Upper pycnocline turbulence in the northern South China Sea

The first regional mapping of the averaged turbulent kinetic energy dissipation rate 〈ɛ p 〉 in the upper pycnocline of the northern South China Sea is presented and discussed. At φ = 20°N and to the north of this latitude, 〈 ɛ p 〉 appears to be more than two times larger than that to the south of 20°N. It is suggested that this asymmetry is associated with the predominant northwestward propagation and dissipation of the internal waves originated in the Luzon Strait area. An approximately linear relationship between 〈ɛ p 〉 and the available potential energy of the waves P IW, suggests a characteristic time of the P IW dissipation of about 6 h.