Acknowledgement
This work was done at the Department of Physics, CNCS, Institute of Geophysics Space Science and Astronomy, Addis Ababa University, Ethiopia. The authors are thankful to them. We thankful and gratefully acknowledge the following data sources and their staffs for the opportunity to access the ground magnetometer data. The datasets generated during and/or analysed during this study are available in the following links. The data for this study were downloaded from Low-latitude Ionospheric Sensor Network LISN (http://lisn.igp.gob.pe/data/) for PIU & LET stations, from the INTERMAGNET data center (https://www.intermagnet. org/index-eng.php) for AAE, HUA, KOU, TAM, ABG, KDA & GUA stations, from AMBER Network (http://magnetometers. bc.edu/index.php/amber2) for ETH station, from the Bureau Centralde Magntisme Terrestre BCMT Network (http://www.bcmt.fr/wamnetnetwork.html) for the SAM station, from WDC Catalogue [the World Data Centre (WDC) for Geomagnetism, Edinburgh (http://www.wdc.bgs.ac.uk/dataportal/)]. TTB & QGZ station, and from SuperMAG website (http://supermag.jhuapl.edu/) for TIR, BCL, LKW & KTB stations. The 1 min-averaged data Solar Index F10.7 and R Sunspot Number (new version) data as well as the, Kp*10Kp*10 Index are obtained from the OMNIWeb Data Explorer (https://omniweb.gsfc.nasa.gov/form/dx1.html).
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