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Grüne et al. investigate fluid motions in the Earth’s outer core, which generate the geomagnetic field. Using 1997–2023 data from satellites (Ørsted, CHAMP, CryoSat‑2, Swarm) and ground observatories, they construct a long-term secular variation (SV) dataset to study core dynamics. “The energies within both the toroidal and poloidal flow components converge rapidly as a function of spherical harmonic degree, as enforced by the chosen spatial norm. We note here that the flow is predominantly toroidal. Most of the toroidal energy is in spherical harmonic degree 1 – associated with westward drift – until 2010, where spherical harmonic degree 2 becomes dominant. Around the same time, in the poloidal flow energy, we see an increase in spherical harmonic degree 3, which continues until 2023. These changes indicate a re-distribution of energy in the large-scale flow over the past 20 years… A strong westward drift underneath the Atlantic hemisphere at low latitudes turns into poleward flow beneath North America. Underneath the Bering Strait, it concentrates into the high-amplitude jet along the tangent cylinder. Under East Asia, it flows south towards the equator again, where it re-organises into the Atlantic westward flow band.” The authors also note “...concentrated eastward drift underneath the equatorial Pacific after 2011.” These observations reveal distinct asymmetries and convergences in the core flow. “We see that there is an up- and downwelling pattern associated with the high latitude jet underneath the Bering Strait, which is not mirrored in the southern hemisphere. There is also a region of strong flow convergence underneath the western equatorial Pacific, where the equatorial Atlantic westward flow meets the equatorial Pacific eastward flow. Eastward flow beneath the low-latitude Pacific is sourced from an upwelling beneath Indonesia and downwelling underneath Central America… In addition to this large-scale, steady pattern, some more rapid flow changes occur.” On shorter timescales, the flow shows evolving regional features. “Over the period between 2001 and 2004, a counter-clockwise eddy forms beneath the South Indian Ocean, then disappears again in 2011–2012, as a result of its western half stretching out to the west. Under the Pacific hemisphere, 2010, marks the beginning of a period of increased dynamics in this region. Most notably, between 2010 and 2014, a low-latitude patch of flow between about 160°E and 180°E changes direction from westwards to eastwards, and remains stably eastwards after, which is associated with the concentration of the upwelling region at these longitudes.” Focusing on the azimuthal component, the authors identify regions of rapid acceleration. Localized pulses reach up to twice the background amplitude and appear primarily at mid-to-low latitudes, often beneath the Indian Ocean, the Atlantic, or, especially after 2010, the west Pacific. “The section spanning the region between about 120°E to 240°E (corresponding approximately to the Pacific region), has areas of very high acceleration amplitudes. Alternating negative and positive acceleration features form patterns of sloping stripes, interpreted as eastward propagation of high-amplitude spots in a region around 120°E (tentatively, since the pattern only appears over a narrow band of longitude), and, with larger amplitude, westward movement east of 150°E. The former only appears around 2015, the latter becomes well defined around 2010 and remains throughout the rest of the interval studied. Fitting a straight line to the slope of the westward propagating features yields an approximate propagation velocity of 1700 km/yr, significantly faster than the typical fluid flow velocities.”