COLLABORATIVE RESEARCH: Observing and characterizing submesoscale dynamics in the Arctic Ocean

初步分析表明，北冰洋混合层表现出复杂的亚中尺度结构，具有显著的水平密度梯度（锋面）和直径几公里或更小的小涡流，这些特征是北冰洋大尺度数值模式无法解决的。为探索亚中尺度过程在调节北极大气、海冰、海洋表面混合层和深层海洋之间具有重要气候意义的相互作用中的作用提供了资金；一系列重要的科学问题将得到解决：北冰洋混合层亚中尺度水平密度变化的主要特征是什么？混合层的亚中尺度动力学与混合层深度和分层有什么关系？是什么机制导致了混合层中水平密度的变化？与亚中尺度过程相关的垂直运动是什么？它们如何影响混合层之间的交换？pi计划通过有针对性的实地实验，同时分析最近的海洋（温度、盐度和速度）和海冰测量，以及指导的动态过程研究，来研究表面海洋动力学和热力学的这些方面。由于亚中尺度过程发生在空间尺度上，而现有的北冰洋模式并不能明确地解决这一问题，因此必须对其影响进行参数化，以便准确地预测海洋的动力和混合环境。为了适当地参数化这些过程，首先有必要了解它们与海洋大尺度结构和动力学的关系。这项工作将提供基础知识，从而允许将来对模型进行改进。

Preliminary analysis reveals that the Arctic Ocean mixed layer displays a complicated submesoscale structure with significant horizontal density gradients (fronts) and small eddies a few kilometers, or less, in diameter - features that are not resolvedby large-scale numerical models of the Arctic Ocean. Funds are provided to explore the role of submesoscale processes in regulating the climatically-important interactions among the Arctic atmosphere, sea-ice, ocean surface mixed layer and the underlying deeper ocean; a set of essential scientific questions will be addressed: What are the dominant characteristics of submesoscale horizontal density variability in the Arctic Ocean mixed layer? How do submesoscale dynamics in the mixed layer relate to mixed-layer depth and stratification? What mechanisms are responsible for the horizontal density variability in the mixed layer? What vertical motions are associated with submesoscale processes and how do they impact exchanges across the mixed layer? The PIs intend to investigate these aspects of the surface ocean dynamics and thermodynamics by a targeted field experiment accompanied by analysis of recent ocean (temperature, salinity and velocity) and sea-ice measurements, and directed dynamic process studies.Because submesoscale processes occur on spatial scales that are not explicitly resolved by existing models of the Arctic Ocean, their effects must be parameterized in order to accurately predict the dynamics and mixing environment of the ocean. In order to appropriately parameterize these processes, it is first necessary to understand how they are related to the large scale structure and dynamics of the ocean. This work will provide that basic knowledge, thus allowing future improvements to the models.