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Detailed exploration of forward-in-time differencing on a sphere, edge-based discretisation techniques, and a geospherical framework. Includes shallow water models, zonal orographic flow, rotating stratified fluids, and more. Research emphasizes unstructured mesh-based schemes for atmospheric flows. Plans for future work include generalizing non-hydrostatic edge-based models to global applications.
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Forward-in-time differencing on a sphere: an edge based discretisation Joanna Szmelter and Piotr K Smolarkiewicz Loughborough University, UK NCAR, Boulder, Colorado Wu J, Zhu J.Z, Szmelter J, Zienkiewicz O.C, Computational Mechanics, 1990. Szmelter J, Marchant M.J, Evans A., Weatherill N.P ,Comp. Meth. Appl. Mech. Eng., 1992
Geospherical framework NFT MPDATA: a general template (Szmelter & Smolarkiewicz, J. Comput. Phys. 2010)
The edge-based discretisation Edges Median dual mesh --- Finite volumes (MPDATA Smolarkiewicz & Szmelter , J. Comput. Phys. 2005)
A shallow water model Zonal orographic flow (Grose&Hoskins; Williamson)
Rossby-Haurwitz Wave 5 days 14 days
A global hydrostatic model isentropic, isosteric/ isopycnic Rotating stratified fluid An Eulerian-Lagrangian form Isentropic model
A stratified 3D mesoscale flow past an isolated hill Reduced planets (Wedi & Smolarkiewicz, QJR 2009)
Global stratified flow past An isolated hill (Smolarkiewicz & Rotunno, J. Atmos. Sci. 1989) (Hunt & Snyder J. Fluid Mech. 1980) 4 hours Fr=2 Fr=1 Fr=0.5
(Smith, Advances in Geophys 1979) (Hunt, Olafsson & Bougeault, QJR 2001)
REMARKS Presented work provides means for study and developments of unstructured mesh based schemes for atmospheric flows. Future work: Generalisation of non-hydrostatic edge-based limited area models to global models