Numerical modeling of the equatorial electrojet UT-variation on the basis of the model GSM TIP
Open Access
- 13 June 2007
- journal article
- Published by Copernicus GmbH in Advances in Radio Science
- Vol. 5 (GHJ), 385-392
- https://doi.org/10.5194/ars-5-385-2007
Abstract
In the presented work the results of numerical modeling of the UT-variation of the equatorial electrojet, executed on the basis of the model GSM TIP are presented, taking into account the dynamo electric fields generated by thermospheric winds in a current-carrying layer of the ionosphere at heights 80–175 km above a surface of the Earth. To the Global Self-consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP), developed in WD IZMIRAN, a new block for the calculation of electric fields in the ionosphere has been added. In this block the solution of the three-dimensional equation describing the conservation law of the full current in the Earth's ionosphere is reduced to the solution of the two-dimensional equation by integration along geomagnetic field lines. Calculations of parameters of the near-Earth space plasmas have been executed for quiet equinoctial conditions on 22 March 1987 during the minimum of solar activity. It has been shown, that there is a distinct semidiurnal harmonic in the diurnal behavior of the linear density of the equatorial electrojet with maxima at 23:00 UT and 15:00 UT, as well as with minima at 06:00 UT and 20:00 UT. The greatest and smallest values of the peak intensity of the equatorial electrojet with respect to the diurnal behavior can differ by a factor of two. The longitudinal extent of the area of the equatorial electrojet does hardly show any UT-variation, but the greatest longitudinal extent is at 06 UT. With the growth of the peak intensity of the equatorial electrojet its latitudinal extent also increases (on ~5–10°) a little. At the same time the equatorial electrojet in the maxima of intensity has approximately an identical width, whereas in the minima the electrojet is narrow in the morning and wide in the afternoon. As for the surface density of the equatorial electrojet, its UT-variation is much weaker and equals ~1–3 A/km2 and the peak intensity is equal ~15–20 A/km2. The latitudinal extent of the surface density of the equatorial electrojet is maximal at 23:00 UT and 15:00 UT and minimal at 06:00 UT and 20:00 UT.This publication has 20 references indexed in Scilit:
- Numerical simulation of the electric field and zonal current in the Earth’s ionosphere: The dynamo field and equatorial electrojetGeomagnetism and Aeronomy, 2006
- The field of the equatorial electrojet from CHAMP dataAnnales Geophysicae, 2006
- Electrodynamics in the low and middle latitude ionosphere: a tutorialJournal of Atmospheric and Solar-Terrestrial Physics, 2004
- Equatorial electrojet from Ørsted scalar magnetic field observationsJournal of Geophysical Research, 2003
- Calculated and observed ionospheric parameters for a Magion 2 passage and EISCAT data on July 31, 1990Journal of Geophysical Research, 1998
- Electric fields in the Earth's magnetosphere and ionosphereSpace Science Reviews, 1976
- Electric currents in the ionosphere - The conductivityPhilosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1953
- The equatorial electrojet as detected from the abnormal electric current distribution above Huancayo, Peru, and elsewhereArchiv für Meteorologie, Geophysik und Bioklimatologie Serie A, 1951
- The magnetic diurnal variation of the horizontal force near the magnetic equatorTerrestrial Magnetism and Atmospheric Electricity, 1947
- The Magnetic Field of SunspotsMonthly Notices of the Royal Astronomical Society, 1933