Collaborative Research: Influence of wind and bottom generated turbulence on air-sea gas exchange in shallow water environments

合作研究：风和底部产生的湍流对浅水环境中海气交换的影响

• 批准号: 1829911
• 负责人: David Ho
• 金额: $ 28.28万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-10-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829911&HistoricalAwards=false
• 关键词: Collaborative; Research; Influence; wind; bottom

Air-sea transfers of energy and gases are critically important for predictions of short term weather, as well as long term climate trends. Over the past decades, considerable effort has been devoted to parameterizing these fluxes in terms of widely measured variables such as wind speed. However, these parameterizations are inadequate in shallow coastal regions where fetch, waves, and bottom-generated turbulence influence the physical mechanisms responsible for the air-sea fluxes, which have implications for our ability to understand important environmental processes such as coral reef metabolism or carbon cycling. Furthermore, shallow coastal water ecosystems are susceptible to anthropogenic pollution, leading to hypoxia or anoxia. In order to understand the future states of these ecosystems that are exposed to continued anthropogenic perturbations, biogeochemical budgets and fluxes have to be established, including exchanges across the air-water interface, i.e., they require quantitative knowledge of factors controlling gas exchange. This project will measure the air-sea gas fluxes and multiple physical variables contributing to their variability in a shallow coral reef. It is anticipated that the results from this study will yield improved understanding of the influence of physical processes such as wind, currents, waves on producing surface-, and bottom-driven turbulence, and how they control air-sea gas exchange in shallow coastal waters. They should also allow these processes to be parameterized in terms of easily measured environmental variables such as wind speeds, current velocities, and water depth. On a more local level, the PIs will continue their efforts toward disseminating scientific understanding in the field of physical and chemical oceanography by participating in undergraduate research opportunities, local science events targeted at K-12 students, and graduate student advising. This project will provide multidisciplinary training to two graduate students, and an undergraduate student.A series of experiments will be performed over two consecutive years on the barrier reef of Kane'ohe Bay, Hawaii to determine factors that control gas exchange in shallow ocean environments. During the experiment, gas transfer velocities will be measured with tracers (N2O, SF6, Rhodamine WT) and eddy covariance of CO2, along with concurrent measurements of processes such as wind, current, waves and turbulence. With the data collected in Kane'ohe Bay, the PIs will: (i) Assess when or whether it is valid to apply open ocean wind speed/gas exchange parameterizations toshallow water environments (ii) Improve our understanding of how physical processes such as wind, currents, waves interact with the shallow bottom to produce surface-, and bottom-driven turbulence (iii) Examine how surface and bottom generated turbulence control air-sea gas exchange in shallow coastal waters (iv) Parameterize gas exchange in shallow water environments in terms of easily measured environmental variables such as wind speeds, current velocities, and water depth.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.

能源和气体的空气传输对于预测短期天气以及长期气候趋势至关重要。在过去的几十年中，已经大量努力以广泛测量的变量（例如风速）来参数化这些通量。但是，这些参数化在浅层沿海区域不足，在这些沿海区域中提取，波浪和底部产生的湍流会影响负责空气通量的物理机制，这对我们理解重要环境过程（例如珊瑚礁代谢代谢或碳循环）的能力有影响。此外，浅水沿海水生态系统易受人为污染的影响，导致缺氧或缺氧。为了了解这些生态系统的未来状态，这些状态可能会持续人为扰动，必须建立生物地球化学预算和通量，包括在空气水界面之间进行交流，即，它们需要对控制气体交换的因素进行定量了解。该项目将测量空气气体通量和多个物理变量，导致它们在浅珊瑚礁中的变异性。预计这项研究的结果将提高人们对诸如风，电流，波浪对产生表面和底部驱动湍流等物理过程影响的影响，以及它们如何控制浅水沿海水域中的气海气交换。它们还应允许这些过程以易于测量的环境变量（例如风速，电流速度和水深度）进行参数化。在更新的地方，PI将继续努力通过参与本科研究机会，针对K-12学生的本地科学活动以及研究生咨询，以传播物理和化学海洋学领域的科学理解。该项目将为两名研究生提供多学科的培训，并在本科生中提供多学科的培训。将在夏威夷Kane'ohe Bay的障碍礁连续两年内进行一系列实验，以确定控制浅海环境中天然气交换的因素。在实验过程中，将使用示踪剂（N2O，SF6，Rhodamine WT）和CO2的涡流协方差，以及对风，电流，波浪和湍流等过程的同时测量。随着在Kane'ohe湾收集的数据，PI将：（i）评估何时或使用开放海洋风速/气体交换参数toshallow水环境（ii）提高我们对诸如风能，电流，波浪等物理过程的理解，波浪与浅层底部相互作用，以产生表面和底部驱动的速度和沿沿沿沿沿沿层的速度（II II），以检查沿沿岸的速度（III II II II II II II II）从浅水环境中的参数化气体交换就易于测量的环境变量（例如风速，当前速度和水深度）而言。该奖项反映了NSF的法定任务，并被认为值得通过基金会的知识分子优点和更广泛的影响来通过评估来进行评估。