Ionospheric absorption, typical ionization, conductivity, and possible synoptic heating parameters in the upper atmosphere

Abstract

Relations for the average energetic particle heating and the typical Hall and Pedersen conductances, as functions of the ground‐based HF radio absorption, are determined. Collis and coworkers used the geosynchronous GEOS 2 particle data to relate or “calibrate” the auroral absorption on the same magnetic field lines with five levels of D region ionization. These ionospheric models are related to a Chapman layer that extends these models into the E region. The average energetic particle heating is calculated for each of these models using recent expressions for the effective recombination coefficient. The corresponding height‐integrated heating rates are determined and related to the absorption with a quadratic expression. The average Hall and Pedersen conductivities are calculated for each of the nominal absorption ionospheric models. The corresponding height‐integrated conductances for night‐time conditions are determined and related to the absorption. Expressions for these conductances during disturbed sunlit conditions are also determined. These relations can be used in conjunction with simultaneous ground‐based riometric and magnetic observations to determine the average Hall and Pedersen currents and the Joule heating. The typical daily rate of temperature increase in the mesosphere for storm conditions is several 10 K for both the energetic particle and the Joule heating. The increasing importance of these parameters of the upper and middle atmospheres is discussed. It is proposed that northern hemisphere ionospheric, current, and heating synoptic models and parameters be investigated for use on a regular basis.

On the relationship between auroral absorption, electrojet currents and plasma convection

“…This was confirmed experimentally by Walker and Bhatnagar (1989) and, more recently, by Senior et al (2007). The Hall conductance H was shown to be more strongly related to CNA than Pedersen conductance P and the correlation between H and CNA was shown to vary with magnetic local time or MLT .…”

First results from imaging riometer installed at Indian Antarctic station Maitri

“…More energetic electrons (>20 keV) enhance the electron densities in the lower E-and D-regions (<100 km) of ionosphere. Walker and Bhatnagar (1989) confirmed experimentally that auroral absorption and electrical conductances are closely related. Moreover, CNA depends indirectly on the electric field.…”

Self‐Consistent Modeling of Electron Precipitation and Responses in the Ionosphere: Application to Low‐Altitude Energization During Substorms

“…The conductivity sublayer actually has been mentioned by Walker and Bhatnagar (1989), who derived relations of upper atmosphere particle heating and Hall and Pedersen conductances as function of the ground-based radio absorption. The conductivity sublayer actually has been mentioned by Walker and Bhatnagar (1989), who derived relations of upper atmosphere particle heating and Hall and Pedersen conductances as function of the ground-based radio absorption.…”

“…The above simulation results of the appearance of Pedersen conductivity sublayer and its eastward transport are consistent with earlier studies. The conductivity sublayer actually has been mentioned by Walker and Bhatnagar (1989), who derived relations of upper atmosphere particle heating and Hall and Pedersen conductances as function of the ground-based radio absorption. With the inclusion of energetic particle flux, D region exhibits a secondary peak in the Pedersen conductivity.…”