講者：郭怡君 博士 (臺灣大學海洋研究所)
題目：Enhanced Internal Tide Generation by Typhoon Nepartak in the Luzon Strait and Kuroshio Region.
時間：9月25日(四) 14:20-15:20
地點：海研所2樓大講堂
演講摘要:
Mooring observations from July 5 to 11, 2016, showed a remarkable amplification of internal solitary waves along the continental shelf of the northern South China Sea. This amplification originated from the internal tides generated in the Luzon Strait (LS), influenced by the passage of Category 5 Super Typhoon Nepartak through southern Taiwan. Through a series of model sensitivity experiments, we identified that the typhoon-induced Kuroshio change plays a crucial role in this process. As the typhoon approached, both the stratification and subsurface velocity of the Kuroshio intrusion in the LS intensified, leading to a 10% increase in depth-integrated baroclinic tidal energy conversion of M2. In particular, the semidiurnal (M2) internal tide generation was amplified. This enhancement occurred only before the typhoon reached east coast of Taiwan. The intensified internal tides likely contributed to the observed amplification of internal solitary waves on the continental shelf. Additionally, we address the underlying mechanisms driving the enhanced stratification and current shear in the Kuroshio, attributing them to the interaction of the ocean front with Ekman flows and other transient oceanic responses triggered by the approaching typhoon.
