Premium
Consequences of a saturated convection electric field on the ring current
Author(s) -
Liemohn M. W.,
Kozyra J. U.,
Hairston M. R.,
Weimer D. R.,
Lu G.,
Ridley A. J.,
Zurbuchen T. H.,
Skoug R. M.
Publication year - 2002
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2001gl014270
Subject(s) - ring current , solar wind , magnetosphere , geomagnetic storm , physics , geophysics , interplanetary magnetic field , interplanetary spaceflight , electric field , convection , computational physics , atmospheric sciences , saturation (graph theory) , mechanics , magnetic field , quantum mechanics , mathematics , combinatorics
Results from kinetic simulations of hot ion transport in the inner magnetosphere are used to show that the ring current energy content must have a nonlinear (asymptotic) coupling relationship to extreme solar wind conditions due to saturation of the near‐Earth convection electric field E y, conv (defined as a function of cross polar cap potential ΔΦ PC ). This study examines the Bastille Day magnetic storm (July 14–17, 2000), where the z‐component of the interplanetary magnetic field reached −58 nT and the solar wind speed exceeded 1100 km s −1 . A large discrepancy in the modeled ΔΦ PC confirms a nonlinear response of the high‐latitude potential during this event. It is found that this nonlinearity of E y, conv is necessary to obtain reasonable agreement between the simulation results and the observed geoeffectiveness (Dst) of the storm.