This study is the first to depict typhoon-induced continental shelf wave (CSW) propagation in the eastern Taiwan Strait (TWS) during the passage of Typhoon Meranti in 2016 using tidal gauge data and along-track satellite altimeter data. The strong amplitude response of sea level oscillations (within the range of 0.30-0.54 m) as a free, barotropic CSW after Meranti, which impacted the TWS, was clearly detected in time and frequency (in bands of 64-81 h) using wavelet and cross-wavelet analyses. The measured group and phase speeds were consistent with the dispersion curves for CSW with the first-mode derived from the cross-shelf sections of the eastern TWS, with the mean speeds reaching 3 and 5.6±0.7 m/s, respectively.Coincidentally, the typhoon-induced sea level anomaly (SLA) was also captured by the satellite altimeter before this CSW entered into the TWS. Using the theoretical cross-shore CSW modes to fit the SLA data, the results indicated that the first three wave modes can interpret this CSW event appeared in the southern TWS very well, with the first mode being the dominant one.

2016年莫兰蒂台风期间台湾海峡东部大陆架波传播观测

中文摘要：该研究首次利用验潮资料和卫星高度计沿线资料，描述了2016年台风莫兰蒂过境期间，台风诱发的大陆架波(CSW)在台湾海峡(TWS)东部的传播情况。在时间和频率上(64 ~ 81 h频带)都能清晰地检测到莫兰蒂过境后一个自由的正压海流对海平面振荡(0.30- 0.54 m范围内)的强烈振幅响应。测得的群速度和相速度与由东部横向陆架剖面得到的第一模CSW的色散曲线相一致，平均速度分别为3和5.6±0.7m/s。巧合的是，台风引起的海平面异常(SLA)也是在CSW进入TWS之前被卫星高度计捕捉到的。结果表明，前三个波模可以很好地解释出现在南太平洋海面上的CSW事件，其中第一个波模占主导地位。