Ionosonde Observations of Spread F and Spread Es at Low and Middle Latitudes during the Recovery Phase of the 7–9 September 2017 Geomagnetic Storm

This study presents observations of nighttime spread F/ionospheric irregularities and Es at low middle latitudes in the South East Asia longitude China sectors during recovery phase 7–9 September 2017 geomagnetic storm. In this study, multiple observations, including a chain three ionosondes located about 100°E, Swarm satellites, Global Navigation Satellite System (GNSS) ROTI maps, were used to development process evolution characteristics latitudes. Interestingly, F intense simultaneously observed by phase. Moreover, associated ionospheric could be satellites ground-based GNSS TEC. Nighttime might due off-vertical reflection echoes from large-scale tilts bottom ionosphere. addition, we found that periods disturbance ionosphere are ~1 h ZHY station, ~1.5 LSH station PUR respectively. It suggested produced LSTIDs (Large scale Traveling Ionospheric Disturbances), which induced high-latitude energy inputs Furthermore, receivers caused local electric field LSTIDs.