Articles | Volume 6, issue 1
Geosci. Model Dev., 6, 179–206, 2013

Special issue: The Modular Earth Submodel System (MESSy) (ACP/GMD inter-journal...

Special issue: The Atmospheric Chemistry and Climate Model Intercomparison...

Geosci. Model Dev., 6, 179–206, 2013

Model experiment description paper 07 Feb 2013

Model experiment description paper | 07 Feb 2013

The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): overview and description of models, simulations and climate diagnostics

J.-F. Lamarque1, D. T. Shindell2, B. Josse3, P. J. Young5,4,*, I. Cionni6, V. Eyring7, D. Bergmann8, P. Cameron-Smith8, W. J. Collins9,**, R. Doherty10, S. Dalsoren11, G. Faluvegi2, G. Folberth9, S. J. Ghan12, L. W. Horowitz13, Y. H. Lee2, I. A. MacKenzie10, T. Nagashima14, V. Naik15, D. Plummer16, M. Righi7, S. T. Rumbold9, M. Schulz17, R. B. Skeie11, D. S. Stevenson10, S. Strode19,18, K. Sudo14, S. Szopa20, A. Voulgarakis21, and G. Zeng22 J.-F. Lamarque et al.
  • 1NCAR Earth System Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
  • 2NASA Goddard Institute for Space Studies and Columbia Earth Institute, New York, NY, USA
  • 3GAME/CNRM, Météo-France, CNRS – Centre National de Recherches Météorologiques, Toulouse, France
  • 4Cooperative Institute for Research in the Environmental Sciences, University of Colorado-Boulder, Boulder, CO, USA
  • 5Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
  • 6Agenzia nazionale per le nuove tecnologie, l'energia e lo sviluppo economico sostenibile (ENEA), Bologna, Italy
  • 7Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
  • 8Lawrence Livermore National Laboratory, Livermore, CA, USA
  • 9Hadley Centre for Climate Prediction, Met Office, Exeter, UK
  • 10School of Geosciences, University of Edinburgh, Edinburgh, UK
  • 11Center for International Climate and Environmental Research-Oslo (CICERO), Oslo, Norway
  • 12Pacific Northwest National Laboratory, Richland, WA, USA
  • 13NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
  • 14Frontier Research Center for Global Change, Japan Marine Science and Technology Center, Yokohama, Japan
  • 15UCAR/NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
  • 16Canadian Centre for Climate Modeling and Analysis, Environment Canada, Victoria, British Columbia, Canada
  • 17Meteorologisk Institutt, Oslo, Norway
  • 18NASA Goddard Space Flight Center, Greenbelt, MD, USA
  • 19Universities Space Research Association, Columbia, MD, USA
  • 20Laboratoire des Sciences du Climat et de l'Environnement, CEA/CNRS/UVSQ/IPSL, Gif-sur-Yvette, France
  • 21Department of Physics, Imperial College, London, UK
  • 22National Institute of Water and Atmospheric Research, Lauder, New Zealand
  • *now at: Lancaster Environment Centre, Lancaster University, Lancaster, UK
  • **now at: Department of Meteorology, University of Reading, UK

Abstract. The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) consists of a series of time slice experiments targeting the long-term changes in atmospheric composition between 1850 and 2100, with the goal of documenting composition changes and the associated radiative forcing. In this overview paper, we introduce the ACCMIP activity, the various simulations performed (with a requested set of 14) and the associated model output. The 16 ACCMIP models have a wide range of horizontal and vertical resolutions, vertical extent, chemistry schemes and interaction with radiation and clouds. While anthropogenic and biomass burning emissions were specified for all time slices in the ACCMIP protocol, it is found that the natural emissions are responsible for a significant range across models, mostly in the case of ozone precursors. The analysis of selected present-day climate diagnostics (precipitation, temperature, specific humidity and zonal wind) reveals biases consistent with state-of-the-art climate models. The model-to-model comparison of changes in temperature, specific humidity and zonal wind between 1850 and 2000 and between 2000 and 2100 indicates mostly consistent results. However, models that are clear outliers are different enough from the other models to significantly affect their simulation of atmospheric chemistry.