A unified theory of anomalous resistivity and Joule heating effects in the presence of ionospheric E region irregularities


  • J. -P. St.-Maurice


This paper describes how large-amplitude plasma waves in the E region can simultaneously change the conductivity of the plasma and heat the electrons, and how these two processes are actually related to one another and to overall energy balance requirements. We show how to relate the wave-enhanced transport properties to the turbulent state of the plasma, and, ultimately, to broadband electric field and density fluctuation levels. We point out that in theories for which enhanced diffusion effects are used to saturate the unstable waves, care should be taken not to have wave amplitudes that exceed the limits provided by full turbulence estimates; we use an earlier theory proposed by Ichimaru to obtain such an estimate. We also stress that anomalous diffusion is, at most, two-dimensional, and that the momentum equation is therefore not affected by anomalous diffusion in the magnetic field direction. On the other hand, we show that what little wave energy there is in the magnetic field direction could be important for wave heating purposes. We show how to combine, in general, the parallel wave heating rate and heating produced by the increase in perpendicular conductivity and compare, in that light, various calculations done to date on this subject.