New K-Indices from South Atlantic Observatories : Port Stanley and Ascension Island

Port Stanley and Ascension Island magnetic observatories have been in continuous operation since the early 1990's. These remote South Atlantic locations provide much needed coverage in the global network of geomagnetic observatories and help to monitor the South Atlantic Anomaly. To enhance the production of longitude-sector planetary magnetic activity indices there is a requirement for local 3-hourly K-index values from Port Stanley (PST) observatory. We describe the process followed to establish an automated routine for the derivation of the indices and we assess the congruence of the indices to those available from other suitably located observatories. A similar procedure has been followed for Ascension Island observatory although this is not shown here.