A global network of geomagnetic observatories is the backbone of studies concerning the field sources in the Earth's core, ionosphere and magnetosphere. Moreover, the data are used for models and maps with practical applications, and the determination of magnetic activity indices for space weather monitoring.

The South African Geodynamic Observatory Sutherland (SAGOS) of GFZ was established during the years 1998 – 2000 based on an Agreement on Cooperative Activities between the National Research Foundation (NRF) and GFZ, signed in August 1998. SAGOS is located at the site of the South African Astronomical Observatory (SAAO). The operation and maintenance of the SAGOS instrumentation is jointly done by staff of SAAO and GFZ.

The GEOFON program consists of a seismic network (GE Network) with global coverage, a seismological data centre (GEOFON DC) and a global seismic monitoring system (GEOFON EQinfo). These three pillars are part of the MESI research infrastructure of the Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences. aiming at facilitating research in seismology. GEOFON provides real-time seismic data, access to its own and third party data from our archive facilities as well as global and rapid earthquake information. The GEOFON seismological software development effort can be considered the fourth module of the GEOFON Program. Among the software we provide to the community is the SeisComP3 package that we use for all our operations. Data, services, products and software openly distributed by GEOFON are used daily by hundreds of users and data centres worldwide.

Additional information is at the GEOFON web page, http://geofon.gfz-potsdam.de/

Contact: geofon@gfz-potsdam.de

Since the early 1990s, the GFZ has operated a global GNSS station network with currently about 70 stations for precise satellite clock & orbit determination, realization of the terrestrial reference frame, radio occultation measurements or studies on crust dynamics.