The Climate System Model (CSM) project formally began in January
1994 with the long-term goal of building, maintaining, and
continually improving a comprehensive model of the climate system,
including both physical and biogeochemical aspects. CSM is an
NCAR-wide project centered in CGD with participants from the
Atmospheric Chemistry Division (ACD),
the High Altitude Observatory (HAO), and the Scientific Computing
Division (SCD).
The comprehensive CSM is composed of a set of four independent models for the basic system
components: atmosphere, ocean, land surface, and sea ice, each communicating with a "flux coupler"
using message passing. The component models are driven primarily by fluxes at the Earth's surface.
Those fluxes that directly depend on the state of more than one component model, e.g., turbulent fluxes of
latent and sensible heat, are computed within the flux coupler, which is also responsible for interpolating
and averaging between the differing grids of the component models while conserving local and integral
properties.