南海上层对台风响应的模拟研究

Upper Ocean Response of the South China Sea to Typhoon Chanchu(2006)

利用中尺度海气耦合模式对2006年第1号台风Chanchu海气相互作用的模拟结果,分析了南海上层海洋对台风的热力和动力响应特征。研究发现:模拟的Chanchu影响下南海SST分布与观测较为符合;与SST降低相对应的是混合层深度普遍增加,较大的海面冷却对应了较大的混合层加深;在台风作用下,海面上产生了一个气旋式环流,随着台风中心的移动而移动,流场呈现明显的不对称结构;模拟结果表明南海对台风的响应具有很明显的近惯性振荡特征。

In order to investigate the dynamic and thermal response of the South China Sea （SCS） to real typhoon case qualitatively, the simulated results from a typhoon-ocean coupled model are analyzed in detail. The SST simulated by POM in the coupled experiment is in good agreement to that from the TRMM/TMI-derived data. Corresponding to the SST cooling, the depth of mixed layer deepens in the meantime, it deepens more distinctly on the right side of typhoon, with maxima of 58 m. The correspondence of SST cooling and mixed layer depth indicates that the SST cooling is caused mainly by entrainment. Under the influence of typhoon, a cyclonic circulation is generated in the upper ocean layer and moves with typhoon. The typhoon-induced horizontal currents in the wake of the storm have strong near-inertial oscillation, which gradually propagates downward.