An operational geomagnetic baseline derivation for ground magnetometer data located in mid-latitudinal regions

As a direct response to the increasing dependency on technological systems, the need for operational now- and forecasting of space weather events has been rising within the past decades.

In order to monitor these events and their impacts, ground magnetic field data has proven to be a long-lasting and powerful source of information. Especially for the determination of the intensity and strength of solar forcing events, the derivation of geomagnetic baselines that extract the solar forcing portion from the rest of the superposing sources within geomagnetic field signals are of importance.

In this work, we present a derivation method for determining the geomagnetic baseline for magnetic field data recorded at mid-latitudes. The contributing sources include the secular variation and the day-to-day variability, enabling the extraction of solar forcing contributions accurately. The derivation method is based on standard algorithms and does not need a-priori information other than the geomagnetic field measurements themselves. This enables the production of the baseline in near-real time and is thus suitable for operational purposes.

The deployment of the introduced baseline allows for the operational identification of solar forcing intensities and may also be used for derivation of magnetic indices that use magnetic field data from mid-latitudinal observatories.