Open AccessThe Unknown Hydrogen Exosphere: Space Weather Implications
Author(s) -
Krall J.,
Glocer A.,
Fok M.C.,
Nossal S. M.,
Huba J. D.
Publication year - 2018
Publication title -
space weather
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.254
H-Index - 56
ISSN - 1542-7390
DOI - 10.1002/2017sw001780
Subject(s) - exosphere , plasmasphere , ionosphere , geomagnetic storm , space weather , magnetosphere , ring current , earth's magnetic field , storm , atmospheric sciences , hydrogen , geophysics , meteorology , physics , environmental science , ion , magnetic field , quantum mechanics
Recent studies suggest that the hydrogen (H) density in the exosphere and geocorona might differ from previously assumed values by factors as large as 2. We use the SAMI3 (Sami3 is Also a Model of the Ionosphere) and Comprehensive Inner Magnetosphere‐Ionosphere models to evaluate scenarios where the hydrogen density is reduced or enhanced, by a factor of 2, relative to values given by commonly used empirical models. We show that the rate of plasmasphere refilling following a geomagnetic storm varies nearly linearly with the hydrogen density. We also show that the ring current associated with a geomagnetic storm decays more rapidly when H is increased. With respect to these two space weather effects, increased exosphere hydrogen density is associated with reduced threats to space assets during and following a geomagnetic storm.