South Georgia Magnetic Observatory

The British Geological Survey (BGS) operates seven geomagnetic observatories, four of which are overseas. Prior to the 1982 Falklands conflict, a magnetic observatory at King Edward Point, South Georgia was operated by the British Antarctic Survey (BAS). During the occupation of South Georgia, the observatory suffered heavy damage and was subsequently abandoned. In 2008, BGS took the decision to re-establish a magnetic observatory on South Georgia in collaboration with BAS. One of the main functions of the new observatory is to provide data for global models of the Earth’s magnetic field. An improved spatial distribution of geomagnetic observatories is a goal to improve the quality of these models and mid-ocean islands are therefore important observing locations to help achieve this. South Georgia is also particularly interesting because it sits over a rapidly weakening feature in the Earth’s field, known as the South Atlantic Anomaly. The new observatory installation was planned over two phases. Phase one in early 2010, saw the installation of the observatory infrastructure, including the fluxgate and proton housings. Plans for phase 2, in early 2011 are the completion of the Absolute House, the installation of cabling, instruments and communications. Details of the installation work in both phases, the instruments and the current operations will be described. The first magnetic measurements on South Georgia for nearly 30 years will be presented and the data quality discussed.