The turbulent dynamics of shoaling internal waves

加拿大的淡水资源是经济和娱乐活动的一个关键要素，尽管资源丰富，但正受到威胁。 人们只需要思考沃克顿的污染水，马尼托巴和魁北克的巨大洪水，渔业的崩溃，斑马贻贝的殖民化以及Love Canal等工业场所的毒素，就可以意识到我们的经济活动和对水的需求如何对加拿大自然水生系统的可持续性产生不利影响。 管理这些资源的一个重要工具是结合了水动力学和水质的计算机模型，该模型具有独特的诊断和预测模拟能力。 这些模型的准确性受到必须重现一系列相互关联的复杂环境流的限制，例如墨西哥湾流超过1000公里，破碎波超过米，湍流混合超过毫米。 因此，有必要了解在这些尺度上发生的基本过程。 本研究的目的是调查这些过程之一-变浅和破碎的内波-使用受控的实验室实验和理想化的计算机模拟。 内波形成于分层水体（如湖泊、大气层和海洋）的表面之下，与其表面对应物一样，它们在倾斜的地形上破裂。 破碎的内波局部地混合分层层，这通常抑制流体的垂直输送。 这一过程具有重大意义，从调节水生生物化学到控制影响全球海洋气候的大规模环流模式。 将为一名博士生和四名硕士生提供物理建模、图像分析和计算机模拟应用方面的专门培训，以首次详细研究与斜坡地形上内波破碎有关的三维动力学和混合过程。 最终目标是在用于管理加拿大内陆和沿海水资源的计算机模型中更好地代表这些过程。

Despite their abundance, Canada's fresh water resources, a key element for economic and recreational activities, are being threatened.  One must only ponder the contaminated water in Walkerton, the immense flooding in Manitoba and Québec, the collapse of fisheries, the colonization by the zebra mussel and the leaching toxins from industrial sites such as the Love Canal, to realize how our economic activities and demand for water are adversely impacting the sustainability of Canada's natural aquatic systems.  A vital tool in the management of these resources is the combined hydrodynamic and water-quality computer model, which is uniquely capable of running both diagnostic and predictive simulations.  The accuracy of these models is limited by the necessity to reproduce a range of interconnected complex environmental flows, e.g. the Gulf Stream occurring over 1000s of kilometres, breaking waves occurring over meters and turbulent mixing occurring over millimetres.  Consequently, it is necessary to understand the basic processes occurring at each of these scales.  The objective of this study is to investigate one of these processes - the shoaling and breaking of internal waves - using controlled laboratory experiments and idealized computer simulations.  Internal waves form below the surface of stratified waterbodies (e.g. lakes, atmospheres and oceans), and like their surface counterparts, they break upon sloping topography.  Breaking internal waves locally mix the stratifying layers, which normally inhibit vertical transport of fluid.  This process has significant implications ranging from regulating the aquatic bio-chemistry to controlling large-scale circulation patterns that influence the global-ocean climate.  Specialized training will be provided for one Doctoral and four Master's students in the application of physical modelling, image analysis and computer simulations to perform the first ever detailed study of the three-dimensional dynamics and mixing processes associated with internal wave breaking on sloping topography.  The ultimate objective being to better represent these processes in the computer models used to manage Canada's inland and coastal water resources.