化理论的关键参数。这项提案将通过收集塔斯马尼亚南部的深海珊瑚化石来限制南大洋的历史，然后以冰芯分辨率测量Delta 14 C的过去剖面。放射性碳是关键的示踪剂，因为它固有的时间信息可以让我们限制深层循环速率。塔斯马尼亚岛南部的沃茨已知含有丰富的现代和化石珊瑚，该地区的水深测量非常适合在500米至3,000米深的地方找到样本。在这个项目中，我计划进行两次巡航取样方案;第一次巡航将与澳大利亚科学与工业研究组织的南方测量船和世界卫生组织的自主海底探测器一起对该地区进行测绘和调查，第二次巡航将与联合国海洋法办事处的一艘船只和Jason号海洋探测器一起从第一次巡航中确定的关键地点收集珊瑚并确定其特征。PI将存档所有样本，并将其提供给所有希望对其进行研究的研究人员。 一个基于网络的每日更新和背景信息的方案，面向中学生科学的学生计划巡航。