Formulation of an ocean model for global climate simulations

S. M. Griffies (1) , A. Gnanadesikan (1) , K. W. Dixon (1) , J. P. Dunne (1) , R. Gerdes (2) , M. J. Harrison (1) , A. Rosati (1) , J. L. Russell (3) , B. L. Samuels (1) , M. J. Spelman (1) , M. Winton (1) , R. Zhang (3)

1 GFDL - NOAA Geophysical Fluid Dynamics Laboratory
2 AWI - Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung = Alfred Wegener Institute for Polar and Marine Research = Institut Alfred-Wegener pour la recherche polaire et marine
3 AOS Program - Atmospheric and Oceanic Sciences Program [Princeton]

This paper summarizes the formulation of the ocean component to the Geophysical Fluid Dynamics Laboratory's (GFDL) coupled climate model used for the 4th IPCC Assessment (AR4) of global climate change. In particular, it reviews elements of ocean climate models and how they are pieced together for use in a state-of-the-art coupled model. Novel issues are also highlighted, with particular attention given to sensitivity of the coupled simulation to physical parameterizations and numerical methods. Features of the model described here include the following: (1) tripolar grid to resolve the Arctic Ocean without polar filtering, (2) partial bottom step representation of topography to better represent topographically influenced advective and wave processes, (3) more accurate equation of state, (4) three-dimensional flux limited tracer advection to reduce overshoots and undershoots, (5) incorporation of regional climatological variability in shortwave penetration, (6) neutral physics parameterization for representation of the pathways of tracer transport, (7) staggered time stepping for tracer conservation and numerical efficiency, (8) anisotropic horizontal viscosities for representation of equatorial currents, (9) parameterization of exchange with marginal seas, (10) incorporation of a free surface that accomodates a dynamic ice model and wave propagation, (11) transport of water across the ocean free surface to eliminate unphysical "virtual tracer flux" methods, (12) parameterization of tidal mixing on continental shelves.

Domaines: Océan, Atmosphère

S. M. Griffies, A. Gnanadesikan, K. W. Dixon, J. P. Dunne, R. Gerdes, et al.. Formulation of an ocean model for global climate simulations. Ocean Science Discussions, 2005, 2 (3), pp.165-246. ⟨hal-00298422⟩