该项目将综合利用电离层和热层卫星探测结合地面观测数据以及数值模拟技术，研究中纬热层纬向风的经度变化及其产生机制，具体包括：研究不同太阳活动水平、季节和地方时扇区热层纬向风的经度分布；揭示地磁偶极倾斜（dipole tilt）对纬向风经度分布的影响；讨论不同太阳和地磁活动水平情况下中纬过程（太阳辐射加热、离子拖曳）和高纬过程（焦耳和离子沉降加热、Coriolis力）对纬向风经度分布的相对影响；探讨亚极光区极化流（Subauroral Polarization Streams，SAPS）和对流层大气潮汐波对热层纬向风经度分布的影响。该研究对于深入理解电离层-热层耦合系统、提高空间天气建模和预测能力有重要意义。

The project aims at disclosing physical mechanisms of longitudinal variation of thermospheric zonal wind at mid-latitudes. Satellite observations and ground based measurements in combination with model simulations are used for investigation. Details include: (1) study the longitudinal variation of zonal wind (∆U) for different seasons and under different solar and magnetic activity conditions; (2) disclose the geomagnetic dipole tilt effect on ∆U; (3) discuss the relative importance of effects on ∆U from solar radiation, ion drag, and high latitude activity (Joule heating and particle precipitation heating, Coriolis force); (4) analyze SAPS (Subauroral Polarization Streams) effects and tidal effect from troposphere on ∆U. The study is essential for better understand ion-neutral interactions and to improve space weather modeling and forecasting abilities.