A medium-scale travelling ionospheric disturbance (MSTID) was observed concomitantly by SANAE and Halley SuperDARN HF radars during the period 02–06 UT 17 March 2013. The event occurred during a geomagnetically quiet time where no substorm or storm activities were observed. Both radars (at similar geomagnetic latitudes of 61.8⁰S (SANAE) and 62.1⁰S (Halley)) are well placed for observing the sporadic E (Es) region associated with the ionospheric trough around midnight during quiet geomagnetic conditions. F region electrodynamics and electrical coupling between E and F regions are one of the important mechanisms for the generation of nighttime MSTIDs. This is thought to be the generation mechanism in this study. We analysed the radar data using multitaper method (MTM). Multiple windowing mitigates spectral leakage and bias. The orthogonality of the tapers allows for confidence levels of peaks to be determined. The results from both radars show an MSTID with a period of approximately 23 min propagating at a speed ~280 ms⁻¹ (SANAE) and 178 ms⁻¹ (Halley) in the Southeast direction. An upper limit of ~55 kW was estimated to be dissipated by Joule heating due to the MSTID over an area where it was detected by both radars with more than 90% confidence.

2013 年 3 月 2 日至 6 日 UT 2013 年 3 月 2 日至 6 日期间，SANAE 和哈雷 SuperDARN HF 雷达同时观测到中尺度移动电离层扰动 (MSTID)。该事件发生在未观测到亚暴或风暴活动的地磁安静时期。两个雷达（在相似的地磁纬度 61.8 ⁰ S (SANAE) 和 62.1 ⁰S (Halley)) 非常适合在安静的地磁条件下观测午夜前后与电离层槽相关的零星 E (Es) 区域。F区电动力学和E区与F区之间的电耦合是夜间MSTID产生的重要机制之一。这被认为是本研究中的生成机制。我们使用多锥方法（MTM）分析了雷达数据。多窗口化可减轻频谱泄漏和偏差。锥度的正交性允许确定峰值的置信水平。两部雷达的结果显示，MSTID 以~280 ms ^-1 (SANAE) 和 178 ms ^-1的速度传播，其周期约为 23 分钟（哈雷）在东南方向。由于 MSTID 在两个雷达以超过 90% 的置信度检测到焦耳加热的区域上，估计约 55 kW 的上限被焦耳加热消散。