利用COSMIC掩星资料研究电离层赤道不规则体统计特性

夜间赤道电离层中的电离层不规则体及闪烁，是当代先进的星地信息系统面临的主要空间天气灾害之一。传统地基GNSS和光学成像设备是电离层闪烁和不规则体重要观测手段，能有效给出其水平结构和变化信息，但缺乏垂直分辨能力。这不仅不利于更深入研究不规则体物理机理，也降低了利用地基观测信息进行电离层闪烁预警预测精度。掩星观测可有效提取电离层闪烁及不规则体信息，不仅具有全球观测能力、更有较好的垂直分辨能力。本项目使用2006年以来最为完整的COSMIC掩星资料，发展准确的不规则体信息提取方法，统计研究不规则体的全球分布规律，并针对电离层不规则体随太阳、地磁活动变化的复杂表现，重点考察不同高度上不规则体对太阳活动响应的差异，研究不同磁暴类型对不规则体影响的差异，尝试探讨电场垂直漂移等参量通过瑞利-泰勒不稳定增长机制对不规则体的影响。最后，建立不规则体垂直信息经验模型，用于地面光学成像反演和电离层闪烁的预测预警

The ionospheric irregularities and scintillation in the equatorial ionosphere at night are one of the major space weather disasters for satellite-ground information systems. The traditional ground-based GNSS and optical imaging equipment are the means of observing the ionospheric scintillation and irregular, which can effectively give information about their horizontal structure and variation, but lack of vertical information. It would hamper the physical mechanism of irregularities and application. Radio Occultation (RO) can effectively retrieve ionospheric scintillation and irregularities information, which not only has global observing ability but also vertical resolution. We will use the most complete COSMIC data since 2006 to develop accurate methods for retrieving irregularities and statistically study the global distribution. In view of the complicated behavior of the irregularities under different solar and geomagnetic activity, the response of the irregularities to the solar and geomagnetic activity is mainly investigated. We also discuss the effect of the ionospheric vertical drift and other parameters on the irregularities through the Raleigh-Taylor instability growth mechanism. Finally, an empirical model of irregularities including vertical information is established for the optical imaging inversion and ionospheric scintillation prediction.