Near-inertial Wave Generation, Propagation and Mixing in the East Pacific Warm Pool

0424792智力成果：将利用东太平洋气候调查（EPIC2001）密集实地调查期间收集的数据来进行与近惯性内波相关的产生、传播和上层海洋混合。这项工作将增进我们对低纬度地区近惯性波的产生、传播和衰变过程的理解，尽管鉴于最近对近惯性波混合对全球混合预算的贡献的估计，这些过程可能很重要，但人们对此知之甚少。混合层惯性运动的风通量图也表明东太平洋暖池（EPWP）可能是低纬度惯性波产生的热点。初步研究结果表明，近惯性波产生的混合可能会影响混合层底部的夹带以及该区域浅温跃层的结构和演化。 EPIC2001 调查的时间序列和空间数据都表明，温跃层内的剪切力和湍流主要由单一的、充满活力的、向下传播的近惯性内波主导。 EPIC2001 数据集的丰富性以及来自多个平台的上层海洋和下层大气的时空采样，为进行此类调查提供了独特的机会。先前对低纬度近惯性波的研究缺乏空间数据来扩展粗略估计之外的传播和产生细节。该项目的主要科学目标是： 1．在时间和空间上量化和描述近惯性波并混合它在 10?N, 95?W.2 处产生。确定波对混合层性能的影响。3．利用线性波理论估计波的特性。4．量化波的能量通量并估计传播和湍流耗散的损失。5．使用简单的混合层板模型研究风强迫的时空变化。6．利用风力原方程数值模型研究波浪的产生和传播。7．将我们的结果与过去的近惯性波研究和线性近惯性波理论的结果进行比较。更广泛的影响：这项研究将与其他 EPIC2001 研究人员密切合作进行，有助于更好地理解 EPWP 和热带辐合带 (ITCZ) 中的大气-海洋耦合的 EPIC 目标。研究结果还将为改进海洋模型中混合层湍流通量的参数化提供物理基础，该模型用于预测关键气候区域的混合层深度和热含量。作为该项目的一部分，一名研究生将完成他的博士学位。使用现代分析和建模工具将海洋湍流数据解释为上层海洋对大气强迫响应的一部分的培训。

0424792Intellectual Merit: The generation, propagation and upper-ocean mixing associated with near inertial internal waves will be conducted using data collected during the Eastern Pacific Investigation of Climate(EPIC2001) intensive field survey. This work will advance our understanding of near-inertial wave generation, propagation and decay at low-latitudes-processes that are poorly understood though likely important in light of recent estimates of the contribution of near-inertial wave mixing to the global mixing budget. Maps of wind-flux into mixed-layer inertial motions also indicate that the Eastern pacific Warm Pool (EPWP) may be a hotspot for low-latitude inertial wave generation. Preliminary findings suggest that near-inertial wave-produced mixing may influence entrainment at the base of the mixed-layer and the structure and evolution of the region's shallow thermocline. Both time series and spatial data from the EPIC2001 survey show that shear and turbulence within the thermocline were dominated by a single, energetic, downward-propagating near-inertial internal wave. The richness of the EPIC2001 data set, with temporal and spatial sampling of the upper ocean and lower atmosphere from a number of platforms, presents the unique opportunity to conduct such an investigation. Previous studies of low-latitude near-inertial waves lacked spatial data to extend the propagation and generation details beyond rough estimation.The main scientific objectives of the project are to:1. Quantify and describe in time and space the near-inertial wave and mixing it produced at 10?N, 95?W.2. Determine the influence of the wave on mixed-layer properties.3. Estimate the wave's properties using linear wave theory.4. Quantify the wave's energy flux and estimate losses to spreading and turbulent dissipation.5. Use a simple mixed-layer slab model to investigate the temporal and spatial variability of wind forcing.6. Use a wind-forced primitive equation numerical model to investigate the wave's generation and propagation.7. Compare our results with those of past near-inertial wave research and linear near-inertial wave theory.Broader Impacts: This research will be done in close interaction with other EPIC2001 investigators and contribute to the EPIC goal of better understanding atmosphere-ocean coupling in the EPWP and Intertropical Convergence Zone (ITCZ). The results will also provide a physical basis for improving parameterizations of mixed-layer turbulent fluxes in ocean models utilized for making predictions of mixed-layer depth and heat-content in a key climatic region. As part of the project, a graduate student will complete his Ph.D. training in interpreting oceanic turbulence data as part of the upper ocean response to atmospheric forcing using modern analysis and modeling tools.