Fundamentals of the Oceanic Eddy Backscatter

模拟大尺度流动的综合海洋环流模式必须考虑小尺度湍流的影响，而这些影响不能用数值方法解决。这些效应是非线性的，因此很难捕捉到。本项目将重点研究中尺度涡旋如何与大尺度相互作用，特别是涡旋场的随机性和瞬时性对平均流动的影响。要解决的中心问题是这些相互作用如何产生大范围的电流。在海洋中，这一过程无处不在。在这个项目中，伍兹霍尔海洋研究所的一位科学家将把这些涡流效应视为随机过程。这项提议的主要目标是对这些随机强迫反应背后的机制有一个物理上的了解。特别是，这将使他能够考虑环流模型中常用的涡流粘性不能处理的“上梯度”通量。这一新的方法带有风险因素，它不会成功。这项研究可能会产生非常重要的更广泛的影响，因为它将为海洋环流模型中的湍流参数化的新方法提供物理基础，从而改善气候模型的性能。

Comprehensive ocean general circulation models that simulate large scale flows must incorporate the effects of smaller scale turbulence that cannot be resolved numerically. These effects are nonlinear and thus are difficult to capture. This project will focus on how mesoscale eddies interact with the large scale and in particular what the effect of randomness and transience of the eddy field is on the mean flow. The central problem that will be tackled is how large scale currents are generated by these interactions. In the ocean, this process is ubiquitous. In this project, a scientist from Woods Hole Oceanographic Institution will treat these eddy effects as stochastic processes. The primary objective of this proposal is to gain a physical understanding of the mechanics behind the response of these stochastic forcings. In particular, this will allow him to consider "up gradient" fluxes which can not be handled by eddy viscosities, which are commonly used in circulation models. This novel approach carries an element of risk that it will not be successful.The study potentially has very important broader impacts because it will provide a physical basis for a new means of parameterizing turbulence in ocean circulation models and thus climate models which should improve their performance.