Seasonal thermal fronts on the northern South China Sea shelf: Satellite measurements and three repeated field surveys
Seasonal thermal fronts on the northern South China Sea shelf: Satellite measurements and three repeated field surveys
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南海北部陆架季节性热锋：卫星测量和三次重复实地调查
DOI：
10.1002/2015jc011222
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发表时间：
2016-03
影响因子：
3.6
通讯作者：
Shumin Lian
中科院分区：
文献类型：
--
作者：
Zhiyou Jing;Yiquan Qi;Baylor Fox-Kemper;Yan Du;Shumin Lian
利用卫星观测资料和三次高分辨率地形测绘资料，对南海北方海域冬、春、夏三季与风驱动的沿岸上升流/下降流相关的季节性热力锋进行了研究。结果表明，在不同季节，陆架上有不同宽度和强度的强热锋，其宽度和强度与20-100 m等深线大致一致。在盛行的冬/夏季风的驱动下，观测到次表层强度超过0.1 ℃/km的带状锋，并伴随着由于向岸/离岸Ekman输送而产生的充满活力的沿海下降流/上升流。整个大陆架的季节性温跃层的向下/向上倾斜超过20米，显著地促进了大陆架上热锋的发展。此外，位涡诊断分析表明，与有利于下沉的季风强迫相关的冬季锋相比，由沿岸上升流引起的夏季锋活动对对流和对称不稳定更为稳定。这主要是由于它们在上层海洋分层和风强迫引起的水平浮力梯度方面的根本差异。与此同时，沿岸流基本上受季节性风的调节。在锋面区域附近检测到系泊测量的速度和沿岸风应力之间的预期滞后相关性。这些结果表明，季节风强迫在锋面活动和陆架沿岸水输送中起着重要的作用。
Seasonal thermal fronts associated with wind-driven coastal downwelling/upwelling in the northern South China Sea are investigated using satellite measurements and three repeated fine-resolution mapping surveys in winter, spring, and summer. The results show that vigorous thermal fronts develop over the broad shelf with variable widths and intensities in different seasons, which tend to be approximately aligned with the 20-100 m isobaths. Driven by the prevailing winter/summer monsoon, the band-shaped fronts were observed with a magnitude exceeding 0.1 degrees C/km in the subsurface, and accompanied by energetic coastal downwelling/upwelling due to shoreward/offshore Ekman transport. The downward/upward tilting of seasonal thermoclines across the shelf exceeds 20 m, significantly contributing to the development of thermal fronts over the shelf. In addition, the diagnostic analysis of Potential Vorticity (PV) suggests that the summer frontal activities induced by the coastal upwelling are more stable to convection and symmetric instabilities in comparison to the winter fronts associated with downwelling-favorable monsoon forcing. This is primarily due to their essential differences in the upper ocean stratification and horizontal buoyancy gradients arising from wind forcing. At the same time, the coastal currents are substantially regulated by the seasonal winds. An expected lag correlation between the velocity from mooring measurements and alongshore wind stress is detected near the frontal region. These results indicate that seasonal wind forcing plays an important role in the frontal activities and coastal water transport over the shelf.
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影响因子：
3.5
作者：
Boccaletti, Giulio;Ferrari, Raffaele;Fox-Kemper, Baylor
通讯作者：
Fox-Kemper, Baylor
影响因子：
5.2
作者：
Gula, J.;Molemaker, M. J.;McWilliams, J. C.
通讯作者：
McWilliams, J. C.
影响因子：
3.5
作者：
W. Zhang;G. Gawarkiewicz
通讯作者：
W. Zhang;G. Gawarkiewicz
影响因子：
64.8
作者：
PAULY, D;CHRISTENSEN, V
通讯作者：
CHRISTENSEN, V
DOI：
10.1073/pnas.0700462104
发表时间：
2007-03-06
影响因子：
11.1
作者：
Barth, John A.;Menge, Bruce A.;Washburn, Libe
通讯作者：
Washburn, Libe