西太平洋内潮与环流的多尺度相互作用及动力机制

本项目重点针对西太平洋地球系统多圈层重大计划2020年资助方向“西太平洋复杂地形下海洋多尺度相互作用与能量串级”，聚焦西太平洋内潮与环流多尺度相互作用动力学开展前沿研究。因复杂地形的存在，西太平洋是全球最强内潮发生区域，具有复杂多时空尺度环流系统（如大尺度赤道流系、黑潮、中尺度涡旋）。目前，对西太平洋内潮与多尺度环流相互作用及能量交换过程尚不清楚，从而制约了对该海域多尺度相互作用及能量串级的系统认知。.围绕“西太平洋内潮与环流多尺度相互作用的关键驱动机制”这一核心科学问题，本项目拟采用数据分析、数值模拟和理论建模手段，揭示环流背景场与内潮生成能量分布的关联，评估多动力因子对内潮传递路径变异的相对贡献，阐明内潮-多尺度环流相互作用及双向能量交换机制，探明潮致混合对环流变异反馈作用，以此提炼中-小尺度内潮和慢变性环流在西太平洋多尺度能量系统中作用的动力认知，补充完善西太平洋多尺度动力理论框架。

This project focuses on the key funding issue “Interactions and Energy Cascade of Multi-scale Dynamical Processes under the complex topography in the western Pacific Ocean”, and will carry out frontier research on the interaction of internal tide and multi-scale circulation system in the western Pacific. The western Pacific features the strongest internal tides in the World Ocean due to its complex bottom topography. The western Pacific possesses globally typical multi-scale circulation system (such as the basin-scale equatorial currents, Kuroshio and mesoscale eddy). At present, the interaction and energy exchange process between internal tide and multi-scale circulation in the western Pacific is largely unknown, which restricts the systematic cognition of the interaction and energy cascade of multi-scale processes in the western Pacific..This project centers on the key scientific question “The key driving mechanism of the interaction between internal tides and multi-scale circulation in the Western Pacific”. Based on high-resolution data analysis, refined numerical simulation and theoretical methods, this project aims to reveal the relationship between the background circulation field and the energy distribution of internal tide generation, evaluate the influence and relative contributions of multiple factors to the variation of internal tide long-distance radiation, elaborate the dynamical mechanism of the multi-scale circulations on the evolution of internal tide, analyze the bidirectional energy exchange accompanied by the wave-current interaction, and clarify the feedback effect of tide-induced mixing on the variation of the multi-scale circulation. The anticipated results can help extract the dynamical cognition of meso-small-scale internal tide and slowly varying circulation system in the multi-scale energy cascade system, which will make an important supplement to the dynamic framework of multi-scale processes in the western Pacific.