Marti O. auteur aut IRD Braconnot P. auteur aut IRD Dufresne J. L. auteur aut IRD Bellier J. auteur aut IRD Benshila R. auteur aut IRD Bony S. auteur aut IRD Brockmann P. auteur aut IRD Cadule P. auteur aut IRD Caubel A. auteur aut IRD Codron F. auteur aut IRD Noblet de N. auteur aut IRD Denvil S. auteur aut IRD Fairhead L. auteur aut IRD Fichefet T. auteur aut IRD Foujols M. A. auteur aut IRD Friedlingstein P. auteur aut IRD Goosse H. auteur aut IRD Grandpeix J. Y. auteur aut IRD Guilyardi E. auteur aut IRD Hourdin F. auteur aut IRD Idelkadi A. auteur aut IRD Kageyama M. auteur aut IRD Krinner G. auteur aut IRD Levy C. auteur aut IRD Madec G. auteur aut IRD Mignot Juliette auteur aut IRD Musat I. auteur aut IRD Swingedouw D. auteur aut IRD Talandier C. auteur aut IRD text journalArticle eng text/pdf born digital access This paper presents the major characteristics of the Institut Pierre Simon Laplace (IPSL) coupled ocean-atmosphere general circulation model. The model components and the coupling methodology are described, as well as the main characteristics of the climatology and interannual variability. The model results of the standard version used for IPCC climate projections, and for intercomparison projects like the Paleoclimate Modeling Intercomparison Project (PMIP 2) are compared to those with a higher resolution in the atmosphere. A focus on the North Atlantic and on the tropics is used to address the impact of the atmosphere resolution on processes and feedbacks. In the North Atlantic, the resolution change leads to an improved representation of the storm-tracks and the North Atlantic oscillation. The better representation of the wind structure increases the northward salt transports, the deep-water formation and the Atlantic meridional overturning circulation. In the tropics, the ocean-atmosphere dynamical coupling, or Bjerknes feedback, improves with the resolution. The amplitude of ENSO (El Nio-Southern oscillation) consequently increases, as the damping processes are left unchanged. specialized Climate Simulations Ocean Atmosphere Coupling Circulation El Nino/Southern oscillation North-Atlantic oscillation Storm-tracks Resolution Coupling 032 34 1 1-26 2010 0930-7575 https://www.documentation.ird.fr/hor/fdi:010048411 10.1007/s00382-009-0640-6 0930-7575 [F B010048411] https://www.documentation.ird.fr/hor/fdi:010048411 https://www.documentation.ird.fr/intranet/publi/2009/12/010048411.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2009-12-21 2017-08-23 fdi:010048411 fre