HR: 0800h
AN: SA21A-0268    [Abstracts]
TI: Unusual topside ionospheric density response to the November 2003 superstorm
AU: * Yizengaw, E
EM: ekassie@igpp.ucla.edu
AF: Institute of Geophysics and Planetary Physics, University of California Los Angeles, Los Angeles, CA 90095 United States
AU: Moldwin, M B
EM: mmoldwin@igpp.ucla.edu
AF: Institute of Geophysics and Planetary Physics, University of California Los Angeles, Los Angeles, CA 90095 United States
AU: Mannucci, A J
EM: Tony.Mannucci@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Komjathy, A
EM: Attila.Komjathy@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AB: We use observations from a variety of different ground and space-based instruments, including ionosonde, ground and space-based Global Positioning System (GPS) receivers, magnetometers, and the solar wind data from the Advanced Composition Explorer (ACE), to examine the response of the ionospheric F2-layer height during the November 2003 superstorm. We found that the topside ionosphere responded unusually to the November 20, 2003 severe storm. While ground-based GPS receivers observed a large enhancement in dayside TEC, the Low-Earth orbiting (~400 km) CHAMP satellite did not show any sign of dayside TEC enhancement. The real-time vertical density profiles, constructed from ground based GPS TEC using a tomographic reconstruction technique, clearly revealed that the ionospheric F2-layer peak height had been depressed down to lower altitudes. Ionospheric F-layer peak height (hmF2) from the nearby ionosonde stations over Europe also showed that the dayside F2-layer peak height was below 350 km, which is below the orbiting height of CHAMP, on 20 November 2003. The vertical E x B drift (estimated from ground-based magnetometer equatorial electrojet delta H) did show dayside strong downward drifts, which may be attributed to the ionospheric disturbance dynamo electric field produced by the large amount of energy dissipation into high latitude regions. This storm demonstrates that care has to be taken in interpreting data from LEO satellites.
DE: 2411 Electric fields (2712)
DE: 2435 Ionospheric disturbances
DE: 2441 Ionospheric storms (7949)
DE: 2443 Midlatitude ionosphere
DE: 2481 Topside ionosphere
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005