Articles | Volume 43, issue 2
https://doi.org/10.5194/angeo-43-447-2025
https://doi.org/10.5194/angeo-43-447-2025
Regular paper
 | 
27 Aug 2025
Regular paper |  | 27 Aug 2025

Small-scale and mesoscale field-aligned auroral current structures: their spatial and temporal characteristics deduced by the Swarm constellation

Hermann Lühr and Yun-Liang Zhou

Related authors

Properties of large-amplitude kilometer-scale field-aligned currents at auroral latitudes, as derived from Swarm satellites
Yun-Liang Zhou and Hermann Lühr
EGUsphere, https://doi.org/10.5194/egusphere-2025-1961,https://doi.org/10.5194/egusphere-2025-1961, 2025
Short summary

Cited articles

Ala-Lahti, M., Pulkkinen, T. I., Pfau-Kempf, Y., Grandin, M., and Palmroth, M.: Energy flux through the magnetopause during flux transfer events in hybrid-Vlasov 2D simulations, Geophys. Res. Lett., 49, e2022GL100079, https://doi.org/10.1029/2022GL100079, 2022. 
Anderson, B. J., Korth, H., Waters, C. L., Green, D. L. Merkin, V. G., Barnes, R. J., and Dyrud, L. P.: Development of large-scale Birkeland currents determined from the active magnetosphere and planetary electrodynamics experiment, Geophys. Res. Lett., 41, 3017–3025, https://doi.org/10.1002/2014GL059941, 2014. 
Finlay, C. C., Kloss, C., Olsen, N., Hammer, M., Toeffner-Clausen, L., Grayver, A., and Kuvshinov, A.: The CHAOS-7 geomagnetic field model and observed changes in the South Atlantic Anomaly, Earth Planets Space, 72, 156, https://doi.org/10.1186/s40623-020-01252-9, 2020. 
Forsyth, C., Rae, I. J., Mann, I. R., and Pakhotin, I. P.: Identifying intervals of temporally invariant field-aligned currents from Swarm: Assessing the validity of single-spacecraft methods, J. Geophys. Res.-Space Phys., 122, 3411–3419, https://doi.org/10.1002/2016JA023708, 2017. 
Friis-Christensen, E., McHenry, M. A., Clauer, C. R., and Venneström, S.: Ionospheric traveling convection observed near the polar cleft: a triggered response to sudden changes in the solar wind, Geophys. Res. Lett., 15, 253–256, 1988. 
Download
Short summary
The study makes use of magnetic field data from the closely spaced Swarm A and C spacecraft during the counter-rotating orbit phase. It allows investigating the spatial and temporal correlation lengths of small-scale and mesoscale FAC (field-aligned current) structures at auroral latitudes. Stationarity features of small-scale FACs (10–50 km scale size) are temporal length < 18 s and correlation length < 12 km. For mesoscale FACs (75–220 km scales) we obtain a stability of > 40 s and correlation length > 20 km.
Share