In this paper we report the foF2 data measured at Korhogo station (Lat. 9.3° N; Long. 354.6° E; dip. 0.6° S) compared to predictions with IRI-2012 subroutine URSI and CCIR for different solar cycle phases (minimum, ascending, maximum, descending) and different geomagnetic activity classes (quiet, fluctuating, recurrent, shock). According to our investigations, predictions with IRI are in agreement with the measured data during daytime and show significant differences between them at night-time and especially before sunrise. Except at solar minimum, the gap between predictions and measured data are more appreciable during recurrent and shock conditions compared to quiet and fluctuating conditions. Our results also show that only URSI model expresses the signature of EXB drift phenomenon at solar maximum phase during the recurrent days and at ascending phase for fluctuating activity.

foF2 seasonal asymmetry is investigated at Korhogo station from 1992 to 2002. We show that equinoctial asymmetry is less pronounced and somwhere is absent trough out solar cycle phase. In general, the absence of equinoctial asymmetry may be due to the fact that in equinox and for each solar cycle phase, the asymmetry is due to Russell-McPherron mechanism. The solstice anomaly or annual anomaly is always observed throughout solar cycle phase. The minimum value of ΔfoF2 is inferior than −60% seen during all solar cycle phase at 0700 LT. This annual asymmetry may be due to interplanetary corpuscular radiation.

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This article examines magnetics clouds activity day's occurrence as a function of the different phases of the solar cycle and the duration of their geoeffectiveness. The study period extends from cycle 11 to cycle 24. Magnetic clouds activity day's occurrence were identified using pixel diagram from the years 1867 to 2019, that is to say, fourteen (14) solar cycles. The results show that in the study period: (1) there were 802 days of magnetic cloud activity with an effect lasting 1 day, 284 with an effect lasting 2 days and 141 having an effect three days; (2) the largest proportions of magnetic cloud activity days are recorded at maximum phase of the solar cycle, regardless of the type of magnetic cloud activity. These results also reveal that on average, there are 13 magnetic cloud activity days per year at the solar phase maximum.