Connotea
CiteULike
del.ico.us
BibSonomyAbstract
Radiative forcing by well-mixed greenhouse gases: Estimates from climate models in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4)
National Center for Atmospheric Research, Boulder, Colorado, USA
Geophysical Fluid Dynamics Laboratory, Princeton, New Jersey, USA
Geophysical Fluid Dynamics Laboratory, Princeton, New Jersey, USA
National Climate Center, Beijing, China
Aeronomy Laboratory, NOAA, Boulder, Colorado, USA
Department of Atmospheric Sciences, University of Washington, Seattle, Washington, USA
Department of Meteorology, University of Reading, Reading, UK
Laboratoire de Météorologie Dynamique, Paris, France
Le Laboratoire des Sciences du Climat et l'Environnement, Gif-sur-Yvette, France
School of Earth and Environment, University of Leeds, Leeds, UK
Institute of Numerical Mathematics, Academy of Sciences, Moscow, Russia
Department of Meteorology, University of Reading, Reading, UK
Department of Physics, Clarendon Laboratory, Oxford, UK
NASA Langley Research Center, Hampton, Virginia, USA
Laboratoire de Météorologie Dynamique, Paris, France
Canadian Centre for Climate Modeling and Analysis, University of Victoria, Victoria, British Columbia, Canada
Météo-France, CNRM, Toulouse, France
NASA Goddard Institute for Space Studies, New York, New York, USA
Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan
Meteorological Research Institute, Tsukuba, Japan
Physics Department, Imperial College, London, UK
The radiative effects from increased concentrations of well-mixed greenhouse gases (WMGHGs) represent the most significant and best understood anthropogenic forcing of the climate system. The most comprehensive tools for simulating past and future climates influenced by WMGHGs are fully coupled atmosphere-ocean general circulation models (AOGCMs). Because of the importance of WMGHGs as forcing agents it is essential that AOGCMs compute the radiative forcing by these gases as accurately as possible. We present the results of a radiative transfer model intercomparison between the forcings computed by the radiative parameterizations of AOGCMs and by benchmark line-by-line (LBL) codes. The comparison is focused on forcing by CO2, CH4, N2O, CFC-11, CFC-12, and the increased H2O expected in warmer climates. The models included in the intercomparison include several LBL codes and most of the global models submitted to the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). In general, the LBL models are in excellent agreement with each other. However, in many cases, there are substantial discrepancies among the AOGCMs and between the AOGCMs and LBL codes. In some cases this is because the AOGCMs neglect particular absorbers, in particular the near-infrared effects of CH4 and N2O, while in others it is due to the methods for modeling the radiative processes. The biases in the AOGCM forcings are generally largest at the surface level. We quantify these differences and discuss the implications for interpreting variations in forcing and response across the multimodel ensemble of AOGCM simulations assembled for the IPCC AR4.
Received 26 September 2005; accepted 7 April 2006; published 28 July 2006.
Citation: (2006), Radiative forcing by well-mixed greenhouse gases: Estimates from climate models in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4), J. Geophys. Res., 111, D14317, doi:10.1029/2005JD006713.
Cited By