Impact of partial steps and momentum advection schemes in a global ocean circulation model at eddy-permitting resolution - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Ocean Dynamics Année : 2006

Impact of partial steps and momentum advection schemes in a global ocean circulation model at eddy-permitting resolution

Anne-Marie Tréguier
  • Fonction : Auteur
  • PersonId : 848260
Corine Derval
  • Fonction : Auteur
Edmée Durand
  • Fonction : Auteur
Elisabeth Rémy
  • Fonction : Auteur
  • PersonId : 1164834

Résumé

Series of sensitivity tests were performed with a z-coordinate, global eddy-permitting (1/4°) ocean/sea-ice model (the ORCA-R025 model configuration developed for the DRAKKAR project) to carefully evaluate the impact of recent state-of-the-art numerical schemes on model solutions. The combination of an energy–enstrophy conserving (EEN) scheme for momentum advection with a partial step (PS) representation of the bottom topography yields significant improvements in the mean circulation. Well known biases in the representation of western boundary currents, such as in the Atlantic the detachment of the Gulf Stream, the path of the North Atlantic Current, the location of the Confluence, and the strength of the Zapiola Eddy in the south Atlantic, are partly corrected. Similar improvements are found in the Pacific, Indian, and Southern Oceans, and characteristics of the mean flow are generally much closer to observations. Comparisons with other state-of-the-art models show that the ORCA-R025 configuration generally performs better at similar resolution. In addition, the model solution is often comparable to solutions obtained at 1/6 or 1/10° resolution in some aspects concerning mean flow patterns and distribution of eddy kinetic energy. Although the reasons for these improvements are not analyzed in detail in this paper, evidence is shown that the combination of EEN with PS reduces numerical noise near the bottom, which is likely to affect current–topography interactions in a systematic way. We conclude that significant corrections of the mean biases presently seen in general circulation model solutions at eddy-permitting resolution can still be expected from the development of numerical methods, which represent an alternative to increasing resolution.

Dates et versions

hal-00138383 , version 1 (26-03-2007)

Identifiants

Citer

Bernard Barnier, Gurvan Madec, Thierry Penduff, Jean-Marc Molines, Anne-Marie Tréguier, et al.. Impact of partial steps and momentum advection schemes in a global ocean circulation model at eddy-permitting resolution. Ocean Dynamics, 2006, 56 (5-6), pp.543-567. ⟨10.1007/s10236-006-0082-1⟩. ⟨hal-00138383⟩
487 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More