Abstract
The energy deposition from ring current ions into the high density
“cold” plasma of the ionosphere and plasmasphere is analyzed, based on
a Comprehensive Inner Magnetosphere-Ionosphere (CIMI) simulation of the
2015 October 7 storm. In this re-examination of ring current heating
generating the observed O$^+$ shell in the outer plasmasphere
[1], the Naval Research Laboratory (NRL) Sami3 is Also a Model of
the Ionosphere (SAMI3) ionosphere/plasmasphere code [2] is used to
simulate the effect of ring current heating on the ionosphere. We find
that energy is deposited at altitudes as low as 100 km. We show that
heating along the entirety of any given field line, both in the
ionosphere and plasmasphere, contributes to the heating effect and
subsequent cold O$^+$ outflows. We further show that, relative to
the heating of the plasmasphere, the direct heating of the ionosphere by
ring current ions produces only a small contribution to the thermal
O$^+$ outflow that forms the O$^+$ shell. [1] Krall, J.,
J. D. Huba, and M.-C. Fok (2020), Does ring current heating generate the
observed O$^+$ shell?, Geophys. Res. Lett., 47, e2020GL088419,
doi:10.1029/2020GL088419 [2] Huba, J., and J. Krall (2013), Modeling
the plasmasphere with SAMI3, Geophys. Res. Lett., 40, 6–10,
doi:10.1029/2012GL054300 Research supported by NRL base funds and NASA.