Occurrence and Characteristics of Traveling Ionospheric Disturbances in the Antarctic Peninsula Region

Abstract

A statistical picture of the occurrence and characteristics of Traveling Ionospheric Disturbances (TIDs) over the Antarctic Peninsula is established using Global Navigation Satellite System Total Electron Content and High Frequency sounding observations. The measured parameters of the majority of the disturbances allow classifying them as medium scale TIDs (MSTIDs). Overall, the observed climatology of ionospheric disturbances in the Antarctic Peninsula region varies significantly with the season and makes it possible to differentiate two major types of the disturbances: winter daytime and summer nighttime, based on their occurrence periods and characteristics. During the Antarctic summer period, the disturbances are present mainly during the nighttime and morning hours, when the background plasma density is at maximum (due to Weddell Sea Anomaly). These disturbances predominantly propagate northwestward and their occurrence probability is well correlated with the sporadic E layer observations, suggesting that these are electrified MSTIDs. During the winter, the TID events are almost exclusively observed during the daytime. The propagation direction of the disturbances during the daytime shows a strong correlation with the background neutral wind direction in the thermosphere. A possible mechanism for this effect is wind filtering of the Atmospheric Gravity Waves originating in the troposphere, which indicates that their source is in the lower atmosphere. The periods of the TIDs also significantly differ between the seasons. Wintertime TIDs have noticeably shorter periods (10–50 min) than those observed during other parts of the year (30–140 min), which also likely reflects the fact that the two types of TIDs are generated by different physical mechanisms.

Occurrence and Characteristics of Medium‐Scale Traveling Ionospheric Disturbances Observed by BeiDou GEO Satellites Over Hong Kong

“…These disturbances significantly impact the performance and reliability of services such as navigation positioning, shortwave communication, and high‐frequency radar, particularly in low‐latitude regions (Fiori et al., 2022). In order to minimize the impact of MSTIDs in the mentioned applications, understanding the climatological patterns and characteristics of recent TIDs in low‐latitude regions is crucial (Paznukhov et al., 2022). Therefore, in this study, BeiDou GEO observation data are utilized for the first time to analyze the propagation characteristics of MSTIDs in Hong Kong during the rising phase of solar activity.…”