Spatial and temporal distribution of ionospheric currents-4: altitude – local time and altitude – longitude cross sections of Equatoriall Electrojet current density

Abstract

The rare opportunity given by the unprecedented spatial and temporal coverage of POGO satellites data is exploited to present all possible cross sections of equatorial electrojet (EEJ) current in the group of papers. Here the all-longitude means at 7 hours centred on local noon and the daytime means at 36 longitudes, of the vertical distribution parameters of EEJ current density are provided. The altitude–local time cross section of EEJ current density has one contour cell peaking at (12 h, 106 km) while the altitude-longitude cross section of EEJ current density has three contour cells peaking at (1000E, 106 km), (1900E, 106 km) and (2900E, 106 km). In both cross sections the contour of a given current density extends farther from the altitude of peak current density when the peak current density at the centre of EEJ is larger. This accounts for the wavy nature of the altitude-longitude cross section. Attention is drawn to two rocket measurements that support this phenomenon. The following conclusions are also reached. (a) The continuous distribution of current density model reproduces the altitude distribution parameters of EEJ current density very well, (b) the altitude distribution parameters of EEJ current density in India and Peru are not significantly different and (c) The altitude distribution parameters of EEJ current density from rockets data and from POGO Satellites data are not significantly different and that (d) It is essential to take into account the lack of symmetry between the vertical distributions of EEJ current density below and above the altitude of EEJ peak current density. (Global Journal of Pure and Applied Sciences: 2002 8(3): 389-398)