Collaborative Research: Physical and biological controls on ocean carbon and oxygen uptake in the western North Pacific

合作研究：北太平洋西部海洋碳和氧吸收的物理和生物控制

• 批准号: 2049294
• 负责人: Manfredi Manizza
• 金额: $ 49.42万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2049294&HistoricalAwards=false
• 关键词: Collaborative; Research; Physical; biological; controls

Understanding the mechanisms that determine when and how the ocean takes up carbon from the atmosphere is important to our fundamental knowledge of ocean biogeochemistry and to our ability to model future climate. Air-sea fluxes of oxygen are also relevant to climatic variability, and surface oxygen can act as a tracer of biological carbon production and export as well as of important physical processes. The Kuroshio Extension region of the northwest Pacific Ocean is an area of strong carbon dioxide uptake and a site of wintertime watermass formation, with Subtropical Mode Water formed to the south of the Kuroshio Extension and lighter and denser Central Mode Water formed to the north. These mode waters then sink below the surface, moving carbon dioxide to the ocean interior. There are very few wintertime vertical profiles of any carbon system parameter in these mode water formation regions and no fully resolved winter or annual cycles of measurements. In this project, the investigators will deploy robotic profiling floats to make these needed measurements. They will combine the float data with numerical modeling to advance understanding of mode water formation and air-sea fluxes of carbon dioxide and oxygen in this important region. This proposal will fund an early career scientist and expand expertise in and capability for biogeochemical profiling float operations at the University of Hawai’i, providing a foundation for future work in autonomous biogeochemical platforms. This proposal will fund a graduate student in their Ph.D. work and multiple summer undergraduate researchers. Students will gain exposure to the complementary fields of marine chemistry, ocean physics, and climate models. The team will investigate carbon and oxygen budgets in the northwest Pacific from the following: new float observations of oxygen, nitrate, and estimated dissolved inorganic carbon; longer-term float temperature and salinity observations for water mass analysis; and model output. They will deploy biogeochemical Argo floats capable of measuring pH in the heart of the Subtropical and Central Mode Water formation regions in the Kuroshio Extension to provide vertical profiles of oxygen, nitrate, and, especially, estimates of dissolved inorganic carbon. They will use these observations to both calculate the drivers of air-sea carbon dioxide and oxygen fluxes and to validate model output for further analysis. Western boundary currents, such as the Kuroshio Extension, are areas of significant carbon dioxide uptake, but the relative importance of biology and physics to that uptake and its variability on large temporal and spatial scales is not well understood. The project has three main goals: (1) to determine what fraction of the CO2 and O2 uptake in the North Pacific is the result of mode water formation and subduction, (2) to determine how the physical and biological processes that drive air-sea fluxes vary spatially in the Kuroshio Extension region, and (3) to analyze the drivers of interannual and decadal variability of mode water formation and related gas fluxes in the Kuroshio Extension region and determine how that variability is linked to the larger climate system. The new observations will be evaluated in the larger context of multiple decades of observations from ships and almost two decades of physical observations from profiling floats. The team will use model output to diagnose physical drivers of air-sea fluxes and to link the observed mechanisms to longer-term variability and climate processes. The data collected will represent the first seasonally resolved profiles of oxygen, nitrate, and derived DIC in a western boundary current and will be of use to a broad community of researchers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

了解确定海洋何时以及如何从大气中占据碳的机制对于我们对海洋生物地球化学的基本知识以及我们对未来气候建模的能力很重要。氧气的空气通量也与杂交变异性有关，表面氧可以充当生物碳产生和出口以及重要物理过程的示踪剂。西北太平洋的黑鲁道延伸区是一个强大的二氧化碳吸收量和冬季水泥形成的地点，在黑鲁希岛延伸的南部形成了亚热带模式水，北部形成了较轻，更密集的中央模式水。然后，这些模式水沉入地面下方，将二氧化碳移至海洋内部。在这些模式的水形成区域中，任何碳系统参数的冬季垂直轮廓很少，没有完全解决的冬季或年度测量周期。在这个项目中，调查人员将部署机器人分析浮子以进行这些所需的测量。他们将将浮点数据与数值建模相结合，以提高对这一重要区域中二氧化碳和氧气的模式形成和空气通量的了解。该提案将为早期的职业科学家提供资金，并扩大夏威夷大学生物地球化学浮点运营能力的专业知识和能力，为未来在自动生物地球化学平台上工作的工作提供了基础。该建议将为博士学位的研究生提供资金。工作和多个夏季的本科研究人员。学生将获得海洋化学，海洋物理和气候模型的完整领域。该小组将从以下内容中调查西北太平洋地区的碳和氧气预算：氧气，硝酸盐和估计溶解的无机碳的新浮子观察；长期的浮点温度和盐度观察，用于水质量分析；和模型输出。他们将部署能够在黑素延伸的亚热带和中央模式水形成区域中测量pH值的生物地球化学Argo浮子，以提供氧气，硝酸盐，尤其是溶解的无机碳的估计值。他们将使用这些观察结果来计算空气二氧化碳和氧气的驱动因素，并验证模型输出以进行进一步分析。西部边界电流（例如黑鲁西奥延伸）是二氧化碳吸收量明显的区域，但是生物学和物理学对这种摄取及其对大型临时和空间尺度的可变性的相对重要性尚不清楚。该项目具有三个主要目标：（1）确定北太平洋中二氧化碳和O2的摄取的哪一部分是模式水的形成和俯冲的结果，（2）确定驱动空气通量的物理和生物学过程如何变化，在黑素奥鲁希奥延伸区域中，驱动空气通量的变化是如何变化的，以及（3）分析了范围的驾驶员，并分析了范围的驾驶员的驾驶员，并分析了跨性别的范围，并分析了范围的变化范围。并确定该变异性如何与较大的气候系统相关联。新的观察结果将在数十年来从船上观察到的更大背景以及近二十年的物理观察结果进行评估。收集到的数据将代表西方边界电流中的氧气，硝酸盐和衍生的DIC的第一个季节性解决方案，并将用于广泛的研究人员社区。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响评估标准来评估值得支持。