Characterizing meso- to submesoscale features in the South China Sea
Characterizing meso- to submesoscale features in the South China Sea
复制标题
表征南海中观到亚尺度特征
DOI：
10.1016/j.pocean.2020.102420
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发表时间：
2020-08
影响因子：
4.1
通讯作者：
Huang Yongxiang
中科院分区：
文献类型：
--
作者：
Lin Hongyang;Liu Zhiyu;Hu Jianyu;Menemenlis Dimitris;Huang Yongxiang
本文利用MITgcm llc 4320亚中尺度数值模式，在1/48°（南海约2.2km）的水平网格间距下，对南海的中尺度和亚中尺度特征进行了研究。模拟包括潮汐强迫，这是特别重要的，在南海的潮汐在区域动力学的许多方面发挥着关键作用。对观测结果的评价表明，模拟是能够再现广泛的动力学特征在南海。利用模拟结果分析了南海的中-次中尺度特征，主要发现如下：（1）南海具有丰富的次中尺度特征（2）南海大部分地区的正表面相对涡度（α）明显占主导地位，这可能是由于离心不稳定性的影响，但在气流与地形相互作用较强的地区也会出现较大的负α;（iii）南海上部的垂直运动主要受潮汐调制控制，其垂直速度高达0.01 m s− 1，比准平衡亚惯性运动的垂直速度大一个数量级;（iv）冬季和夏季动能的水平波数谱在波长低于100 km时的尺度大致为k− 2（k为水平波数）。此外，还重点分析了冬季南海北方、吕宋海峡、南海西边界流区和夏季越南东部等4个具有明显亚中尺度湍流特征的关键区域。注意到一些模式的不足之处，沿着建议，以提高模式的准确性，以更好地描述当地的次中尺度功能以及基本的动态。
In this study the mesoscale and submesoscale features in the South China Sea (SCS) are characterized based on a submesoscale-permitting numerical simulation (MITgcm llc4320) with nominal horizontal grid spacing of 1/48°(~ 2.2 km in the SCS). The simulation includes tidal forcing, which is particularly crucial in the SCS where tides play a key role in many aspects of regional dynamics. Evaluation against observations demonstrates that the simulation is capable of reproducing a wide spectrum of dynamical features in the SCS. The simulation is then used to characterize meso-to submesoscale features in the SCS and the key findings are summarized as follows:(i) the SCS is rich in submesoscale features (eg, vortices, filaments), which undergo significant seasonal variations in many regions;(ii) there is a clear dominance of positive surface relative vorticity (ζ) in most regions of the SCS presumably due to the centrifugal instability, but large negative ζ also emerges in areas with strong flow-topography interactions;(iii) the vertical motions in the upper SCS are dominated by tidal modulations with strong vertical velocities up to 0.01 m s− 1, about an order of magnitude larger than those due to the quasi-balanced sub-inertial motions; and (iv) both the wintertime and summertime horizontal wavenumber spectra of kinetic energy scale roughly as k− 2 (with k being the horizontal wavenumber) for wavelengths below 100 km. In addition, four key regions are highlighted with distinctive characteristics of submesoscale turbulence, including the northern SCS, Luzon Strait, the SCS western boundary current region in winter, and east of Vietnam in summer. A number of model deficiencies are noted, along with suggestions for improving model accuracy in order to better characterize the local submesoscale features as well as the underlying dynamics.
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影响因子：
16.6
作者：
Callies J;Ferrari R;Klymak JM;Gula J
通讯作者：
Gula J
影响因子：
3.5
作者：
Boccaletti, Giulio;Ferrari, Raffaele;Fox-Kemper, Baylor
通讯作者：
Fox-Kemper, Baylor
DOI：
10.1016/b978-0-12-409548-9.10828-0
发表时间：
2019
期刊：
Encyclopedia of Ocean Sciences
影响因子：
--
作者：
A. Mahadevan
通讯作者：
A. Mahadevan
影响因子：
3.5
作者：
D. Whitt;L. Thomas
通讯作者：
D. Whitt;L. Thomas
DOI：
10.1098/rspa.2000.0560
发表时间：
2000-05-08
影响因子：
3.5
作者：
Munk, W;Armi, L;Zachariasen, F
通讯作者：
Zachariasen, F