How does the external magnetic field influence the 1969 geomagnetic jerk detection?

Geomagnetic jerks are the most rapid phenomena of the core dynamics. Their study is important for the understanding of core dynamics and mantle conductivity. Although jerks have an internal origin, its detection in observatory and satellite data, is highly influenced by the external magnetic field contributions. In this paper we quantify the influence of the external field on geomagnetic jerks detection. We compare the 1969 jerk (X, Y and Z components) in two synthetic datasets, both from CM4 model (Sabaka et al., 2004): the first only core magnetic field and the second the core, including external and induced fields. Both are compared to real data from magnetic observatories.