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Description: A stably stratified layer at the top of Earth's liquid core has been independently inferred from seismology, geomagnetism, and geodynamics, contradicting the classic view of a thermally and chemically well-mixed core. Such a layer would have significant implications for the dynamics and evolution of the core and the power available to generate the geomagnetic field. Previous models have attempted to explain observations of anomalously slow seismic wave speeds, that may extend up to ~350 km below the core-mantle boundary (CMB), with a global stably stratified layer resulting from diffusive processes. However, geomagnetic features such as high-latitude flux patches and reversed flux in the Atlantic are often associated with radial flow near the CMB and thus appear incompatible with a thick global stable layer. Here we propose that both geomagnetic and seismic observations can be reconciled within a framework of regional thermal inversion at the top of the core due to imposed lateral variations in CMB heat flow. These regional thermal inversion layers are expected under anomalously hot regions of the lowermost mantle, can extend 100's of kilometres into the core and, if sufficiently large and strong, can result in a 1D temperature profile that could be mistaken for the existence of a density stratified global layer below the CMB. However, dynamic links between regions of thermal inversion and active convection result in radial motion everywhere within the core, thereby avoiding any conflict with geomagnetic observations associated with such motions.