泰利台风对台湾东北黑潮入侵东海陆架影响的研究

THE INTENSITY OF KUROSHIO INTRUSION OFF NORTHEASTERN TAIWAN UNDER THE INFLUENCE OF SUPER TYPHOON TALIM

本文利用卫星高度计数据和分析数据,并结合同时期现场深水潜标的流速观测数据,研究了超强台风泰利过境前后台湾东北附近海域流场、位势密度场、位势涡度场以及黑潮入侵东海陆架强度的变化。分析结果表明,泰利台风通过改变台湾东北陆坡附近海域的流场、位势密度场,显著地削弱(增强)了西段(东段)陆坡附近的位势涡度梯度,从而使得西段(东段)陆坡黑潮入侵东海陆架的强度显著增强(减弱)。此外,本文还区分了台湾东北西部陆坡附近表层的跨陆坡“上凸型”位势涡度分布与次表层的跨陆坡“下凹型”位势涡度分布,并认为次表层的跨陆坡“下凹型”位势涡度分布也应作为台湾东北西部陆坡附近“位势涡度障碍”的重要组成部分。本文的研究结果揭示了大气中的台风过程对台湾东北黑潮入侵东海陆架产生显著影响的关键过程及机制,相关结论可为台湾东北黑潮入侵东海陆架变化规律的研究提供有价值的参考。

Based on satellite altimeter and analysis data,in conjunction with mooring observations,we studied the variations of the flow field,potential density field,potential vorticity(PV)field and Kuroshio intrusion intensity off the northeastern Taiwan under the influence of super typhoon Talim.The results suggest that super typhoon Talim significantly weakened(enhanced)the potential vorticity gradient across the western(eastern)slope off northeastern Taiwan by changing the flow field and potential density field,thus,resulting in the enhancement(weakening)of the Kuroshio intrusion through the western(eastern)slope.In addition,this study distinguished the“downward concave”crossshelf PV distribution in the subsurface layer from the“upward convex”crossshelf PV distribution in the surface layer near the western slope.At last,we proposed the mechanisms of typhoons in the atmosphere affecting the Kuroshio intrusion off the northeastern Taiwan.