Collaborative Research: Evaluating mechanisms for enhanced mixing below tropical instability waves

该项目支持热带太平洋的海洋学实地活动，根据系泊和船舶的海洋速度、密度和微结构进行高时间和空间分辨率的测量。为了更好地了解热带不稳定波(TIW)对海洋内波混合和调制的影响，将对热带不稳定波(TIW)存在时向西传播的海洋锋进行观测。这项拟议的工作对于理解厄尔尼诺南方涛动(ENSO)和热带海洋在气候中的作用具有重要意义。该项目的教育和推广将包括指导一名研究生和博士后，在当地高中进行科学演讲，本科生实习生研究经验指导，以及参与海洋发现研究所的家庭作业援助计划。该项目研究赤道太平洋TIW观测到的内波调制和湍流混合的动态过程，以及对热量调节和ENSO可预报性的潜在影响。需要研究的机制包括TIW对向下传播的内波的辐射，TIW对内波场的调制，以及临界层存在时内波的去向。观测活动将使用系泊设备、船载声学、舰载剖面系统，包括快速剖面CTD(FastCTD)和湍流剖面仪(Epsileter)，以及三台自主漂流波浪动力剖面仪(WireWalkers)。在运行中的140°W热带大气海洋(TAO)系泊设施以北一年内，将部署三个系泊设备，以针对内波和混合的TIW调制中的季节性周期。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project supports an oceanographic field campaign in the tropical Pacific to make high temporal and spatial resolution measurements from moorings and ship of the oceanic velocity, density, and microstructure. Observations will be made of westward propagating oceanic fronts in the presence of Tropical Instability Waves (TIW) to better understand their influence on mixing and modulation of oceanic internal waves. The proposed work has important implications for understanding the El Nino Southern Oscillation (ENSO) and the role of the tropical oceans in climate. Education and outreach for this project will include mentoring a graduate student and postdoc, science presentations at local high schools, mentorship for Research Experience for Undergraduates (REU) interns, and participation in the Ocean Discovery Institute homework assistance program.This project addresses the dynamic processes that govern the observed modulation of internal waves, and turbulent mixing, by TIWs in the equatorial Pacific and the potential effects on heat regulation and ENSO predictability. Mechanisms to be studied include radiation of downward propagating internal waves from TIWs, modulation of the internal wave field by TIWs, and the fate of the internal waves in the presence of critical layers. The observational campaign will employ moorings, ship-mounted acoustics, ship-based profiling systems including a rapid profiling CTD (fastCTD) and a turbulence profiler (Epsilometer), and three autonomous drifting wave-powered profilers (WireWalkers). Three moorings will be deployed for a year north of the operational 140°W Tropical Atmosphere Ocean (TAO) mooring to target the seasonal cycle in the TIW modulation of internal waves and mixing.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.