This study examines the influence of space weather conditions on ionospheric TEC variations at different latitudes around the world. According to the space weather condition indices (geomagnetic storm-activity indices, solar activity indices, magnetic field change indices, plasma density and proton flux indices) different time periods were chosen. GPS observations were used to obtain TEC data derived from International GNSS Service (IGS) stations located at northern and southern hemisphere latitude regions (equatorial, mid-latitude and high latitude). GPS TEC data were evaluated associated with the space weather conditions using 15-day running median statistical analysis method. The results showed that besides the commonly used geomagnetic storm-activity and solar activity indices, plasma density, magnetic field change and particle flux indices are also important in determining whether there is any TEC anomaly in the ionosphere. This study illustrated that all indices should be examined in the applications associated with the ionosphere and particularly in the research of pre-earthquake ionospheric anomalies.

中文翻译：

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空间天气条件引起的电离层TEC异常调查

本研究考察了空间天气条件对世界各地不同纬度的电离层 TEC 变化的影响。根据空间天气条件指数（地磁暴活动指数、太阳活动指数、磁场变化指数、等离子体密度和质子通量指数）选择不同的时间段。GPS 观测用于获取来自位于北半球和南半球纬度区域（赤道、中纬度和高纬度）的国际 GNSS 服务 (IGS) 站的 TEC 数据。使用 15 天运行中值统计分析方法评估与空间天气条件相关的 GPS TEC 数据。结果表明，除了常用的地磁暴活动指数和太阳活动指数外，等离子体密度、磁场变化和粒子通量指数对于确定电离层中是否存在任何 TEC 异常也很重要。该研究表明，在与电离层相关的应用中，特别是在震前电离层异常研究中，应检查所有指标。