Ionospheric conductivity effects on electric field penetration from atmosphere into ionosphere

Denisenko V.V.1, Ampferer M.2, Biernat H.K.3
  1. Institute of Computational Modeling RAS SB, Krasnoyarsk, Russia
  2. Karl-Franzens-University, Graz, Austria
  3. Space Research Institute AAS, Graz, Austria

The classic approach to calculate the electric field penetration from the Earth’s surface into the ionosphere
is the solution of the stationary equation of conductivity. Field penetration is determined by the spatial
distribution of conductivity in the atmosphere and ionosphere. The conductivity of the atmosphere is scalar
and in the ionosphere it becomes a strongly anisotropic tensor. To simplify the model, we suppose that such
a sudden change occurs at some height above which the field aligned conductivity becomes infinite. This
approximation corresponds to usual introduction of integral conductivity of the ionosphere. Such a model of
the ionosphere is equivalent to a special upper boundary condition in the problem for the atmospheric electric
field. It can be derived from the charge conservation law. We also consider the magnetic field to be vertical
We showed that the magnitude of the ionospheric electric field penetrated from the Earth’s surface is inversely
proportional to the value of the integral ionospheric Pedersen conductance. So its typical value in the day-time
is about a hundred times less than at night. The both values in our model are much smaller than those in some
known models, which do not take ionospheric conductivity into account.