The authors would like to recognize all the scientists and technical staff of the Global Climate and Weather Modeling Branch of EMC for their hard work and dedication to the development of the GFS. We would also like to extend our thanks to the scientists at GFDL for their work in developing the MOM4. George Vandenberghe, Carolyn Pasti, and Julia Zhu are recognized for their critical support in the smooth running of the CFSv2 retrospective forecasts and the operational implementation of the CFSv2. We also thank Ben Kyger, Dan Starosta, Christine Magee, and Becky Cosgrove from the NCEP Central Operations (NCO) for the timely operational implementation of the CFSv2 in March 2011.
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This paper describes the CFS reanalysis data from 1979–2010 and the CFSv2 retrospective data from 1982–2010. However, both datasets are being updated in real-time operations at NCEP.
CO2 is not increased during a particular hindcast, but through the initial conditions; for example, hindcasts for 2010 are run at much higher CO2 (which is maintained throughout the forecast) than for hindcasts in 1982. In CFSv1, a single CO2 value valid in 1988 was used for all years.
We should point out that what we call the International Multimodel Ensembles (IMME) has its counterpart called Eurosip in Europe. CFSv2 has been included as a member in the Eurosip ensemble, which consists of the European Centre for Medium-Range Weather Forecasts (ECMWF), Met Office (UKMO), and Météo France.