Figure 7.2: Change in the
Top of the Atmosphere (TOA) Cloud Radiative Forcing (CRF) associated with a CO2
doubling (from a review by Le Treut and McAvaney, 2000). The models are coupled
to a slab ocean mixed layer and are brought to equilibrium for present climatic
conditions and for a double CO2 climate. The sign is positive when
an increase of the CRF (from present to double CO2 conditions) increases
the warming, negative when it reduces it. The contribution of the shortwave (SW,
solar) and long-wave (LW, terrestrial) components are first distinguished, and
then added to provide a net effect (black bars). Results presented in the diagram
are bounded by a 3 Wm-2 limit. As in Chapter 8,
Table 8.1, the acronyms refer to the atmospheric models
of the following institutions: BMRC is the Bureau of Meteorology Research Center
(Australia); NCAR is the National Center for Atmospheric Research (USA); CSIRO
is the Commonwealth Scientific and Industrial Research Organization (Australia);
MPI the Max Planck Institute for Meteorology (Germany); UKMO refers to the model
of the Hadley Centre (UK); GFDL is the Geophysical Fluid Dynamics Laboratory (USA);
CCSR is the Center for Climate System Research (Japan); LMD is the Laboratoire
de Météorologie Dynamique (the corresponding coupled model being
referenced as IPSL, France); MRI is the Meteorological Research Institute (Japan).
The MGO model appears only in this intercomparison and is the model of the Main
Geophysical Observatory (Russia) (see reference in Meleshko et al., 2000).