In situ observation of contour currents in the northern South China Sea: Applications for deepwater sediment transport
In situ observation of contour currents in the northern South China Sea: Applications for deepwater sediment transport
复制标题
南海北部等高线流的现场观测：在深水沉积物输送中的应用
DOI：
10.1016/j.epsl.2015.09.008
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发表时间：
2015-11
影响因子：
5.3
通讯作者：
Xu, Jingping
中科院分区：
文献类型：
--
作者：
Li, Jianru;Wang, Meng;Wang, Wenguang;Xu, Jingping
2011年9月至2013年5月，利用声学多普勒海流剖面仪锚泊系统获取了南海北部中国海域的深水水流和相关悬沙浓度，以表征等高线水流的分布特征，并评价其输沙能力。流速大小一般在0~2 cm/S范围内变化，优势流向为∼2 5 0°(西南向)。观测到的等高线水流定义为深水水流的沿坡分量，具有隧道状的垂直结构，最大流速出现在隧道中间，向外递减。最大流速的大小和深度范围都表现出明显的季节变化，夏季流速最强，春季最弱，等值线水流厚度冬季最大，春季最小。我们还发现，深部中尺度涡旋的通过对等高线电流的大小和方向有显著的影响。由回波强度估算的悬浮泥沙浓度在近底最高(>；400μg/L)，在水深小于1750m时逐渐减小到<；10μg/L，高悬沙浓度主要出现在等深流强度较低的时段，说明海底泥沙再悬浮不是高悬沙事件的主要控制因素。我们的观测还表明，等深流的主要作用是通过使沉积物悬浮在南中国海下陆坡上方来输送来源地的沉积物。
Deepwater currents and related suspended sediment concentration were obtained by an Acoustic Doppler Current Profiler (ADCP) mooring system in the northern South China Sea from September 2011 to May 2013 to characterize the occurrence of contour currents and to evaluate their sediment transport capacity. Magnitude of the current velocity generally varied in the range of 0–2 cm/s, with a dominant flow direction of ∼250° (southwestward). The observed contour current, defined as the along-slope component of the deepwater currents, has a tunnel-like vertical structure with the largest velocity occurring in the middle of the “tunnel” and decreasing outwards. Both the magnitude and the depth range of the maximum velocity display evident inter-seasonal variations, with the strongest velocity in summer and the weakest in spring, while the thickness of the contour currents was the highest in winter and the lowest in spring. We also found that passing-through of the deep-reaching mesoscale eddies significantly affected the magnitude and direction of the contour currents. The suspended sediment concentration (SSC) estimated from echo intensities of the ADCP is the highest at the near-bottom (>400 μg/L) and decreases upwards to <10 μg/L at water depth shallower than 1750 m. High SSC is mostly observed during periods of low magnitude of the contour currents, suggesting resuspension of sediment from the seafloor is not the major controlling factor of these high-SSC events. Our observation also suggests that the major role that contour currents play is to transport sediment from the sources through keeping sediment suspended above the lower continental slope of the South China Sea.
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影响因子：
2.3
作者：
P. Traykovski;P. Wiberg;W. Geyer
通讯作者：
P. Traykovski;P. Wiberg;W. Geyer
影响因子：
2.9
作者：
L. Quaresma;J. Vitorino;Anabela Oliveira;José da Silva
通讯作者：
L. Quaresma;J. Vitorino;Anabela Oliveira;José da Silva
DOI：
10.1002/2013jd020763
发表时间：
2013-12
期刊：
Journal of Geophysical Research: Atmospheres
影响因子：
--
作者：
Ying Li;G. Kirchengast;B. Scherllin-Pirscher;Suqin Wu;M. Schwaerz;J. Fritzer;S. Zhang;B. Carter-B.-Car
通讯作者：
Ying Li;G. Kirchengast;B. Scherllin-Pirscher;Suqin Wu;M. Schwaerz;J. Fritzer;S. Zhang;B. Carter-B.-Car
影响因子：
2.2
作者：
L. Gostiaux;H. Haren
通讯作者：
L. Gostiaux;H. Haren
DOI：
10.1007/bf02907084
发表时间：
2001-10
期刊：
Science in China Series D: Earth Sciences
影响因子：
--
作者：
L. Shao;Xian‐Hua Li;G. Wei;Yuanfang Liu;D. Fang
通讯作者：
L. Shao;Xian‐Hua Li;G. Wei;Yuanfang Liu;D. Fang