HR: 15:45h
AN: SA14A-02    [Abstracts]
TI: Solar EUV and Geomagnetic Storm Control Of The Ionosphere-Thermosphere System
AU: * Mannucci, A J
EM: Anthony.J.Mannucci@jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 138-307, Pasadena, CA 91109
AU: Tsurutani, B T
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 138-307, Pasadena, CA 91109
AU: Hajj, G A
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 138-307, Pasadena, CA 91109
AU: IIjima, B A
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 138-307, Pasadena, CA 91109
AU: Komjathy, A
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 138-307, Pasadena, CA 91109
AB: Recent studies using ionospheric total electron (TEC) content data from ground and space-borne GPS receivers suggest a prompt daytime TEC increase at low and middle latitudes during the early main phase of intense geomagnetic storms. GPS and other data, such as DMSP electric fields and ground-based magnetometers, suggest the presence of zonal electric fields near the magnetic equator contributing to vertical plasma uplift and dramatic changes in low and mid-latitude ionospheric structure. Recent analysis of several events over the past few years suggests this early positive daytime ionospheric response is a common feature, but the degree of response and its relation to interplanetary parameters is not well characterized. We will present GPS data from these same intense events, focusing on the first three hours after interplanetary coronal mass ejections (ICMEs) reach the magnetosphere, as determined from ACE data. Using the broad local time coverage of the global network of GPS ground receivers, and the continuous latitude sampling of space-borne GPS receivers, we will elucidate the relationship between the low and mid-latitude TEC response and parameters describing the ICME interplanetary parameters, such as the z-component of the interplanetary magnetic field (Bz). Thermospheric feedback mechanisms, for example changes to winds and neutral composition on the dayside, will be considered in the analysis.
DE: 2411 Electric fields (2712)
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 2435 Ionospheric disturbances
SC: SPA-Aeronomy [SA]
MN: 2005 Joint Assembly