The Hungarian magnetic network and the processing of the obtained data

In 1994-95 a geomagnetic survey was carried out on the territory of Hungary and the neighbouring regions on 195 stations. Magnetic declination, inclin ation and total field were directly observed. Some of the stations were mea sured jointly with Istituto Nazionale di Geofisica (ING), Roma. The results were reduced to the epoch of 1995.0. Normal fields for the magnetic compon ents were determined as second order functions of the geographic coordinate s. The polynomial coefficients have been computed in three different ways: by means of simple and weighted least squares procedure and using the adjus tment according to the "most frequent value". In the present paper the math ematical foundation of these methods and the comparison between the obtaine d results will be presented. (C) 1999 Elsevier Science Ltd. All rights rese rved.