Auroral turbulence of the ionospheric convection

The formation of the two-dimensional auroral structures in the cold ionospheric-magnetospheric plasma under convection has been considered. The convection inhomogeneity leads to appearance of the currents across and along the magnetic field lines. The field-aligned currents flowing from the ionosphere into the magnetosphere create positive feedback between magnetospheric and ionospheric perturbations. The ionosphere is assumed as a thin conductive layer, and the processes of ionization and recombination of the charged particles have been considered. The ionospheric processes have been considered as non-linear. In the magnetosphere the linear approximation has been used. The linear equation for the Alfven waves propagating along the magnetic field from the ionosphere to the magnetosphere has been solved with the realistic change of the velocity along the magnetic field lines. It has been found that for moderately disturbed conditions the integral Hall conductivity is equal to 8 S, rise time of auroral disturbances to scale the across the magnetic field of 1 km is ~60 s. The disturbances at the smaller scale have developed faster. The thermal motion of particles in the ionosphere leads to weakening and even suppressing the development of ionospheric disturbances.