%0 Journal Article %T Core field acceleration pulse as a common cause of the 2003and 2007 geomagnetic jerks %+ Institut de Physique du Globe de Paris (IPGP) %A Chulliat, A. %A Thébault, Erwan %A Hulot, Gauthier %< avec comité de lecture %@ 0094-8276 %J Geophysical Research Letters %I American Geophysical Union %V 37 %N 7 %P L07301 %8 2010 %D 2010 %R 10.1029/2009GL042019 %Z Sciences of the Universe [physics]Journal articles %X Using observatory data, we report the detection of ageomagnetic jerk in 2007, which we relate to a jump inthe second derivative of the geomagnetic field previouslynoted in satellite data. Although not of worldwide extent,this jerk is very intense in the South Atlantic region.Using the CHAOS‐2 model, we show that both this jerkand the previous 2003 jerk are caused by a single corefield acceleration pulse reaching its maximum power near2006.0. This pulse seems to be simultaneously occurringin several regions of the core surface where it correspondsto dominant n = 5 and 6 spherical harmonic modes.Geometrical attenuation explains why the 2003 and 2007jerks are local and not fully synchronized at the Earth’ssurface. Our results suggest that this core field accelerationpulse is the relevant phenomenon to be investigated fromthe point of view of core dynamics, rather than the jerksthemselves. Citation: Chulliat, A., E. Thébault, and G. Hulot(2010), Core field acceleration pulse as a common cause of the2003 and 2007 geomagnetic jerks %G English %2 https://insu.hal.science/insu-01285705/document %2 https://insu.hal.science/insu-01285705/file/grl2019.pdf %L insu-01285705 %U https://insu.hal.science/insu-01285705 %~ INSU %~ UNIV-PARIS7 %~ AFRIQ %~ CNRS %~ IPGP %~ SORBONNE-UNIVERSITE %~ UNIV-PARIS %~ SU-TI %~ ALLIANCE-SU