Coupling Between E Region Quasi-Periodic Echoes and F Region Medium-Scale Traveling Ionospheric Disturbances at Low Latitudes
Coupling Between E Region Quasi-Periodic Echoes and F Region Medium-Scale Traveling Ionospheric Disturbances at Low Latitudes
复制标题
低纬度E区准周期回波与F区中尺度行进电离层扰动的耦合
DOI：
10.1029/2019ja027720
复制
发表时间：
2020
影响因子：
2.8
通讯作者：
Ning Baiqi
中科院分区：
文献类型：
--
作者：
Xie Haiyong;Li Guozhu;Zhao Xiukuan;Ding Feng;Yan Chunxiao;Yang Guotao;Ning Baiqi
在低纬度地区同时观测到来自 VHF 相干反向散射雷达的 E 区准周期（QP）回波、来自数字探测器的零星 E（Es）层以及来自全球导航卫星系统接收器的 F 区中尺度行进电离层扰动（MSTID）。 2018年3月3日晚的结果显示，雷达高度-时间强度图中的QP回波聚集成组，与MSTID和strongEslayer的周期一致。 MSTID的相锋沿西北-东南方向拉长，并从中纬向西南传播。与MSTID的传播方向类似，低纬度Eslayers也向西南方向传播。对于 QP 回波星团，从雷达多波束观测中可以看到向西漂移。 QP 回波的多普勒速度显示出波束依赖性，最西端波束中的正值（远离雷达的运动）显着增强。根据2018年3月至6月期间的初步统计分析发现，在总共102个夜晚中，有32个夜晚产生了QP回波。在六个晚上观察到 QP 回波和 MSTID 同时出现。我们认为，当来自中纬度的 MSTID 接近低纬度时，与 MSTID 相关的极化电场可以通过 E-F 区电动力耦合调制 E 区等离子体不稳定性，在低纬度产生 QP 回波。
Eregion quasi‐periodic (QP) echoes from a VHF coherent backscatter radar, sporadicE(Es) layer from a digisonde, andFregion medium‐scale traveling ionospheric disturbances (MSTIDs) from global navigation satellite systems receivers were simultaneously observed at low latitudes. The results on the night of 3 March 2018 show that the QP echoes in radar height‐time intensity maps were clustered into groups, coinciding with the periods of MSTIDs and strongEslayer. The MSTIDs had phase fronts elongating in the northwest‐southeast direction and propagated southwestward from middle to low latitudes. Similar to the propagation direction of MSTIDs, the low‐latitudeEslayers also propagated southwestward. For the QP echoing clusters, a westward drift was seen from the radar multibeam observations. The Doppler velocities of QP echoes show beam dependence, with significantly enhanced positive values (motion away from the radar) in the westernmost beam. Based on a preliminary statistical analysis during the period March–June 2018, it was found that out of a total of 102 nights, there are 32 nights when QP echoes were generated. The simultaneous occurrences of QP echoes and MSTIDs were observed on six nights. We suggest that when the MSTIDs coming from middle latitudes approach low latitudes, the polarization electric fields associated with the MSTIDs could modulate theEregion plasma instability producing QP echoes at low latitudes through theE‐Fregion electrodynamic coupling.