Ground Magnetic Perturbations in the Polar Cap and Cleft: Relationship with the IMF

  • E. Friis-Christensen
Part of the NATO ASI Series book series (ASIC, volume 278)


Average empirical models of the magnetospheric and ionospheric electrodynamic parameters play an important role as a frame of reference and also as boundary conditions for the more advanced dynamical models. Furthermore the empirical models may be used to test our physical models and concepts. With the vast amount of geophysical and solar data which is now available, a number of empirical models have appeared, but the different empirical models are not all comparable due to a difference in experimental methods, averaging techniques, and observing conditions. In this review we will describe various average models of electric fields and currents and compare them with models obtained using ground-based magnetometer measurements. It is our conclusion that the major differences between the models are not primarily due to the different measuring techniques, but can be explained taking the merits and demerits of the different averaging and normalization techniques into consideration. This is important to take into account when trying to understand the physics, which the empirical models represent.


Solar Wind Interplanetary Magnetic Field Magnetic Local Time Convection Pattern Electric Potential Distribution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • E. Friis-Christensen
    • 1
  1. 1.Division of GeophysicsDanish Meteorological InstituteCopenhagenDenmark

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