HR: 1340h
AN: SA13A-1077 [Abstracts]
TI: Storm-time ionospheric electron density structures simulated by coupled model runs at mid- and low-latitudes
AU: * Lin, C
EM: clin@nspo.org.tw
AF: National Space Organization, 8F, 9 Prosperity Rd., Hsinchu Science Park, Hsinchu, 30078,
Taiwan
AU: Richmond, A D
EM: richmond@ucar.edu
AF: High Altitude Observatory, National Center for Atmospheric Research, P. O. Box 3000,
Boulder, CO 80307, United States
AU: Bailey, G J
EM: G.Bailey@sheffield.ac.uk
AF: Department of Applied Mathematics, University of Sheffield, Sheffield, S3 7RH, United
Kingdom
AU: Liu, J
EM: jyliu@ss.ncu.edu.tw
AF: Institute of Space Science, National Central University, 300, Jhongda Rd., Jhongli, 32001,
Taiwan
AB:
This study presents theoretical simulations of mid- and low-latitude ionospheric electron density structures
produced by a storm-generated electric field. Various storm-time ionosphere electron density structures, such as
mid- and low-latitude storm enhanced electron density, ionospheric electron density hole, electron density
trough, electron density arches, and storm-generated additional layer (F3 layer), are predicted by coupled NCAR
Thermosphere Ionosphere Electrodynamic General Circulation Model (TIEGCM) and Sheffield University
Plasmasphere Ionosphere Model (SUPIM) runs. Possible physical processes and important drivers responsible
for these storm-produced mid- and low-latitude ionospheric structures are discussed under various simulation
conditions. A storm-time electron density hole may result from uplift of the original F-layer to much higher
altitudes, while a new F-layer is formed at the original F-layer altitude when the photo-ionization process still
operates. If the F-layer uplift occurred during evening hours, when the photo-ionization process becomes much
weaker, an equatorial density trough is then formed. Meanwhile, a super-high F2 layer and/or F3 layer is also
predicted to occur at the magnetic equator by the model runs when the electron density hole formed. After the
significant F-layer uplift, the uplifted F-layer plasma diffuses downward along magnetic field lines to the adjacent
higher latitudes, resulting in electron density arches. Our results also suggest that the storm-generated
equatorward neutral winds can affect the latitudinal extent of the density arches as well as the formation of the
additional F-layer at low-latitudes. The model predicted results are also compared with satellite and radar
observations, showing good qualitative agreements.
DE: 2415 Equatorial ionosphere
DE: 2435 Ionospheric disturbances
DE: 2439 Ionospheric irregularities
DE: 2441 Ionospheric storms (7949)
DE: 2447 Modeling and forecasting
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting