Skip to main content


We’d like to understand how you use our websites in order to improve them. Register your interest.

Using global magnetospheric models for simulation and interpretation of Swarm external field measurements


We have used a global model of the solar wind magnetosphere interaction to model the high latitude part of the external contributions to the geomagnetic field near the Earth. The model also provides corresponding values for the electric field. Geomagnetic quiet conditions were modeled to provide simulated external contributions relevant for internal field modeling. These have proven very valuable for the design and planning of the upcoming multi-satellite Swarm mission. In addition, a real event simulation was carried out for a moderately active time interval when observations from the Ørsted and CHAMP sattelites were available. Comparisons between the simulation results and the satellite observations for this event demonstrate the current level of validity of the global model. We find that the model reproduces quite well the region 1 current system and nightside region 2 currents whereas it consistently underestimates the dayside region 2 currents and overestimates the horizontal ionospheric closure currents in the dayside polar cap. Furthermore, with this example we illustrate the great benefit of utilizing the global model for the interpretation of Swarm external field observations and, likewise, the potential of using Swarm measuremnets to test and improve the global model.


  1. Backus, G., Poloidal and toroidal fields in geomagnetic field modeling, Rev. Geophys., 24, 75, 1986.

  2. De Zeeuw, D. L., S. Sazykin, R. A. Wolf, T. I. Gombosi, A. J. Ridley, and G. Toth, Coupling of global MHD code and an inner mag-netospheric model: Initial results, J. Geophys. Res., 109, A12219, doi:10.1029/2003JA010366, 2004.

  3. Engels, U. and N. Olsen, Computation of magnetic fields within source regions of ionospheric and magnetospheric currents, J. Atm. Sol.-Terr. Physics, 60, 1585, 1998.

  4. Friis-Christensen, E., H. Lühr, and G. Hulot, Swarm: A constellation to study the Earth’s magnetic field, Earth Planets Space, 58, this issue, 351–358, 2006.

  5. Friis-Christensen, E., Y. Kamide, A. D. Richmond, and S. Matshusita, Interplanetary magnetic field control of high-latitude electric fields and currents determined from Greenland magnetometer data, J. Geophys. Res., 90, 1325, 1985.

  6. Iijima, T. and T. A. Potemra, The amplitude distribution of field-aligned currents at northern high latitudes observed by Triad, J. Geophys. Res., 81, 2165, 1976.

  7. Keller, K. A., M. Hesse, M. Kuznetsova, L. Rastätter, T. Moretto, T. I. Gombosi, and D. L. DeZeeuw, Global MHD modeling of the impact of a solar wind pressure change, J. Geophys. Res., 107, 1126, 2002.

  8. Kelley, M. C., The Earth’s Ionosphere, Academic Press, New York, 1989.

  9. Knight, S., Parallel electric fields, Planet. Space Sci., 21, 741, 1972.

  10. Korth, H., B. J. Anderson, M. J. Wiltberger, J. G. Lyon, and P. C. Anderson, Intercomparison of ionospheric electrodynamics from the Iridium constellation with global MHD simulations J. Geophys. Res., 109, doi:10.1029/2004JA010428, 2004.

  11. Lotko, W., Inductive magnetosphere-ionosphere coupling, J. Atm. Sol.-Terr. Physics, 66, 1443, 2004.

  12. Moen, J. and A. Brekke, The solar flux influence on quiet time conductances in the auroral ionosphere, Geophys. Res. Lett., 20, 971, 1993.

  13. Neubert, T., M. Mandea, G. Hulot, R. von Frese, F Primdahl, J. L. Jørgensen, E. Friis-Christensen, P. Stauning, N. Olsen, and T. Risbo, Ørsted satellite captures high-precision geomagnetic field data, EOS, 82, 81, 2001.

  14. Ohtani, S.-I. and J. Raeder, Tail current surge: New insights from a global MHD simulation and comparison with satellite observations, J. Geo-phys. Res., 109, doi:10.1029/2002JA009750, 2004.

  15. Papitashvili, V. O., F. Christiansen, and T. Neubert, A new model of field-aligned currents derived from high-precision satellite magnetic field data, Geophys. Res. Lett., 29, No. 14, doi:10.1029/2001GL014207, 2002.

  16. Raeder, J., Global Geospace Modeling: Tutorial and review, in Space Plasma Simulations, edited by J. Buchner, C. T. Dunn, and M. Scholer, 615 of Lecture notes in physics, Springer Verlag, Berlin, 2003.

  17. Raeder, J., R. J. Walker, and M. Ashour-Abdalla, The structure of the distant geomagnetic tail during long periods of northward IMF, Geophys. Res. Lett., 22, 349, 1995.

  18. Raeder, J., J. Berchem, M. Ashour-Abdalla, L. A. Frank, W. R. Paterson, K. L. Ackerson, S. Kokubun, and J. A. Slavin, Boundary layer formation in the magnetotail: Geotail observations and comparisons with a global MHD simulation, Geophys. Res. Lett., 24, 951, 1997.

  19. Raeder, J., J. Berchem, and M. Ashour-Abdalla, The geospace environment modeling grand challenge: Results from a global geospace circulation model, J. Geophys. Res., 103, 14787, 1998.

  20. Raeder, J., Y. Wang, and T. Fuller-Rowell, Geomagnetic storm simulation with a coupled magnetosphere-ionosphere-thermosphere model, in Space Weather, AGU Geophys. Monogr. Ser, edited by P. Song, G. Sis-coe, and H. J. Singer, Vol. 125, pp. 377, American Geophysical Union, 2001.

  21. Reigber, C., H. Lühr, and P. Schwintzer, CHAMP Mission Status, Advances in Space Research, 30(2), 129, 2002.

  22. Ridley, A. J., A. D. Richmond, T. I. Gombosi, D. L. De Zeeuw, and C. R. Clauer, Ionospheric control of the magnetospheric configuration: Thermospheric neutral winds, J. Geophys. Res., 108(A8), 1328, doi:10.1029/2002JA009464, 2003.

  23. Ritter, P. and H. Lühr, Curl-B technique applied to Swarm constellation for determining field-aligned currents, Earth Planets Space, 58, this issue, 463–476, 2006.

  24. Robinson, R. M., R. R. Vondrak, K. Miller, T. Dabbs, and D. Hardy, On calculating ionospheric conductances from the flux and energy of precipitating electrons, J. Geophys. Res., 92, 2565, 1987.

  25. Ruohoniemi, J. M., S. G. Shepherd, and R. A. Greenwald, The response of the high-latitude ionosphere to IMF variations, J. Atm. Sol.-Terr. Physics, 64, 159, 2002.

  26. Sabaka, T. J., N. Olsen, and R. A. Langel, A comprehensive model of the quiet-time near-Earth magnetic field: Phase 3, Geophys. J. Int., 151, 32, 2002.

  27. Stern, D. P., Representation of magnetic fields in space, Rev. Geophys., 14, 199, 1976.

  28. Vennerstrøm, S., T. Moretto, N. Olsen, E. Friis-Christensen, A. M. Stampe, and J. F. Watermann, Field-aligned currents in the dayside cusp and polar cap region during northward IMF, J. Geophys. Res., 107, doi:10.1029/2001JA009162, 2002.

  29. Vennerstrøm, S., T. Moretto, L. Rastätter, and J. Raeder, Field-aligned currents during northward interplanetary magnetic field: Morphology and causes, J. Geophys. Res., 110(A6), doi:10.1029/2004JA010802, 2005.

  30. Vennerstrom, S., T. Moretto, L. Rastätter, and J. Raeder, Modeling and analysis of solar wind generated contributions to the near-Earth magnetic field, Earth Planets Space, 58, this issue, 451–461, 2006.

  31. Weimer, D. R., Models of high-latitude electric potentials derived with a least error fit of spherical harmonic coefficients, J. Geophys. Res., 100, 19, 595, 1995.

  32. Weimer, D. R., An improved model of ionospheric electric potentials including substorm perturbations and application to the GEM November 24, 1996 event, J. Geophys. Res., 106, 407, 2001.

Download references

Author information



Corresponding author

Correspondence to T. Moretto.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Moretto, T., Vennerstrøm, S., Olsen, N. et al. Using global magnetospheric models for simulation and interpretation of Swarm external field measurements. Earth Planet Sp 58, 439–449 (2006).

Download citation

Key words

  • Ionospheric currents
  • field-aligned currents
  • global magnetospheric simulation
  • low-altitude satellites