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arXiv · 2402.13738

A mixed finite-element, finite-volume, semi-implicit discretisation for atmospheric dynamics: Spherical geometry

Thomas Melvin·Ben Shipway·Nigel Wood·Tommaso Benacchio·Thomas Bendall·Ian Boutle·Alex Brown·Christine Johnson·James Kent·Stephen Pring·Chris Smith·Mohamed Zerroukat·Colin Cotter·John Thuburn
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Abstract

The reformulation of the Met Office's dynamical core for weather and climate prediction previously described by the authors is extended to spherical domains using a cubed-sphere mesh. This paper updates the semi-implicit mixed finite-element formulation to be suitable for spherical domains. In particular the finite-volume transport scheme is extended to take account of non-uniform, non-orthogonal meshes and uses an advective-then-flux formulation so that increment from the transport scheme is linear in the divergence. The resulting model is then applied to a standard set of dry dynamical core tests and compared to the existing semi-implicit semi-Lagrangian dynamical core currently used in the Met Office's operational model.

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Thomas Melvin, Ben Shipway, Nigel Wood, Tommaso Benacchio, Thomas Bendall, Ian Boutle, Alex Brown, Christine Johnson, James Kent, Stephen Pring, Chris Smith, Mohamed Zerroukat, Colin Cotter, John Thuburn. 2024-02-21. A mixed finite-element, finite-volume, semi-implicit discretisation for atmospheric dynamics: Spherical geometry. https://arxiv.org/abs/2402.13738

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