POWRE: An Arctic Ocean Time-Series of Dissolved Inorganic Carbon

POWRE：北冰洋溶解无机碳时间序列

• 批准号: 9753170
• 负责人: Patricia Yager
• 金额: $ 7.5万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-10-01 至 1998-09-01
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9753170&HistoricalAwards=false
• 关键词: POWRE; Arctic; Ocean; Time; Series

POWRE: An Arctic Ocean time-series of dissolved inorganic carbon The goal of this research project is to evaluate seasonal patterns of biological production and respiration in the central Arctic Ocean with an emphasis on predicting the direction and extent of air-sea carbon exchange. This research would complement funded research at a year-long field-station (SHEBA) established in the perennial ice pack along the eastern edge of the Beaufort Sea. For the first time ever with modern methods, oceanographers will observe nearly all major components of the central Arctic marine carbon cycle with at least weekly resolution over an entire year. Funded Principle Investigators, Wheeler et al. and Welch et al., will measure dissolved oxygen and nutrients, particulate and dissolved organic carbon, autotrophic and heterotrophic biomass (ranging from picoplankton to polar bears), and primary and secondary production and respiration rates. These measurements will be made in the context of a larger surface heat budget experiment (NSF-SHEBA, DOE-ARM, NASA-FIRE, ONR-HLP) where many biogeochemically-relevant physical parameters will be monitored throughout the year. Two key parameters, total dissolved inorganic carbon (CT) and alkalinity (AT), needed to complete the carbon budget and link the Arctic Ocean ecosystem to the global carbon cycle, are as yet missing from the funded plan. This proposal is designed to provide these missing links. I propose to use weekly depth profiles of CT and AT in Arctic surface waters to detect the biological transformations of carbon between the dissolved inorganic (DIC) and organic carbon (OC) pools, specifically the extent of net primary production during the photic period, respiration rates during the dark wintertime, and the effect of springtime ice algae on near-surface DIC concentration. By measuring both CT and AT, we can calculate pCO2, needed to estimate gas exchange, and also use alkalinity as a tracer for contributions from rivers, sea-ice, and other water masses. While perennially ice-covered seas have been historically considered `net heterotrophic` ecosystems, these estimates have typically relied on summertime measurements. With a data set covering an entire annual cycle, we (myself and my collaborators) propose to test the following hypotheses: that 1) autotrophy exceeds heterotrophy during parts of the year, 2) a seasonal offset exists between autotrophic and heterotrophic production, 3) wintertime heterotrophy is supported by DOC produced locally during the spring and early summer, and 4) local production and respiration balance on an annual basis. By providing the link between biological processes and pCO2, my data would allow us to test additionally whether this region of perennially-ice covered Arctic seas (net heterotrophic, net autotrophic, or balanced) is, on an annual basis, a source or sink for atmospheric CO2. The POWRE award would have a significant impact on the career of Dr. Yager. As a new investigator, this award will provide an opportunity to enhance her research activities through access to state-of-the-art oceanographic field equipment and the opportunity to collaborate with an internationally known team of oceanographers.

power：北冰洋溶解无机碳的时间序列本研究项目的目标是评估北冰洋中部生物生产和呼吸的季节性模式，重点是预测海气碳交换的方向和程度。这项研究将补充在波弗特海东部边缘的常年浮冰上建立的为期一年的实地研究站（SHEBA）的资助研究。有史以来第一次，海洋学家将用现代方法观察北极中部海洋碳循环的几乎所有主要组成部分，在一年中至少每周进行一次分辨率。受资助的主要研究者Wheeler等人和Welch等人将测量溶解氧和营养物、颗粒和溶解有机碳、自养和异养生物量（从浮游生物到北极熊），以及初级和次级生产和呼吸速率。这些测量将在一个更大的表面热预算实验（NSF-SHEBA, DOE-ARM, NASA-FIRE, ONR-HLP）的背景下进行，该实验将全年监测许多生物地球化学相关的物理参数。完成碳预算和将北冰洋生态系统与全球碳循环联系起来所需的两个关键参数，总溶解无机碳（CT）和碱度（AT），目前还没有出现在资助计划中。本提案旨在提供这些缺失的环节。我建议使用北极地表水CT和AT的每周深度剖面来检测溶解的无机碳（DIC）和有机碳（OC）池之间的碳生物转化，特别是光期净初级生产的程度，黑暗冬季的呼吸速率，以及春季冰藻对近地表DIC浓度的影响。通过测量CT和AT，我们可以计算二氧化碳分压，用来估计气体交换，还可以使用碱度作为河流、海冰和其他水团贡献的示踪剂。虽然长期被冰覆盖的海洋在历史上被认为是“净异养”生态系统，但这些估计通常依赖于夏季的测量。利用覆盖整个年周期的数据集，我们（我和我的合作者）提出验证以下假设：1)自养在一年中的部分时间超过异养，2)自养和异养生产之间存在季节性抵消，3)冬季异养是由春季和初夏当地生产的DOC支持的，4)每年当地生产和呼吸平衡。通过提供生物过程和二氧化碳分压之间的联系，我的数据将使我们能够进一步测试这片常年被冰覆盖的北极海域（净异养、净自养或平衡）是每年大气二氧化碳的源还是汇。POWRE奖将对Yager博士的职业生涯产生重大影响。作为一名新的研究人员，该奖项将为她提供一个机会，通过使用最先进的海洋现场设备来加强她的研究活动，并有机会与国际知名的海洋学家团队合作。