Based on the velocity data near the Kuroshio in the Luzon Strait from August 2010 to April 2011,the propagation characteristics of near-inertial internal waves(NIWs)induced by typhoons under the Kuroshio modulation are studied.The results show that during the passage of Typhoons Megi,there was strong NIWs generation in the upper layer,and the maximum near-inertial velocity reached 0.4 m·s-1.The maximum near-inertial kinetic energy on the east side of Kuroshio(Pacific Ocean)was 2～3 times stronger than that on the west side(South China Sea).This spatial difference is inconsistent with the wind energy input.During Typhoon Megi,the wind energy on the eastern side of Kuroshio was weaker than that on the western side.The results of velocity and shear power spectrum analysis show that the upper near-inertial spectrum peak on the east side of Kuroshio is significantly redshifted com-pared with that on the west side.The NIWs'propagation can be modulated by the corresponding cur-rents and vorticity field changes caused by the Kuroshio morphology.According to the results of ray tracing experiments,the advection effect of Kuroshio transported the NIWs far from the source.The positive vorticity on the west side of the current axis hindered the propagation of the NIWs.In contrast,the negative vorticity on the east side could make the NIWs gather.
关键词
吕宋海峡/近惯性内波/台风/黑潮/射线追踪
Key words
the Luzon Strait/near-inertial waves/typhoons/Kuroshio/ray tracing
维普
万方数据