HR: 14:20h
AN: SM52C-03 INVITED     [PDF]
TI: On the Relation Between the Ring Current and Sub-Auroral Electric Fields and the Plasmasphere
AU: * Brandt, P C
EM: pontus.brandt@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Goldstein, J
EM: jgoldstein@swri.edu
AF: Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238 United States
AU: Fok, M
EM: mei-ching.fok@gsfc.nasa.gov
AF: Goddard Space Flight Center, MC692, Greenbelt, md 20771 United States
AU: Foster, J C
EM: jcf@haystack.mit.edu
AF: Haystack Observatory, Route 40, Westford, ma 01886 United States
AU: Roelof, E C
EM: ed.roelof@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Mitchell, D G
EM: donald.mitchell@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: Anderson, B J
EM: brian.anderson@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AU: DeMajistre, R
EM: robert.demajistre@jhuapl.edu
AF: The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 United States
AB: It has been known that a strong poleward electric field is created in the evening sector at sub-auroral latitudes during mainphases of geomagnetic storms (Galperin et al., 1981). Recently, ground observation efforts from Millstone Hill Radar, GPS receiver stations have related these phenomena to high sunward flow velocities and enhanced electron densities in a narrow latitudinal band at sub-auroral latitudes, Sub-Auroral Polarization Streams (SAPS) and directly related them to the so-called plasmaspheric drainage plume (Foster et al.). Model tests with the Comprehensive Ring Current Model (CRCM) by M. -C. FOk have shown that the formation of the inospheric poleward electric fields in the SAPS regin are an effect of (1) enhanced Region 2 (R2) field-aligned currents (FAC), and (2) the existence of a Pedersen currents that flow poleward from the dusk R2 FACs to high latitudes through a low conductance gap. Goldstein et al. have shown the effect of the SAPS on the plasmasphere and found that it strips of the outer layers of the evening plasmapause pointing at the effects of the SAPS formation. It appears that SAPS are related to the formation of strong pressure gradients in the ring current and plasma sheet which is consistent with enhanced the R2 FACs. To illuminate the cause/driver for the SAPS, we will investigate the relation with the ring current by utilizing field-aligned current (FAC) observations from magnetometers on board Iridium, total electron content (TEC) maps from GPS receivers, DMSP passes and global proton pressure distributions derived from energetic neutral atom (ENA) data from the high energy neutral atom (HENA) imager on board image together with model runs of the CRCM.
DE: 2708 Current systems (2409)
DE: 2712 Electric fields (2411)
DE: 2730 Magnetosphere--inner
DE: 2736 Magnetosphere/ionosphere interactions
DE: 2778 Ring current
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting