We present investigations of rapidly rotating convection in a thick spherical shell geometry relevant to planetary cores, comparing results from quasigeostrophic (QG), 3D and hybrid QG3D models. The 170 reported calculations span Ekman numbers, Ek, between 10−4 and 10−10, Rayleigh numbers, Ra, between 2 and 150 times supercritical and Prandtl numbers, Pr, between 10 and 10−2. The default boundary conditions are noslip at both the ICB and the CMB for the velocity field, with fixed temperatures at the ICB and the CMB. Cases driven by both homogeneous and inhomogeneous CMB heat flux patterns are also explored, the latter including lateral variations, as measured by Q*, the peaktopeak amplitude of the pattern divided by its mean, taking values up to 5. The QG model is based on the opensource pizza code. We extend this in a hybrid approach to include the temperature field on a 3D grid. In general, we find convection is dominated by zonal jets at middepths in the shell, with thermal Rossby waves prominent close to the outer boundary when the driving is weaker. For the thick spherical shell geometry studied here the hybrid method is best suited for studying convection at modest forcing, $Ra \le 10 \, more »
 Publication Date:
 NSFPAR ID:
 10368042
 Journal Name:
 Geophysical Journal International
 Volume:
 231
 Issue:
 1
 Page Range or eLocationID:
 p. 129158
 ISSN:
 0956540X
 Publisher:
 Oxford University Press
 Sponsoring Org:
 National Science Foundation
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