Journal cover Journal topic
Geoscientific Model Development An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 4.252 IF 4.252
  • IF 5-year value: 4.890 IF 5-year 4.890
  • CiteScore value: 4.49 CiteScore 4.49
  • SNIP value: 1.539 SNIP 1.539
  • SJR value: 2.404 SJR 2.404
  • IPP value: 4.28 IPP 4.28
  • h5-index value: 40 h5-index 40
  • Scimago H index value: 51 Scimago H index 51
Discussion papers
https://doi.org/10.5194/gmd-2018-237
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-2018-237
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Model description paper 11 Oct 2018

Model description paper | 11 Oct 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Geoscientific Model Development (GMD).

FVM 1.0: A nonhydrostatic finite-volume dynamical core formulation for IFS

Christian Kühnlein1, Willem Deconinck1, Rupert Klein2, Sylvie Malardel1,3, Zbigniew P. Piotrowski4, Piotr K. Smolarkiewicz1, Joanna Szmelter5, and Nils P. Wedi1 Christian Kühnlein et al.
  • 1European Centre for Medium-Range Weather Forecasts, Reading, UK
  • 2FB Mathematik und Informatik, Freie Universität Berlin, Berlin, Germany
  • 3Laboratoire de l'Atmosphére et des Cyclones, Météo-France, La Reunion, France
  • 4Institute of Meteorology and Water Management - National Research Institute, Warsaw, Poland
  • 5Loughborough University, UK

Abstract. We present a nonhydrostatic finite-volume global atmospheric model formulation for numerical weather prediction with the Integrated Forecasting System (IFS) at ECMWF, and compare it to the established operational spectral-transform formulation. The novel Finite-Volume Module of IFS (henceforth IFS-FVM) integrates the fully compressible equations using semi-implicit time stepping and non-oscillatory forward-in-time (NFT) Eulerian advection, whereas the spectral-transform IFS solves the hydrostatic primitive equations (optionally the fully compressible equations) using a semi-implicit semi-Lagrangian scheme. The IFS-FVM complements the spectral-transform counterpart by means of the finite-volume discretisation with a local communication footprint, fully conservative and monotone advective transport, all-scale deep-atmosphere fully compressible equations in a generalised height-based vertical coordinate, applicable on flexible meshes. Nevertheless, both the finite-volume and spectral-transform formulations can share the same quasi-uniform horizontal grid with co-located arrangement of variables, geospherical longitude-latitude coordinates, and physical parametrisations, thereby facilitating their comparison, coexistence and combination in IFS.

We highlight the advanced semi-implicit NFT finite-volume integration of the fully compressible equations of the novel IFS-FVM considering comprehensive moist-precipitating dynamics with coupling to the IFS cloud parametrisation by means of a generic interface. These developments – including a new horizontal-vertical split NFT MPDATA advective transport scheme, variable time stepping, effective preconditioning of the elliptic Helmholtz solver in the semi-implicit scheme, and a computationally efficient coding implementation – provide a basis for the efficacy of IFS-FVM and its application in global numerical weather prediction. Here, numerical experiments focus on relevant dry and moist-precipitating baroclinic instability at various resolutions. We show that the presented semi-implicit NFT finite-volume integration scheme on co-located meshes of IFS-FVM can provide highly competitive solution quality and computational performance to the proven semi-implicit semi-Lagrangian integration scheme of the spectral-transform IFS.

Christian Kühnlein et al.
Interactive discussion
Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Topical Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Christian Kühnlein et al.
Christian Kühnlein et al.
Viewed  
Total article views: 334 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
228 102 4 334 4 5
  • HTML: 228
  • PDF: 102
  • XML: 4
  • Total: 334
  • BibTeX: 4
  • EndNote: 5
Views and downloads (calculated since 11 Oct 2018)
Cumulative views and downloads (calculated since 11 Oct 2018)
Viewed (geographical distribution)  
Total article views: 333 (including HTML, PDF, and XML) Thereof 333 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 10 Dec 2018
Publications Copernicus
Download
Short summary
We present a novel finite-volume dynamical core formulation considered for future numerical weather prediction at ECMWF. We demonstrate that this formulation can be competitive in terms of solution quality and computational efficiency to the proven spectral-transform dynamical core formulation currently operational at ECMWF, while providing a local discretisation, conservative and monotone advective transport, and flexible meshes.
We present a novel finite-volume dynamical core formulation considered for future numerical...
Citation
Share