Observing spectral characteristics over a continental shelf and slope in the South China Sea

Using in situ measurement data from May-June,1998,and data from the Asian seas international acoustics experiment（ASIAEX） from 2001 in the South China Sea（SCS）,the spectral density function and the dissipation spectrum function are estimated.In the infra-gravity wave（IGW） band,the power spectra of velocity [u,v,w) are universal functions with respect to characteristic frequencies,which correspond to the peak frequencies of the dissipation spectrum（PFDS）.This suggests that high-frequency internal waves in the IGW band have similar dynamical characteristics.In addition,the evolution of these characteristic frequencies is explored and its highest value is 8.8 cph(cycles per hour,1 cph=2.778×10-3 Hz).