Progress Toward A Regional Geomagnetic Field Model Embracing The Sq Variation

Global and regional geomagnetic field models give the components of the<br>geomagnetic field as functions of position and epoch. However, the only<br>temporal variation generally catered for in these models is the secular variation.<br>There is an increasing need amongst certain users for models able to provide<br>shorter term temporal variations, such as the solar quiet day (Sq) variation. In this<br>paper we give a brief review of the Sq variation and describe how artificial neural<br>networks (ANNs) are being used to develop a geomagnetic daily variation model<br>for the Southern African region.