Numerical Study Of The Response Of The South China Sea To Typhoon Imbudo

Typhoon is a strong atmosphere system happened above the ocean, which is the most intuitionistic expression of air-sea interaction. The cyclonic stress on the sea surface and the strong mixing processes forced by the typhoon play an important role in the processes of the heat, energy and mass exchange between the upper ocean and the deep ocean. Therefore, the study of the ocean response to the typhoon is an important scientific issue.Firstly, the wave field of the South China Sea (SCS) during the process of Typhoon Imbudo is calculated by the WWATCH-Ⅲmodel. The results indicate that the max field of significant wave height (SWH) travels west as the typhoon moves to the westward. The SWH and wave age is larger at the typhoon center. And far away from the typhoon center, the SWH becomes smaller and the wave becomes younger. At the same time, the SWH is larger by the right side of the typhoon track. Furthermore, the wind stress at the sea surface is calculated considering the wave introduced stress as a base of circulation model.Then, the response of the SCS to Typhoon Imbudo is examined using POM model, which is driven by the wind stress calculated above by the wave model. The results indicate that SST decreases by2～6°C with a rightward-biased response as Typhoon Imbudo passes across the SCS. Due to a strong mixing process, the mixed layer (ML) depth deepens as much as 10～60m and ML heat budget loses 824.78W /m~2, which is dominated by the vertical mixing. By the response of upper ML heat transport, the temperature below the ML increases and oscillates near the inertial period. Furthermore, strong inertial currents are generated by the storm with the max currents up to 1.4 m/s in the upper ML.Finally, the conclusions are drawn and several prospects of future study are formulated.