Resolution No.15 (1973): Geomagnetic observation in the southern hemisphere

IAGA, considering the need for better models of variations of the geomagnetic field (in particular, secular changes, disturbances, and longitudinal changes in Sq and L) and recognising the dependence of such models on a suitable geographical distribution of the data, urges that every effort be made to improve the distribution and density of observatories in the southern hemisphere.