Geomagnetic disturbance during quiet period at low-latitude stations

Abstract

A sudden impulse due to unexpected Coronal Mass Ejection (CME) has been detected by ACE spacecraft on 23rd December 2014 resulting the northward interplanetary magnetic field, IMF Bz and sudden enhancement on Solar Wind speed (V sw) and Solar Wind dynamic pressure (SW Pdyn). This shock passage also gives response to the ground-based magnetometer and geomagnetic variations of H-component which extracted from INTERMAGNET. The significant variations are observed at high latitude station; HRN and low latitude stations; GUA, AAE, MBO and KOU, based on INTERMAGNET latitude classification. The comparison of H-component between these two latitudinal stations; high latitude (HL) and low latitude (LL) has been studied in order to explain the effect of this event to our Earth's magnetic field. We also studied dayside and night side effect at different stations. In general cases during southward IMF Bz, H-component variations at HL detected larger compared to LL. However, for this event, due to northward IMF Bz, H-component variations observed differently from its regular pattern. The results reveal that H-component variations of the stations at low latitude during day time show the higher variation compared to the stations at low latitude during night time or at high latitude. Details of the analysis will be discussed throughout this paper.