Ionospheric currents during geomagnetic storms and substorms
Understanding the detailed spatial and temporal dynamics of the space environment is the key task in the basic solar-terrestrial research.
This is inevitably related to the success in providing space weather forecasts to protect vulnerable technological systems. For example,
power grids can be compromised by geomagnetically induced currents (GIC) that are created during large auroral storms.
In this project we study the spatial and temporal variations of ionospheric current systems during major geomagnetic disturbances, such
as storms and substorms. As currents are most easily detected by the magnetic fields they create, we use data from magnetometers
onboard satellites at low Earth orbit as well as on the ground around the auroral oval. Our results will pave way to more accurate
predictions of auroral activity and GICs.
This project is a collaborative effort by researchers at the university of Oulu and the Finnish Meteorological Institute.
Project coordinatorUniversity of Oulu
Apatenkov S.V., V.A. Pilipenko, E.I. Gordeev, A. Viljanen, L. Juusola, V.B. Belakhovsky, Ya.A. Sakharov and V.N. Selivanov: "Auroral omega bands are a significant cause of large geomagnetically induced currents", Geophys. Res. Lett., http://dx.doi.org/10.1029/2019GL086677, 2020.
Cai L., S. Oyama, A. Aikio, H. Vanhamäki and I. Virtanen: "Fabry-Perot interferometer observations of thermospheric horizontal winds during magnetospheric substorms", J. Geophys. Res. Space, http://dx.doi.org/10.1029/2018JA026241, 2019.
Dimmock A.P., L. Rosenqvist, J.-O. Hall, A. Viljanen, E. Yordanova, I. Honkonen, M. André and E.C. Sjöberg: "The GIC and geomagnetic response over Fennoscandia to the 7‐8 September 2017 geomagnetic storm", Space Weather, http://dx.doi.org/10.1029/2018SW002132, 2019.
Dimmock A.P., L. Rosenqvist, D. Welling, A. Viljanen, I. Honkonen, R.J. Boynton and E. Yordanova: "On the regional variability of dB/dt and its significance to GIC", Space Weather, http://dx.doi.org/10.1029/2020SW002497, 2020.
Juusola L., H. Vanhamäki, A. Viljanen and M. Smirnov: "Induced currents due to 3D ground conductivity play a major role in the interpretation of geomagnetic variations", Ann. Geophys., http://dx.doi.org/10.5194/angeo-38-983-2020, 2020.
Oyama S., A. Shinbori, Y. Ogawa, M. Kellinsalmi, T. Raita, A. Aikio, H. Vanhamäki, et al. (23 authors), "An ephemeral red arc appeared at 68o MLat at a pseudo breakup during geomagnetically quiet conditions", J. Geophys. Res., http://dx.doi.org/10.1029/2020JA028468, 2020.
Palmroth M., M. Grandin, M. Helin, P. Koski, A. Oksanen, M.A. Glad, R. Valonen, K. Saari, E. Bruus, J. Norberg, A. Viljanen, K. Kauristie and P.T. Verronen: "Citizen scientists discover a new auroral form: Dunes provide insight into the upper atmosphere", AGU Advances, http://dx.doi.org/10.1029/2019AV000133, 2020.
Trenchi L. , K. Kauristie, S. Käki, Heikki Vanhamäki et al.: "ESA Field-Aligned Currents - Methodology Intercomparison Exercise", chapter 8 in Ionospheric Multi-Spacecraft Analysis Tools, M. Dunlop and H. Lühr (eds.), http://dx.doi.org/10.1007/978-3-030-26732-2_8, 2020.
Vanhamäki H. and L. Juusola: "Introduction to Spherical Elementary Current Systems", chapter 2 in Ionospheric Multi-Spacecraft Analysis Tools, M. Dunlop and H. Lühr (eds.), http://dx.doi.org/10.1007/978-3-030-26732-2_2, 2020.
Vanhamäki H., L. Juusola, K. Kauristie, A. Workayehu and S. Käki: "Spherical Elementary Current Systems applied to Swarm data", chapter 3 in Ionospheric Multi-Spacecraft Analysis Tools, M. Dunlop and H. Lühr (eds.), http://dx.doi.org/10.1007/978-3-030-26732-2_3, 2020.
Vanhamäki H., A. Maute, P. Alken and H. Liu: "Dipolar elementary current systems for ionospheric current reconstruction at low and middle latitudes", Earth Planets Space, http://dx.doi.org/10.1186/s40623-020-01284-1, 2020.
Waters C.L., B.J. Anderson, D.L. Green, H. Korth, R.J. Barnes and H. Vanhamäki: "Science data products for AMPERE", chapter 7 in Ionospheric Multi-Spacecraft Analysis Tools, M. Dunlop and H. Lühr (eds.), http://dx.doi.org/10.1007/978-3-030-26732-2_7, 2020.
Workayehy A., H. Vanhamäki, and A. Aikio: "Field-aligned and horizontal currents in the Northern and Southern hemispheres from the Swarm satellite", J. Geophys. Res., http://dx.doi.org/10.1029/2019JA026835, 2019.
Workayehu A., H. Vanhamäki and A. Aikio: "Seasonal effect on hemispheric asymmetry in ionospheric horizontal and field-aligned currents", J. Geophys. Res., http://dx.doi.org/10.1029/2020JA028051, 2020.