aIndustrial Physics Department, Ebonyi State University, Abakaliki, Nigeria e-mail: agbogodwina@yahoo.com
bDept. of Phy Sci. (Physics Unit), College of Nat. and App. Sci, Renaissance University, Ugbawka, Enugu State. e-mail: reachaustinbest@yahoo.com
cDepartment of Physics and Industrial Physics, Nnamdi Azikiwe University, Awka e-mail: as27ro@yahoo.com
1Corresponding author
Online published on 14 October, 2011.
Geomagnetic hourly recorded H-component field were obtained from geomagnetic website (World Data Center, Kyoto) for a set of six stations of nearly the same geographic longitude in a solar minimum year of 1996. The variability of the daily amplitudes of the H-component field was studied during quiet and disturbed days. The quiet and disturbed conditions in each station and on consecutive pair of days were found to be different. There were clear variations in both amplitude and phase. However, the amplitude of the day to day variability on disturbed consecutive pair of days were found to be greater than that on quiet conditions at all times. The variabilities were found to be due to magneto spheric and ionospheric currents. Since in the night time, ionospheric current is assumed to be absent, we suggest that the variation at nighttime is caused by distant magnetopheric current even on magnetically quiet days.
Geomagnetic field, quiet day, disturbed day, sequential variability, magneto spheric effect
