HR: 12:10h
AN: A52B-09    [Abstracts]
TI: Main Ionospheric Trough and Equatorial Ionization Anomaly During Substorms With the Different UT Onset Moments
AU: * Klimenko, M V
EM: maksim.klimenko@mail.ru
AF: Kaliningrad State Technical University, Sovetsky Av., 1, Kaliningrad, 236000, Russian Federation
AU: Klimenko, V V
EM: pcizmiran@gazinter.net
AF: West Department of IZMIRAN, Pobedy Av., 41, Kaliningrad, 236017, Russian Federation
AU: Bryukhanov, V V
EM: bryukhanov@klgtu.ru
AF: Kaliningrad State Technical University, Sovetsky Av., 1, Kaliningrad, 236000, Russian Federation
AB: In the given work the numerical calculation results of ionospheric effects of four modeling substorms which have begun in 00, 06, 12 and 18 UT are presented. Calculations are executed on the basis of Global Self-consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP), developed in WD IZMIRAN, added by the new block of calculation of electric fields in the ionosphere of the Earth for vernal equinox conditions in the minimum of solar activity. In calculations we considered superposition of magnetospheric convection electric field (at set potential differences through polar caps and field aligned currents of the second zone with taking into account of particle precipitation) and dynamo field generated by thermospheric winds without taking into account the tides. It is shown, that in the given statement of problem the substorms cause strong positive disturbances in F-region of ionosphere in night sector. Negative disturbances are much less and arise, mainly, at night in the middle and low latitudes. During substorms longitudinal extent of main ionospheric trough increases. The substorm beginning in 18 UT, causes negative disturbances in high latitudes except for a southern polar cap. Besides there is "stratification" of the main ionospheric trough. As a result in southern hemisphere the additional high-latitude trough which is absent in quiet conditions is formed. "Stratification" of the main ionospheric trough occurs in northern hemisphere at 6 hours after the beginning of the substorm. These "stratifications" are consequence non-stationary magnetospheric convection. Distinction between these events consists that "stratification" in a southern hemisphere occurs in active phase of substorm, and in northern hemisphere in recovery phase. During a substorm beginning in 00 UT, foF2 increases in all northern polar cap. Positive disturbances of foF2 in the equatorial anomaly region cause all presented substorms, except for a substorm beginning in 18 UT. This substorm causes small negative disturbances in the equatorial anomaly region in the Indian longitudinal sector.
DE: 2407 Auroral ionosphere (2704)
DE: 2411 Electric fields (2712)
DE: 2415 Equatorial ionosphere
DE: 2447 Modeling and forecasting
DE: 2790 Substorms
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly