超强台风“灿都”(2021年)对黑潮入侵吕宋海峡的影响

The Intensity of Kuroshio Intrusion through the Luzon Strait under the Influence of Super Typhoon Chanthu (2021)

关键词:  台风“灿都”  吕宋海峡  黑潮入侵  海洋再分析  中尺度涡

Key words:  Typhoon Chanthu  Luzon Strait  Kuroshio intrusion  ocean reanalyses  mesoscale eddy

摘要:

探究台风“灿都”经过吕宋海峡附近时的海洋变化过程及其对黑潮入侵吕宋海峡的影响。基于涡尺度海洋再分析资料和中国气象局台风最佳路径数据，研究台风“灿都”经过吕宋海峡附近时海洋热力和动力结构的变化，及吕宋海峡输运对台风的响应。台风“灿都”经过菲律宾东部海域的次表层暖涡维持其强度并发展至巅峰阶段，沿途造成海温降低、海表高度降低、混合层加深等。台风位于吕宋海峡中线附近时，其右侧的暖涡与其发生相互作用，暖涡整体结构被打破。台风到达台湾岛东侧时，遇到其东侧的冷涡并使其加强，强化的负反馈机制使台风强度迅速减弱。在吕宋海峡附近，台风增强了从南海的输出流，抑制了黑潮向南海的入侵流。海峡剖面热能输送的变化与水体输运的变化较一致，而热含量的变化主要受到台风引起的输运异常的间接影响。中尺度涡旋在台风“灿都”发展过程中发挥着重要的作用，台风与暖涡的作用可能打破暖涡结构，与冷涡相遇则会使其加强。台风改变吕宋海峡输运结构主要是抑制中部入侵流和促进南侧输出流，激发出的海峡剖面上的输运异常波动在深层领先于浅层。

Abstract:

To investigate the responses of oceanic processes and the Kuroshio intrusion through the Luzon Strait when the super Typhoon Chanthu passed by the Luzon Strait region, the changes of oceanic thermal and dynamic structures and the response of Luzon Strait transport to the typhoon when it passes by the Luzon Strait region were studied, using the CMEMS eddy-scale ocean reanalysis data and the CMA tropical cyclone best track data. The results are shown as follows. Typhoon Chanthu maintained its intensity through a subsurface warm eddy and strengthened to its peak, resulting in the decrease of sea temperature and sea surface height, and the deepening of the mixed layer along its path. When the typhoon arrived at the central line of the Luzon Strait, a warm eddy on its right is destructed after interacting with it for some time. When the typhoon reaches the east side of Taiwan Island, it strengthened a cold eddy and was weakened by the enhanced negative feedback. The typhoon enhanced the outflow from the South China Sea and weakened the Kuroshio intrusion into the South China Sea. The change of ocean heat transport was consistent with that of water volume transport, and the change of ocean heat content was mainly indirectly affected by typhoon-induced transport anomalies. The mesoscale eddy plays an important role in the development of the typhoon. The typhoon may break a warm eddy, or strengthen a cold eddy. The typhoon is considered to suppress the intrusion flow at the central strait and strengthen the outflow at the southern strait, and the stimulated fluctuations of anomalous transport through the Luzon Strait in the deep layer are shown to lead the anomalies in the shallow layer.