Coastal and Continental Shelf Oceanography

沿海和大陆架海洋学

• 批准号: RGPIN-2017-05157
• 负责人: Hay, Alex
• 金额: $ 1.97万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711418
• 关键词: Coastal; Continental; Shelf; Oceanography

OBJECTIVES: The long-term goal is improved predictions for the dynamic adjustment of mobile beds to combined wave-current forcing in nearshore and continental shelf environments. The primary short term goal is to pursue the use and development of advanced acoustic remote sensing systems for investigating the turbulent fluxes of momentum and sediment in the bottom boundary layer under active transport conditions, and the extreme value statistics of turbulence in high-flow tidal channels. APPROACH: (1) A state-of-the art, high-resolution, turbulence-resolving, multi-frequency acoustic Doppler profiling system developed in-house will be used in laboratory and field experiments to remotely measure the space-time structure of velocity, turbulence and sediment flux above evolving mobile beds. (2) The variability of turbulence on 1-second to 1-month time scales will be investigated at mid-depth in high-flow tidal channels both directly, using in situ fast-response turbulence probes, and remotely, using multiple advanced acoustic Doppler systems. (3) Mobile bed adjustment to wave-current forcing in the nearshore zone and inner continental shelf during storms, and adjustment of dunes and mega-dunes to the intense turbulence and reversing current conditions in high-flow tidal channels, will be investigated using an instrumented robotic surface vehicle. SIGNIFICANCE: The adjustment of mobile seabed sediments to fluid forcing variability is one of the important challenges in modern ocean science. The importance resides in: (A) the applied science and societal needs for more accurate predictions of seabed change related to shoreline and coastal infrastructure protection traditionally, and now including the effects of seabed stability on the potential development of high-flow tidal channels for renewable hydroelectric power generation using in-stream turbines; (B) the effects of turbulence and seabed adjustment on the predictability of coastal and shelf-wide environmental conditions, and (C) in the potential for improved interpretation of paleo-environmental conditions through the sedimentary record. The challenges reside in: (1) the observational difficulties, (2) in the responses of the mobile sediments and the motion of the overlying fluid being both mutual and non-linear, and (3) in the fundamental connections to fluid turbulence, one of the great unsolved problems in classical physics.

目的：长期目标是改进的预测，以对移动床的动态调整，以在近岸和大陆架环境中组合波流强迫的组合。主要的短期目标是追求和开发高级声学遥感系统，以调查在主动传输条件下底部边界层中动量和沉积物的湍流，以及高流量潮汐通道中湍流的极端价值统计。 方法：（1）在实验室和现场实验中开发的最先进的，高分辨率，解决湍流，湍流，多频听音多普勒分析系统将用于内部，以远程测量速度，湍流和沉积物的速度，湍流和沉积物的时空结构。 （2）使用原位快速响应湍流探针，使用多个高级声音多普勒系统，将在高流量潮汐通道中直接研究1秒至1个月尺度的湍流直接在高流量潮汐通道中进行研究。 （3）在风暴期间，移动床调整了近岸区域和内部大陆架的波电流强迫，并将使用仪器的机器人地面车辆调查，将沙丘和大型杜松调整为高流量潮汐通道的强烈湍流和逆转当前状况。 意义：将移动海床沉积物调整为流体强迫变异性是现代海洋科学的重要挑战之一。重要性在于：（a）应用科学和社会需求，以更准确地预测与海岸线和沿海基础设施相关的海床变化，现在包括海床稳定性对使用Intream Trunsine Intream Truntine intream Trustine的可再生水力发电的高流量潮汐通道潜在发展的影响； （b）湍流和海床调节对沿海和整个环境条件的可预测性的影响，以及（c）通过沉积记录改善对古环境条件的解释的潜力。挑战存在：（1）观察性困难，（2）移动沉积物的响应以及上覆的流体的运动是相互和非线性的，以及（3）在与流体湍流的基本联系中，这是经典物理学中最大的未解决问题之一。