Abstract:
The F2-region response to the storm of January 28, 1985, was investigated in this research using
some ionospheric stations from East Asian and Euro-African sectors. The sectors were chosen
because of their huge time difference, which enabled the proper identification of whether or not
plasma is redistributed owing to sunrise effect when a storm occurs. The storm occurred around
14:00 universal time (UT), which corresponded with local time (LT) of Euro-African sector of
between 1-4 p.m. and 10-11 p.m. of East Asian sector. From the result obtained, it was concluded
that sunrise effect could redistribute the plasma when a geomagnetic storm occurs due to the fact
that the three low latitude stations in Euro-African behaved in an undefined manner, while the
response of the East Asian stations agreed with existing theories
