Geomagnetic jerks and a high-resolution length-of-day profile for core studies

By subtracting computed atmospheric angular momentum from a time-series for length-of-day variations, we obtain a high-resolution time-series that is useful for studying the effects of the core on length-of-day variations. Features in this time-series are closely correlated with the time at which geomagnetic jerks have been observed, suggesting a role for the core in angular momentum exchange within the Earth system on timescales as short as one year, and that jerks are directly related to the processes responsible for changes in core angular momentum.