Abstract Despite the recent success achieved by the unstructured-grid SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) in multi-resolution studies, its skill in simulating the baroclinic eddying ocean needs to be further improved. In particular, the classical 2nd-order transport schemes for estuaries and coastal zones are too dissipative to resolve the baroclinic dynamics associated with strong boundary currents, such as meso-scale meanders and eddies. To close this gap, this paper presents a newly designed 3rd-order finite volume transport scheme, based on the Weighted Essentially Non-Oscillatory (WENO) formalism. This new scheme strikes a delicate balance among accuracy, efficiency, and monotonicity for the transport in the eddying regime. Idealized numerical benchmark experiments demonstrate that the WENO scheme is very effective in limiting numerical diffusion. The scheme is then applied in a realistic simulation of the Gulf Stream and the surrounding circulation, further confirming its capability of resolving baroclinic meso-scale eddies and meanders. This new high-order transport scheme is therefore ideal for extending the ability of SCHISM to study cross-scale baroclinic applications that range from the river dynamics to the eddying ocean processes.

中文翻译：

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用于在非结构化网格上模拟斜压涡旋海洋的三阶 WENO 传输方案

摘要 尽管非结构化网格 SCHISM（半隐式跨尺度水文综合系统模型）最近在多分辨率研究中取得了成功，但其模拟斜压涡旋海洋的能力还需要进一步提高。特别是，河口和沿海地区的经典二阶运输方案太耗散，无法解决与强边界流相关的斜压动力学，例如中尺度曲流和涡流。为了弥补这一差距，本文提出了一种新设计的基于加权基本非振荡 (WENO) 形式主义的三阶有限体积传输方案。这种新方案在涡流状态下的传输的准确性、效率和单调性之间取得了微妙的平衡。理想化的数值基准实验表明 WENO 方案在限制数值扩散方面非常有效。然后将该方案应用于墨西哥湾流和周围环流的真实模拟，进一步证实了其解决斜压中尺度涡流和曲流的能力。因此，这种新的高阶传输方案非常适合扩展 SCHISM 研究从河流动力学到涡旋海洋过程的跨尺度斜压应用的能力。