The Whole-Atmosphere Community Climate Model (WACCM) is a comprehensive numerical model, spanning the range of altitude from the Earth's surface to the thermosphere. The development of WACCM is an inter-divisional collaboration that unifies certain aspects of the upper atmospheric modeling of HAO, the middle atmosphere modeling of ACD, and the tropospheric modeling of CGD, using the NCAR Community Climate System Model (CCSM) as a common numerical framework.

The atmosphere component of CCSM, the Community Atmosphere Model (CAM) has been extended to the thermosphere by:

1. incorporating non-LTE IR transfer above 60 km;
2. including shortwave heating and photolysis from Lyman-alpha to EUV
   
3. extending the parameterization of gravity wave breaking and diffusion above the mesopause;
4. including molecular diffusion and diffusive separation effects; 
   
5. incorporating and extending the chemical scheme from ACD's MOZART-3 photochemistry model

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WACCM and CCSM

WACCM is part of NCAR's Community Climate System Model.  Use the links below for detailed information.

• CCSM Whole Atmosphere Model Working Group

• WACCM mailing list

• CCSM Bulletin Board (under "Whole Atmosphere Modeling with WACCM")