This paper focuses on the ionospheric anomalies observed in the F2 layer
at Tortosa in Ebre Observatory (40.8°N, 0.49°E), before and after a seismic
event in Morocco (Agadir). The data on optimal frequency of F2 layer (f0F2)
were acquired using ground based ionosonde. The median- based statistical
technique was applied to the data to examine the possible relationship between
the earthquake displacement field and the variation of the f0F2 in the
ionosphere. The results point to a variation characterized by absence of f0F2
values over four days before the earthquake and continue for almost three days
after the day of earthquake. The diurnal monthly median of the f0F2 values also
revealed anomalous which has been considered as supporting evidence for the observed
correlation.
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