基于卫星高度计的北太平洋热带水年际变异研究

The North Pacific tropical water (NPTW) is formed in the center Pacific and advected by subtropical gyre to the tropical region, propagating the mid-latitude air-sea signal anomaly to the tropical Pacific. It plays an important role in modulating the global salinity flux balance and climate system. Due to the observation paucity, there are still many problems unsolved in the structure and variation of NPTW. Focus on ‘the interanual variation of NPTW in the NEC advection region’, the applicant will utilize satellite altimetric measurement and Argo data, combined with a stream-function projection method, to diagnose the NEC hydrography. We will distinguish NPTW structure, analysis its interannual variation, and finally examine the key physical process of NPTW variation based on dynamic diagnoses method and discuss the relation between interannual variation of NPTW and ENSO/PDO.

北太平洋热带水（NPTW）自源地生成后经由副热带流系输运到达热带海区，并将中高纬度的海气信号异常传播到热带太平洋，对全球盐量平衡以及气候系统具有重要的调控作用。受观测资料所限，NPTW的结构及其变异特征仍存在诸多需要解决的问题。围绕“NPTW随北赤道流输运过程中的年际变异特征”这一科学问题，本项目拟综合利用卫星高度计数据和Argo资料，并结合一种流函数空间投影方法对北赤道流海域进行水文诊断分析，辨识并分析NPTW的结构和年际变异特征，最终通过动力学诊断方法研究导致水团变异的主要物理过程，并探讨NPTW年际变异与PDO和ENSO的关系。