电离层天气变化特性及对太阳风的响应，是电离层物理尚未解决的重要科学问题。电离层模式在现阶段面临极大的挑战，难以完美重现不同类型的空间天气事件期间的电离层扰动行为。本项目拟围绕低纬电离层天气变化，通过分析起源于日冕物质抛射及冕洞高速流的两类空间天气事件期间的低纬电离层演变，探究电离层扰动电动力学过程，揭示低纬电离层天气变化的全球性特性与区域特征，研究行星际太阳风参数如何驱动电离层天气过程和调制电离层气候学变化。通过发展观测数据约束的实用电离层同化技术，实现对典型空间天气事件下电离层演变的定量化模拟。以电场为线索突出耦合，有望在低纬电离层天气行为的全球特征与区域差异特性、电离层气候学特性与太阳风参数的关联等方面取得创新，以新的思路认识电离层特性与机理。本项目属于申请指南的"日地空间环境和空间天气"领域中"太阳风、磁层、电离层、中高层大气多时空尺度的结构、演化和耦合过程"重点资助方向。

The response of the ionosphere to varying solar wind conditions is an important and unresolved issue in ionospheric physics and provides an inevitable challenge for ionospheric modelings, at least at the current stage, the models have difficulties in reproducing the behaviors of the ionosphere under disturbance events. Under the support of this project, we aim to explore the response of the ionosphere at low latitudes to changes in solar winds under space weather events which are driven by coronal mass ejections and high-speed solar wind coronal streams, to investigate the electrodynamical processes in the disturbed ionosphere, to reveal the global and regional features in the changes in the ionosphere, and to study the correlations of the solar wind parameters with changes in ionospheric weather and climatology. Furthermore, we will develop an efficient ionospheric data assimilation technology, through including observationed information, to improve the model's ability to simulate the evolutions of the low latitude ionosphere under space weather events. The study will make novel progresses in understanding the global and regional features in changes in the ionosphere and the solar wind coupling with the ionosphere in ionospheric weather and climatology. The project belongs to the direction "The multiply structures, evolutions and couplings of the solar wind-magnetosphere-ionosphere-upper atmosphere system" in the high priority supporting fields "solar terrestrial environment and space weather".