Ocean Energetics, Tidal Conversion and Baroclinic Instability

海洋能量学、潮汐转换和斜压不稳定威廉·杨·斯克里普斯海洋研究所该项目旨在了解海洋能量学、混合、斜压不稳定、潮汐转换和温跃层的形成。该项目的第一部分是了解限制对海洋能量学的影响和扩展。由于海洋中没有深层浮力来源(除了小的地热加热)，人们可以证明，在统计上稳定的状态下，在每个深度的动能和势能之间没有交换。粘性动能的耗散完全由潮汐和风的强迫来平衡；在海洋中基本上不存在将势能转化为动能的净过程。理论将发展并针对Boussinesq能量学以及海洋中可用势能和背景势能的平衡进行分析。第二个目标将是使用原始方程模拟和理论来研究斜压涡旋在海洋温跃层形成中的作用。这将检验这样一种假设，即与破裂的内部重力波相关的浮力通量被斜压涡流平衡。还将发展和实施准地转近似的扩展，其中背景层结是自洽确定的，而不是简单地规定的。第三个目标将是改进对浮力频率强烈变化的海洋中实际大地形产生内潮的计算。解的一种新的边界积分表示法导出了一个积分方程式，使得能够有效地计算由地形产生的重力内波。这些目标涉及通过基于能量平衡的物理论证，确定海洋混合和湍流在决定地球气候长期变化方面的关键作用。

Ocean energetics, tidal conversion and baroclinic instabilityWilliam YoungScripps Institute of OceanographyThe project is directed at understanding ocean energetics, mixing, baroclinic instability, tidal conversion, and the formation of the thermocline. The first part of the project is understanding the ramifications and extensions of constraints on the ocean energetics. Because there are no deep sources of buoyancy in the ocean (apart from small geothermal heating), one can show that in a statistically steady state there is no exchange between the reservoirs of kinetic and potential energy at every depth. The viscous dissipation of kinetic energy is balanced totally by tidal and wind forcing; there is essentially no net transformation o f potential into kinetic energy in the ocean. Theory will be developed and directed at analyzing Boussinesq energetics and the balances of available and background potential energies in the ocean. A second goal will be use primitive equation simulations and theory to examine the role of baroclinic eddies in forming the ocean thermocline. This will test the hypothesis that buoyancy flux associated with breaking internal gravity waves is balanced by baroclinic eddies. An extension of the quasi-geostrophic approximation, in which the background stratification is self-consistently determined, rather than simply prescribed, will also be developed and implemented numerically. The third goal will be an improved calculation of the generation of the internal tide by realistically large topography in an ocean with strongly variable buoyancy frequency. A new boundary-integral representation of the solution leads to an integral equation that enables efficient calculation of the internal gravity waves generated by topography. These goals relate to establishing the critical role of ocean mixing and turbulence in determining long-term changes in the Earth's climate via physical arguments based on energy balances.