Polar cap patches are known as islands of enhanced electron density in the polar cap F region ionosphere. To observe the airglow signature of polar cap patches continuously at a fixed point near the center of the MLAT/MLT coordinate system, we started operating an all-sky imager in Eureka, Canada since 2015, where the magnetic latitude is ~87°. By statistically analyzing the 630-nm airglow images from Eureka, it was identified that the luminosity of patches, which is proportional to the electron density in the F region, increases during specific UT interval from 16 to 22 UT. This outstanding UT variation of patch luminosity can be explained simply by the systematic shift of the terminator in the MLAT/MLT coordinate system due to the offset between the geographic and geomagnetic pole. That is, the spatial relationship between the dense source plasma in the sunlit area and the high-latitude convection system controls the UT variation. We also found that when the IMF By is positive, the number of polar cap patches was twice of that in the negative IMF By. By deriving average convection patterns from the archived SuperDARN map potential data, we confirmed that the configuration of plasma convection is more appropriate for patches to be transported toward the magnetic pole during the positive IMF By condition.

极帽贴片被称为极帽 F 区电离层中电子密度增强的岛。为了在 MLAT/MLT 坐标系中心附近的固定点连续观察极冠斑块的气辉特征，我们从 2015 年开始在加拿大尤里卡运行全天空成像仪，那里的磁纬度约为 87°。通过对 Eureka 的 630 nm 气辉图像进行统计分析，发现在特定 UT 间隔从 16 到 22 UT 期间，与 F 区域中的电子密度成正比的补丁的亮度增加。这种突出的 UT 斑块光度变化可以简单地解释为由于地理磁极和地磁极之间的偏移而导致 MLAT/MLT 坐标系中终止符的系统偏移。那是，日照区的致密源等离子体与高纬度对流系统之间的空间关系控制着 UT 的变化。我们还发现，当IMF By为正时，极冠斑块的数量是IMF By为负时的两倍。通过从存档的 SuperDARN 地图电位数据中推导出平均对流模式，我们确认等离子体对流的配置更适合在正 IMF By 条件下向磁极传输的补丁。