? Quick Search: ? ? ? Advanced Search
LIU Qian,XIE Xiaohui,SHANG Xiaodong,CHEN Guiying,WANG Hong. 2019. Modal structure and propagation of internal tides in the northeastern South China Sea. Acta Oceanologica Sinica, 38(9):12-23
Modal structure and propagation of internal tides in the northeastern South China Sea
南海东北部内潮的模态结构和传播
Received:August 21, 2018??
DOI:10.1007/s13131-019-1473-1
Key words:South China Sea??internal tides??propagation??scattering??modal structure
中文关键词:??南海??内潮??传播??散射??模态结构
基金项目:The State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences under contract No. LTO1915; the National Natural Science Foundation of China under contract Nos 41630970, 41876016, 41676022 and 41521005; the Instrument Developing Project of the CAS under contract No. YZ201432.
Author NameAffiliationE-mail
LIU Qian?School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China
State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China?
?
XIE Xiaohui?State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China??
SHANG Xiaodong?State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China?xdshang@scsio.ac.cn?
CHEN Guiying?State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China??
WANG Hong?School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China??
Hits:?30
Download times:?41
Abstract:
??????The evolution of energy, energy flux and modal structure of the internal tides (ITs) in the northeastern South China Sea is examined using the measurements at two moorings along a cross-slope section from the deep continental slope to the shallow continental shelf. The energy of both diurnal and semidiurnal ITs clearly shows a~14-day spring-neap cycle, but their phases lag that of barotropic tides, indicating that ITs are not generated on the continental slope. Observations of internal tidal energy flux suggest that they may be generated at the Luzon Strait and propagate west-northwest to the continental slope in the northwestern SCS. Because the continental slope is critical-supercritical with respect to diurnal ITs, about 4.6 kJ/m2 of the incident energy and 8.7 kW/m of energy flux of diurnal ITs are reduced from the continental slope to the continental shelf. In contrast, the semidiurnal internal tides enter the shelf because of the sub-critical topography with respect to semidiurnal ITs. From the continental slope to the shelf, the vertical structure of diurnal ITs shows significant variation, with dominant Mode 1 on the deep slope and dominant higher modes on the shelf. On the contrary, the vertical structure of the semidiurnal ITs is stable, with dominant Mode 1.
中文摘要:
??????通过在南海东北部深的陆坡区和浅的陆架区获得的两套潜标观测资料,我们研究了南海东北部内潮的能量、能量通量和模态结构的演变。全日内潮的能量和半日内潮的能量都显示了明显的14天大小潮周期的变化,但是全日内潮和半日内潮和对应的正压潮之间具有一定的相位延迟,这表明观测区的内潮并不是在陆坡区产生的。通过观测数据,我们计算了内潮的能通量,内潮能通量的计算结果表明观测区的内潮有可能产生于吕宋海峡,内潮在吕宋海峡产生之后向西-西北方向传播并传播到了南海西北部的陆坡区。由于观测海区的陆坡对于全日内潮是临界-超临界地形,全日内潮从陆坡区传播到陆架区过程中,大约有4.6 KJm-2的全日内潮能量和8.7KWm-1全日内潮能通量减少。相反,由于观测海区的地形对于半日内潮是次临界地形,大部分半日内潮传播到了陆架区。内潮从陆坡区传播到陆架区过程中,全日内潮的垂直结构发生了很大的变化,全日内潮在陆坡区以模态一全日内潮为主,传播到陆架区后,全日内潮以高模态为主。相反,半日内潮的垂直结构比较稳定,以模态一结构为主。
HTML View Full Text ??View/Add Comment??Download reader
Close