Evaluation of ocean model ventilation with CFC-11: comparison of 13 global ocean models

Dutay, J.-C., J.L. Bullister, S.C. Doney, J.C. Orr, R. Najjar, K. Caldeira, J.-M. Campin, H. Drange, M. Follows, Y. Gao, N. Gruber, M.W. Hecht, A. Ishida, F. Joos, K. Lindsay, G. Madec, E. Maier-Reimer, J.C. Marshall, R.J. Matear, P. Monfray, G.-K. Plattner, J. Sarmiento, R. Schlitzer, R. Slater, I.J. Totterdell, M.-F. Weirig, Y. Yamanaka, and A. Yool, Ocean Modelling, 4(2), 89-120, 2002.

Jean-Claude Dutay, James C. Orr, and Patrick Monfray, Laboratoire des Sciences du Climat et de l'Environnement, Unite Mixte de Recherche CEA-CNRS, Gif-sur-Yvette, France

John L. Bullister, Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, Washington, USA

Scott C. Doney, Keith Lindsay, and Matthew W. Hecht, National Center for Atmospheric Research, Boulder, Colorado, USA

Ray Najjar, Department of Meteorology, Pennsylvania State University, University Park, Pennsylvania, USA

Ken Caldeira, Lawrence Livermore National Laboratory, Livermore, California, USA

Jean-Michel Campin, Laboratory for Planetary and Atmospheric Physics, University of Liege, Belgium

Helge Drange and Yongqi Gao, Nansen Enviromental and Remote Sensing Center, Bergen, Norway

Mick Follows and John C. Marshall, Program in Atmospheres, Oceans and Climate, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA

Nicolas Gruber, Jorge Sarmiento, and Rick Slater, Program in Atmospheric and Oceanic Sciences, Princeton University, Princeton, New Jersey, USA

Akio Ishida and Yasuhiro Yamanaka, Institute for Global Change Research, Tokyo, Japan

Fortunat Joos and Gian-Kasper Plattner, Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland

Gurvan Madec, Laboratoire d'Oceanographie Dynamique et de Climatologie, Paris, France

Ernst Maier-Reimer, Max Planck Institut für Meteorologie, Hamburg, Germany

Richard J. Matear, CSIRO Division of Marine Research, Hobart, Tasmania, Australia

Reiner Schlitzer and Marie-France Weirig, Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany

Ian J. Totterdell and Andrew Yool, Southampton Oceanography Centre, Southampton, UK


We compared the 13 models participating in the Ocean Carbon Model Intercomparaison Project (OCMIP) with regards to their skill in matching observed distributions of CFC-11. This analysis charactarize the abilities of these models to ventilate the ocean on time scales relevant for anthropogenic CO2 uptake. Large range in the modeled global inventory (+-30%) are largely due to differences in ventilation from the high latitudes. In the southern ocean, models differ particularly in the longitudinal distribution of the CFC uptake in the intermediate water, while the latidudinal distribution is mainly controlled by the subgrid-scale parameterization. More realistic intermediate water ventilation was found in all the models that use isopycnal diffusion and eddy induced velocity parametrization. Deep and bottom water ventilation also varies substantially between the models. Models coupled to a sea-ice model systematically provide more realistic AABW formation source region; however these same models also largely overestimate AABW ventilation if no specific parametrization of brine rejection during sea-ice formation is included. All models exhibit a systematic large underestimation of the CFC uptake in the thermocline of the Pacific subtropical gyre.


back to Publications Gian-Kasper Plattner