Relocating Port Stanley Observatory

Port Stanley Observatory (PST) is one of the nine geomagnetic observatories maintained and operated by the British Geological Survey (BGS). It is located on Sapper Hill to the west of Port Stanley, Falkland Islands. The observatory has been operational since February 1994 and contributes to the global INTERMAGNET network of geomagnetic observatories. PST has been providing continuous long-term monitoring in the region of the South Atlantic Anomaly (SAA) for over 30 years. In March 2017 an antenna was installed on a communications tower sharing the hill with the observatory, with the resulting RF interference leading to a significant deterioration in data quality. Engineering and data processing efforts to eliminate the RF interference were unsuccessful and in 2020 a decision was taken to relocate the observatory to a new site, 3.5 km to the east. The new observatory installation was completed during 2023/4 with data available from June 2024. Prior to decommissioning PST, both observatories will be run in parallel for a period of two years with the aim of establishing whether the new site could be considered a continuation of the PST time series. In this paper we describe the work undertaken to establish the new observatory. We also present some initial data comparisons between the two sites.