Collaborative Research: Investigating the Air-Sea Energy Exchange in the presence of Surface Gravity Waves by Measurements of Turbulence Dissipation, Production and Transport

了解海气边界层过程需要对海洋中的混合和输送进行定量描述。海洋模式的发展和改进依赖于捕获与从大气到海洋的能量转移有关的中、小尺度湍流的综合观测项目的结果。在这个项目中，通过一套独特的湍流测量将大气和海洋联系起来，研究了表面重力波在能量传递中的作用。这些是在空气和水两侧同时进行的。为了阐明海气波驱动的湍流，研究小组将在玛莎葡萄园岛海岸天文台的海气相互作用塔上测量海气界面上的湍流动能耗散率的垂直结构。提出的湍流测量将增强对耦合边界层动力学的理解，并将改进现有和未来的海气相互作用参数化。实地活动还将为社区创建一个数据集，我们将通过开放访问数据系统共享这些数据集。这将加速高分辨率波浪耦合海洋数值模式的发展，并改善天气和海洋状况预报。通过教育进行外展也是这个项目的一个重点。除了支持和培训一名研究生和一名博士后研究员外，将通过现有的NSF-REU计划（URI）和与当地学校的新合作提供本科生研究经验（REU），以使高中生接触地球科学（康涅狄格大学）。这项研究的重点是从大气到海洋的能量转移以及这种转移如何在海气界面上发生。对大气侧能量通量散度（波致输运）的间接和直接观测将用于约束气-海TKE传输速率的大小，并为破波（即破波功）注入的TKE提供上限。对海洋表面的主动断裂和由此产生的泡沫的直接估计将用于提供对地下TKE耗散率的补充估计。在海洋一侧，将使用几种互补技术测量整个水柱的TKE耗散率和TKE产生和输送项。利用这些测量结果，研究人员将探索相对于刚性壁面的预期TKE耗散率赤字/盈余，并评估表面重力波在偏差中的作用。此外，将尝试阐明和区分波浪破碎和Langmuir环流驱动的湍流的影响，并定义特征湍流尺度，以改进现在和未来上层海洋的混合参数化。在大气方面，对壁律的偏离预计与能量通量发散有关，而能量通量发散是由波动在波场中产生能量通量引起的。该研究将表征大气侧空气速度和压力的波特征，进一步阐明能量交换的物理特性。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Understanding of air-sea boundary layer processes requires a quantitative description of mixing and transport in the ocean. The development and improvement of ocean models rely on results from comprehensive observation programs that capture mid- to small-scale turbulence which is associated with energy transfer from the atmosphere to the ocean. In this project, the role of surface gravity waves in energy transfer is studied by linking the atmosphere and ocean through a unique set of turbulence measurements. These are carried out simultaneously both on the air and water sides. To elucidate air-sea wave driven turbulence, the research teams will measure the vertical structure of the turbulence kinetic energy (TKE) dissipation rate across the air-sea interface from the Air Sea Interaction Tower at Martha's Vineyard Coastal Observatory. The proposed measurements of turbulence will enhance the understanding of coupled boundary layer dynamics and will improve existing and future air-sea interaction parameterizations. The field campaign will also create a data set for the community that we will be shared through an open-access data system. This will accelerate the development of high-resolution wave coupled ocean numerical models and improve both weather and ocean conditions forecasts. Outreach through education is also a focus of this program. In addition to the support and training of a graduate student and a post-doctoral researcher, undergraduate research experiences (REU) will be provided through an existing NSF-REU program (URI) and new collaborations with local schools to expose high school students to earth sciences (UConn).This study focuses on the energy transfer from the atmosphere to the ocean and how this occurs across the air-sea interface. Indirect and direct observations of the energy flux divergence (wave-induced transport) on the atmospheric side will be used to constrain the magnitude of the air-sea TKE transfer rate and to provide an upper bound to the TKE injection by wave breaking (i.e. the breaker work). Direct estimates of active breaking and the resulting foam on the ocean surface will be used to provide complementary estimates of the subsurface TKE dissipation rate. On the ocean side, measurements of TKE dissipation rate and the TKE production and transport terms throughout the water column will be made using several complementary techniques. Using these measurements, the researchers will explore the expected TKE dissipation rate deficit/surplus at the interface relative to a rigid wall and assess the role of surface gravity waves in the deviations. Furthermore, an attempt will be made to elucidate and differentiate the effects of wave breaking and Langmuir Circulation driven turbulence and define characteristic turbulent scales to improve present and future mixing parameterizations in the upper ocean. On the atmospheric side, deviations from the law-of-the-wall are expected to be correlated to the energy flux divergence, which arises from wave motion creating an energy flux into the wave field. This study will characterize the wave signature on the air velocities and pressure on the atmospheric side, further elucidating the physics of the energy exchange.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.