SEASONAL EFFECT ON FOF2 VARIABILITY DURING ONE-DAY-SHOCK AT OUAGADOUGOU STATION DURING SOLAR CYCLES 20, 21 AND 22

The seasonal effect on the F2 sublayer critical frequency of ionosphere (foF2), during one-day-shock, at Ouagadougou station three solar cycles (20, 21, and 22) is examined in this work. It appears that summer has an tending to decrease values ​​of foF2 maximum, ascending descending phase. At cycle winter autumn do not modify amplitudes. minimum, decreases ​​in morning (08:00 a.m. 1:00 p.m.), while spring amplifies them (09:00 p.m.). In phase, winter, increase morning. ​​while increases them.