【摘要】 本文采用电离层测高仪数据对北京上空中小尺度电离层扰动进行了事例分析和统计研究.利用PDI电离层测高仪的快速扰动探测数据，分析了2017年11月13日北京上空典型的中小尺度电离层扰动事件.结果表明，电离层测高仪直接观测的电离层频高图上的V形(或U形)下降结构，是中等尺度电离层扰动的一种“显式”特征.小尺度电离层扰动主要出现于较低的高度，并不伴随着电离层频高图上显著的异常结构.通过统计2010—2021年电离层频高图数据中的电离层异常描迹事件，分析了北京上空中等尺度电离层扰动的发生率特征.以这些特殊描迹为特征的电离层扰动主要是白天现象，且冬季的发生率显著高于其他季节.其发生率与太阳活动呈反相关，即太阳活动较强时中等尺度电离层扰动的发生率较低，与地磁活动的相关性尚不十分明确.更多还原

【Abstract】 In this paper, characteristics of medium and small-scale ionospheric disturbances over Beijing were studied by ionosonde observation data. The cases of medium and small-scale ionospheric disturbances over Beijing on Nov.13, 2017 were analyzed using the rapid-run observation data of the PDI ionosonde. The results show that the V-shaped(or U-shaped) descending structure in the ionograms is an “explicit” feature of the medium-scale ionospheric disturbance. On the other hand, the small-scale ionospheric disturbances mainly occur at lower altitudes. They are not accompanied by distinct anomalous structures in the ionograms. The characteristics of the occurrence rate of medium-scale ionospheric disturbances over Beijing were presented by statistically studying the abnormal trace events in ionograms from 2010 to 2021. The median-scale ionospheric disturbance characterized by these abnormal traces is a mainly daytime phenomenon. Its occurrence rate is significantly higher in winter than those in other seasons. Furthermore, the occurrence rate is higher under low solar activities, which shows an inverse correlation with solar activity. The correlation with geomagnetic activity is still unclear.更多还原