Gradient-Based Analysis of the Planar Trend Model for the Southern Hemisphere
11th International Conference on Recent Advances in Air and Space Technologies, Conference Program, RAST 2026, İstanbul, Türkiye, 13 - 15 Mayıs 2026, (Tam Metin Bildiri)
- Yayın Türü: Bildiri / Tam Metin Bildiri
- Doi Numarası: 10.1109/rast69551.2026.11672595
- Basıldığı Şehir: İstanbul
- Basıldığı Ülke: Türkiye
- Anahtar Kelimeler: antractic circumpolar current, gradient, midlatitude ionosphere, total electron content
- Hacettepe Üniversitesi Adresli: Evet
Özet
The ionosphere exhibits a spatiotemporally varying structure, influenced by hydrodynamic and atmospheric processes in a complex manner. Comprehending these interactions is crucial for both the characterization of the ionospheric trend behavior and ensuring reliable operation of navigation systems and wireless communication systems. In this study, the daytime- nighttime dissimilarity for the gradient of the planar trend model is investigated for 12 Southern Hemisphere regions, which are primarily located over the path of the Antarctic Circumpolar Current (ACC). The gradient of the planar trend model is initially computed by using the monthly bi-hourly median planar trend model coefficients. Following it, the daytime-nighttime dissimilarity of the gradient is quantified by the Dissimilarity measure (DM) for all months and all regions under High Solar Activity (HSA) conditions. Regarding the obtained results, two distinct annual behaviors are primarily observed. The first one shows higher dissimilarity in January-February and November- December, with a notably depleted level from May to September, whereas the other one exhibits a peak level from May to July and shows a smaller dissimilarity from January to March and October to December. The first characteristic is noted to occur for Southern Pacific regions, and the other behavior is noted to be prevalent for Southern Indian Ocean and Atlantic regions. Furthermore, transitions between these behaviors are noted to occur over the areas for which the topographical structures have a notable impact on both direction and intensity of ACC.