[PEM12-P25] Characterization of counter electrojet current according to specific time frame in Southeast Asian sector
Counter electrojet, CEJ current refers to the sudden reversal of equatorial electrojet, EEJ current towards the opposite direction (westward) that is usually happen at dip-equatorial region. In this study, the CEJ occurrence at Southeast Asia region is identified using EUEL index during solar cycle 24. The EUEL index is selected as it is a local index that define EEJ at particular location without global magnetospheric disturbance. The CEJ current can be categorized into a few types depending on its occurrence: morning CEJ (0500-1100), afternoon CEJ (1300-1700), evening CEJ (1800-2200) and night CEJ (2300-0400). The continuous 1-minute data has been utilized to describe CEJ behaviour in each time frame. This behaviour is including the amplitude and duration of the current itself, as well as its dependence toward local time and seasons.