• Prognostic Variables Potential temperature; vorticity and divergence; surface pressure; specific humidity; CKE; mixing ratios of cloud water, cloud ice, rain and snow; PBL's depth and TKE; ground temperature and wetness; moisture stores for canopy and soil. Options: CO2

• Sigma Coordinate Generalized sigma coordinate, highly conservative.

• Planetary Boundary Layer Entraining well-mixed layer, stability and roughness dependence. Second- order bulk model being tested.

• Grid Geodesic Grid, highly conservative.

• Microphysics Fowler-Randall-Rutledge microphysics. Cumulus detrainment acts as a source of cloud water and/or ice.

• Cumulus Parameterization Modified Arakawa-Schubert with ice, prognostic cumulus kinetic energy, cumulus friction, multiple cloud bases, and simple convective downdrafts.

• Radiation Harshvardhan, with seasonal and diurnal cycles

• Biosphere SiB II (Sellers et al.), including carbon assimilation.

• Gravity-Wave Drag Simple Palmer-like scheme.

• Boundary Conditions Realistic topography, seasonally varying sea surface temperatures, sea-ice distribution and thickness, vegetation types, surface albedo, and surface roughness.

• Flux Coupler Flux coupler which communicates between the atmosphere and the ocean, and between the atmosphere and the land surface.

• Ocean Prescribed climatological SST and sea ice cover. Options for prescribed SST and ice for specific years, use of a mixed layer ocean with prescribed horizontal heat transport and a simple thermodynamic sea ice model, and use of a dynamic three-dimensional ocean model (POP or TOMS) for all or part of the ocean domain.