|  |
Program |
 |
| |
 |
Special Session 6: The ocean’s energy cascade and mixing |
| |
|
|
Study of internal waves and internal solitary waves shoaling by observations and numerical simulations
Wednesday 11th @ 1400-1420
Multi-function Hall
Haibin Song* , State Key laboratory of Marine Geology, School of Ocean and Earth Science, Tongji University
Yongxian Guan, Key Laboratory of Marine Mineral Resources, Ministry of Land and Resources, Guangzhou Marine Geological Survey
Shengxiong Yang, Key Laboratory of Marine Mineral Resources, Ministry of Land and Resources, Guangzhou Marine Geological Survey
Yang Bai, State Key laboratory of Marine Geology, School of Ocean and Earth Science, Tongji University
Xitong Huang, State Key laboratory of Marine Geology, School of Ocean and Earth Science, Tongji University
Presenter Email: hbsong@tongji.edu.cn
|
| Internal waves and internal solitary waves(ISWs) are ubiquitously distributed in marginal seas and coastal oceans. When they propagate from deep ocean basin to continental slope and shelf, internal waves and ISWs are shoaling. Breaking and dissipation of internal waves in continental shelf and slope make major contribution to ocean mixing, stratification change and enhancement of productivity and sediment transport. Shoaling internal waves and ISWs are very important for sediment resuspension, sediment transport, shelf and slope crossing particle and nutriment transport, seafloor geomorphology shaping, etc. ISWs are strong energy and nonlinear internal waves, which cause strong bottom current and bottom boundary layer instability under them, as an important dissipation mechanism and one dynamic drive for sediment resuspension. In the internal water column, shear instability caused by ISWs provide a mechanism for wave field dissipation and vertical mixing of heat and nutriment. Shoaling internal waves form boluses, driving sediment and high density fluid to flow upslope. ISW breaking can be classified to different types, such as collapsing breaking, plunging breaking, etc, which cause the mixing of the whole water-column. ISW breaking drive flow separation and eddy shedding off at the back of depression ISW. Most studies show that the ISW breaking make great contribution to primary production enhancement at particular locations. Field observations show the internal wave field in continental shelf and slope is very complex. Theoretical study, numerical simulation and lab experiment usually pay attention to simple geometric assumption. It is necessary to carry out numerical simulations with real stratification and complex geometric condition for better understanding the deep water processes in real ocean.
We studied the ISW shoaling process in the Dongsha region of South China Sea with multi-beam bathometry data, multi-channel seismic data, remote sensing images and numerical simulation results, and we focused on the relationship between internal wave shoaling and local topography. We discussed the following scientific problems: (1)slope and critical slope;(2)waveform change during internal waves' and ISWs' shoaling; (3)instability during shoaling process; (4)shoaling process and sediment resuspension; (5) shoaling process and particle transport; (6)bottom boundary layer during shoaling process; (7)shoaling process and upper slope dunes.
|
|
|
|
|