Time‐independent and time‐dependent behaviour of high‐latitude flux bundles at the core‐mantle boundary

[1] Using a numerical dynamo model, we examine whether quasi-stationary high latitude flux bundles which are observed in the geomagnetic field over the last 300 years, and possibly over much longer time periods, result from thermal core-mantle interactions. We do so by imposing lateral heat flux variations at the core-mantle boundary based upon the dominant pattern of seismic heterogeneity in the lowermost mantle. We find that the time-averaged field then has a similar arrangement of flux bundles to that observed during the last few hundred years. However, the field is time-dependent, and this arrangement of flux bundles is not a feature of the field at all times.

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