Bullet Train of Giant Nonlinear Internal Waves from Luzon Strait

  • Liu, Cho-Teng (Institute of Oceanography, National Taiwan University) ;
  • Hsu, Ming-Kuang (Northern Taiwan Institute of Science and Technology) ;
  • Chen, Hsien-Wen (Department of Water Police, Central Police University) ;
  • Wang, Dee-Way (Institute of Oceanography, National Taiwan University) ;
  • Chyou, Yuan-Jie (Institute of Oceanography, National Taiwan University) ;
  • Lee, Chang-Wei (Institute of Oceanography, National Taiwan University)
  • Published : 2006.11.02

Abstract

In the northeastern South China Sea (SCS), fast westward moving (about 2.9 m/s) non-linear internal waves (NLIWs) are emanated nearly daily from the Luzon Strait. Their propagation speed is faster than NLIWs previously observed in the deep water of world oceans, their amplitude of 140 m or more is the largest free propagating NLIWs so far observed in the deep ocean. These NLIWs energized the top 1500 m of the water column, heaving it up and down in 20 min. Their associated energy density and energy flux are the largest observed to date. During 2005 and 2006 experiment, they were found west of the HengChun Ridge (HCR) that links Luzon and Taiwan Islands. This coincides with founding in satellite images, no NLIW front was found east of HCR. But, the turbulent environment east of HCR may prohibit surface signature of NLIWs that were emanated from sills between Batan Islands. The relative contribution of the two ridges on NLIW in Luzon Strait is still under study.

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