A Comparison of Ionospheric Conductances between EISCAT and DMSP in Different Auroral Precipitation Conditions
Abstract
Energetic particle precipitation has a strong impact on the distribution of ionospheric conductances in the high-latitude ionosphere. Several studies have developed empirical models to obtain the Pedersen and Hall conductances, which are affected by auroral precipitation. Perhaps the most widely used model are the Robinson formulas, which give the conductances as function of integral energy flux and average energy of the precipitating electrons. In this study, we validate the Robinson formulas in different auroral conditions using data from the EISCAT incoherent scatter radars and the DMSP satellites. The validation is carried out by first searching conjugate DMSP satellite overpasses in the vicinity of EISCAT mainland or Svalbard sites. Pedersen and Hall conductances are then calculated from DMSP/SSJ energetic particle measurements using the Robinson formulas, and from the EISCAT measurements using theoretical equations. We compare the two kinds of conductances in four conditions: mono-energetic electrons, central plasma sheet (CPS) electrons without energetic ions, CPS electrons with energetic ions, and pure energetic ions, respectively. The results show that the conductances calculated with the Robinson formulas are correlated best with the EISCAT results when CPS electrons without energetic ions dominate. When the ion precipitation exists, the two kinds of conductances are less correlated. The ion precipitation adds an additional effect on the ionospheric conductances. About 1-7 mhos of the Pedersen conductances and 2-8 mhos of the Hall conductances can be contributed by ion precipitations. Therefore, the ionospheric conductances can be underestimated if only the Robinson formulas are used.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFMSA21B..01W