Using Locally Generated Magnetic Indices to Characterize the Ionosphere From Magnetic Data Acquisition System (Magdas) Ground Based Observatories in Nigeria.

Abstract

This work presents an attempt to establish a baseline for geomagnetic indices inNigeria. This is particularly very crucial since these indices give indications of theseverity of magnetic fluctuations, and hence the level of disturbances in theionosphere. K (an index which measures the magnetic perturbations of theplanetary field) and A (a linear measure of the Earth's field that provides a dailyaverage level for geomagnetic activity) geomagnetic indices were generated locallyfrom geomagnetic data obtained using ground based MAGDAS magnetometerslocated at Abuja (9 ̊ 40’N, 7 ̊ 29’E), Ilorin (8 ̊30’N, 4 ̊33’E) and Lagos (6 ̊27’N,3 ̊23’E) in Nigeria using Computer-based derivation. The indices generated wereused to characterize the ionosphere over the Magdas magnetometer Nigerianetwork stations. Results obtained showed average K values of 3.5 (ABU), 4.60(LAG) and 4.13 (ILR), the ionosphere over the three stations was found to berelatively active (4.08) thus setting the baseline for characterizing the ionosphereover Nigeria from ground based magnetometers.