Status and Improvements of Coupled General Circulation Models
Hartmut Grassl
Coupled general circulation models (CGCMs)
integrate our knowledge about atmospheric and oceanic circulation.
Different versions of CGCMs are used to provide a better understanding
of natural climate variability on interannual and decadal time scales,
for extended weather forecasting, and for making seasonal climate scenario projections. They also help to reconstruct past climates, especially abrupt climate change processes. Model intercomparisons, new
test data (mainly from satellites), more powerful computers, and
parameterizations of atmospheric and oceanic processes have improved
CGCM performance to such a degree that the model results are now used
by many decision-makers, including governments. They are also
fundamental for the detection and attribution of climate change.
Max-Planck-Institute for Meteorology, Bundesstrasse 55, D-20146
Hamburg, Germany. E-mail: grassl{at}dkrz.de
