Large Eddy Simulation of Shelf Sea Thermocline Mixing Processes

大陆架海提供了河口和海洋之间的过渡带，碳、营养物、沉积物和污染物通过该过渡带进行交换。虽然大陆架上的海流和混合主要是由潮汐与海床相互作用，但在夏季的几个月里，生物初级生产的水平很高。营养物质和碳在分层流体的这些关键界面上的交换知之甚少，在数值模型中也代表性不足。目前的建议旨在利用最先进的计算机建模和分析工具，调查和量化的物理机制和过程，负责通过这一关键界面的通量。特别是，重点将是了解在潮汐强陆架海洋环境中混合层湍流和风驱动的惯性振荡之间的相互作用。假设这些在温跃层的相互作用将超过临界剪切阈值，导致灾难性的稳定性损失和幕式混合。将开发这种混合的参数化。然后将通过观察进入季节性温跃层的营养通量来调查对陆架海生态系统的潜在影响。

The continental shelf seas provide a transistion zone between estuaries and the ocean across which carbon, nutrients, sediments and contaminants are exchanged. Whilst the currents and mixing on the continental shelf are dominated by the tide interacting with the sea bed, significant levels of biological primary production occurs in regions that stratify during the summer months. The exchange of nutrients and carbon across these critical interfaces of stratified fluid is poorly understood and is also underrepresented in numerical models. The current proposal aims to exploit state-of-the-art computer modelling and analysis tools in the investigation and quantification of the physical mechanisms and processes responsible for the fluxes across this critical interface. In particular the focus will be on understanding the interaction between mixed layer turbulence and wind-driven inertial oscillations in the tidally-strong shelf sea environment. The hypothesis is that these interactions at the thermocline will exceed a critical shear threshold leading to catastrophic loss of stability and episodic mixing. Parameterisations for this mixing will be developed. The potential impact on the shelf sea ecosystem will then be investigated by looking at the nutrient flux into the seasonal thermocline.