Collaborative Research: CarboMODE: Carbon Dioxide Dynamics in Mode Water of the North Atlantic Ocean

合作研究：CarboMODE：北大西洋模式水中的二氧化碳动力学

• 批准号: 0623034
• 负责人: Scott Doney
• 金额: $ 18.69万
• 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: 2007-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0623034&HistoricalAwards=false
• 关键词: Collaborative; Research; CarboMODE; Carbon; Dioxide

The formation of mode waters, like Eighteen Degree Water (EDW) in the North Atlantic Ocean, is important for driving ocean circulation, ventilating and transferring biogeochemical properties to the ocean interior. Recent studies suggest that EDW plays an important role in setting the nutrient reservoir of the subtropical gyre [Jenkins and Doney, 2003; Doney and Jenkins, 2004; Palter et al., 2005], with significant implications for nutrient and carbon dynamics, and productivity in the subtropical gyre of the North Atlantic. In addition, EDW has a potentially important role in the ocean uptake and decadal variability of atmospheric CO2 [Bates et al., 2002]. In this study, researchers at the Bermuda Biological Station for Research (BBSR) and the Woods Hole Oceanographic Institution (WHOI) hope to achieve a better quantitative and mechanistic understanding of the CO2 dynamics in EDW. The work leverages the 2006-2007 field program and improved understanding about the physics of EDW that an NSF sponsored field project, CLImate MOde water Dynamics Experiment (CLIMODE) will gain. The main question posed in CarboMODE is "What is the oceanic uptake and fate of CO2 in EDW in the North Atlantic Ocean?" From this general question, more specific questions are raised, including: (1) What is the air-sea CO2 flux during wintertime EDW formation? (2) What are the relative contributions from vertical/lateral mixing, advection/stirring, air-sea CO2 gas exchange and biological depletion of CO2 due to net community production during EDW formation that influence the DIC properties of EDW? (3) What is the dissolved inorganic carbon (DIC) content of EDW upon subduction (injection) into the subtropical gyre and what is the overall flux? (4) How does the formation of EDW impact the subsurface inorganic carbon reservoir and air-sea CO2 fluxes in the subtropical gyre of the North Atlantic Ocean? (5) What is the fate of inorganic carbon in EDW as it advects away from the region of formation and how does subsurface remineralization contribute to the DIC content of EDW? In addressing these questions, the investigators propose will collect inorganic carbon data in 2007 as part of the CLIMODE project. Their contribution to the CLIMODE (and CarboMODE) project will be measurements of DIC, Total Alkalinity (TA) and underway pCO2 (i.e., seawater and air pCO2). Although focused on physics, the observational and modeling program framed by CLIMODE's questions and hypotheses fortuitously provide a timely and unique opportunity to address questions raised about CO2 dynamics (and related issues concerning nutrient and dissolved oxygen dynamics). Synthesis and modeling of several different datasets, including the 2007 CLIMODE field surveys of EDW, CO2 data collected from a 2006 CLIMODE cruise, a 4 day northward extension of the BATS Bermuda-Puerto Rico annual transect, and surface seawater pCO2 (and DIC and alkalinity) data collected twice a week in the region of EDW formation from the Volunteer Observing Ship (VOS) MV Oleander (funded by NOAA COSP), form the nucleus for addressing relevant CarboMODE questions. In terms of broader impacts, this study will provide fundamental data on the oceanic sink of CO2 into North Atlantic EDW layer and will contribute to carbon cycle studies coordinated under a variety of science programs and implementation structures (e.g., NACP, CCSP, OCCC, SOLAR-IMBER) that aim to establish accurate estimates of oceanic CO2 sources and sinks, and the underlying mechanisms that regulate it. The project will support one full time post-doctoral fellow at BBSR. Scientific understanding and research products from the research will be used in undergraduate and graduate educational activities at BBSR, and contribute to the research and technical skills of two research technicians, and one undergraduate student from WHOI.

模式沃茨的形成，如北大西洋的18度水（EDW），对于驱动海洋环流、通风和向海洋内部转移生物地球化学性质是重要的。最近的研究表明，EDW在设置亚热带环流的营养库方面起着重要作用[Jenkins和Doney，2003; Doney和Jenkins，2004; Palter等人，2005年]，与营养和碳动力学的重大影响，在北大西洋亚热带环流的生产力。此外，EDW在海洋吸收和大气CO2的十年变化中具有潜在的重要作用[Bates等人，2002年]。在这项研究中，百慕大生物研究站（BBSR）和伍兹霍尔海洋学研究所（WHOI）的研究人员希望对EDW中的CO2动态进行更好的定量和机械理解。这项工作利用了2006-2007年的实地项目，并提高了对美国国家科学基金会赞助的实地项目CLImate MOde水动力学实验（CLIMODE）将获得的EDW物理学的理解。CarboMODE提出的主要问题是“北大西洋EDW中CO2的海洋吸收和命运是什么？“从这个一般性的问题，提出了更具体的问题，包括：（1）什么是冬季EDW形成期间的海气CO2通量？(2)垂直/横向混合、平流/搅拌、海-气CO2气体交换和生物消耗对EDW形成过程中影响EDW DIC性质的净群落产生的CO2的相对贡献是什么？(3)EDW俯冲（注入）到亚热带环流后的溶解无机碳（DIC）含量是多少？总通量是多少？(4)EDW的形成如何影响北大西洋副热带环流的地下无机碳库和海气CO2通量？(5)EDW中无机碳的命运是什么，因为它从形成区域平流离开，地下矿化作用如何影响EDW的DIC含量？为了解决这些问题，研究人员建议在2007年收集无机碳数据，作为CLIMODE项目的一部分。他们对CLIMODE（和CarboMODE）项目的贡献将是DIC、总碱度（TA）和正在进行的pCO 2（即，海水和空气pCO 2）。虽然侧重于物理学，但CLIMODE的问题和假设框架的观测和建模程序偶然提供了一个及时和独特的机会来解决有关CO2动态（以及有关营养和溶解氧动态的相关问题）的问题。几个不同数据集的合成和建模，包括2007年CLIMODE EDW实地调查，2006年CLIMODE巡航收集的CO2数据，BATS波多黎各-波多黎各年度样带向北延伸4天，表层海水pCO 2每周两次从志愿观测船（VOS）MV Oleander收集EDW形成区域的DIC和碱度数据（由NOAA COSP资助），形成解决相关CarboMODE问题的核心。就更广泛的影响而言，这项研究将提供关于CO2进入北大西洋EDW层的海洋汇的基本数据，并将有助于在各种科学计划和实施结构（例如，NACP，CCSP，OCCC，SOLAR-IMBER），旨在建立海洋CO2源和汇的准确估计，以及调节它的基本机制。该项目将支持BBSR的一名全职博士后研究员。从研究的科学认识和研究产品将用于本科生和研究生教育活动在BBSR，并有助于两个研究技术人员的研究和技术技能，从WHOI的一个本科生。