Submesoscale Ocean Fronts and Turbulence (SOFT) observatory

海洋锋面将不同温度和盐度的水域隔开，距离从几十公里到数百米不等，这一范围被称为亚中尺度。海洋表面布满了错综复杂的次中尺度锋面网络，具有每天10至100米的快速次表层垂直速度，比海洋其他地方强一个数量级。因此，它们可能在大气和海洋内部之间的热量和气体交换以及向发生光合作用的日光带提供营养物质方面发挥重要作用。然而，在可预见的未来，计算性能将不足以解决全球海洋模式中的亚中尺度问题。因此，我们必须开发出能够真实地再现次中尺度过程在已解决的较大尺度上的集体效应的参数。亚中尺度分辨率数值模拟现在在理想化或区域性环境中进行，但对亚中尺度过程的观测仍然很稀少。由于需要在大片区域以高分辨率对上层海洋的垂直和水平结构进行采样，因此从短期船载活动中获得了最详细的观测结果。缺乏长期的连续观测来提供大范围环境条件下亚中尺度动力学的统计观点。这项提议的目标之一是开始填补这一观察空白。作为第一步，下圣劳伦斯河口将在今后五年内提供一个天然实验室，利用高频雷达和系泊垂直剖面仪对次中尺度过程进行长期连续观测。这些观测旨在根据能够再现主要观测特征的最简单的动力学，指导发展次中尺度对较大尺度过程的累积影响的参数化。

Ocean fronts separate waters of different temperatures and salinities over distances ranging from a few tens of kilometers down to hundreds of meters, a range called submesoscale. The ocean surface is populated with a convoluted web of submesoscale fronts, featuring rapid subsurface vertical velocities of 10 to 100 meters per day, an order of magnitude stronger than in the rest of the ocean. They may therefore play an important part in the exchange of heat and gases between the atmosphere and the ocean interior, and in the supply of nutrients to the sun-lit zone where photosynthesis takes place. However, computing performances will not be sufficient for the foreseeable future to resolve submesoscales in global ocean models. We must therefore develop parameterizations that realistically reproduce the collective effect of submesoscale processes on the resolved larger scales. Submesoscale-resolving numerical simulations are now being run in idealized or regional settings, but observations of submesoscale processes have remained sparse. The most detailed observations have been obtained from short-term ship-borne campaigns, due to the necessity of sampling the vertical and horizontal structure of the upper ocean at high resolution over extended areas. There is a lack of long-term continuous observations to provide a statistical view of submesoscale dynamics in a wide range of environmental conditions. One of the goals of this proposal is to start filling this observational void. As a first step, in the next five years, the Lower St-Lawrence Estuary will provide a natural laboratory to acquire long-term continuous observations of submesoscale processes, using high-frequency radars and moored vertical profilers. These observations are intended to guide the development of parameterizations of the cumulative effects of submesoscale on larger-scale processes, based on the simplest dynamics able to reproduce the main observed features.