Community Atmosphere Model (CAM) namelist options

CAM can be run with a number of dycores (Eulerian, FV, FV3, SE, MPAS), with each set up in the same manner. As such, there are a number of common namelist options which are agnostic to the choice of dynamical core.

Important CAM namelist options:

• analytic_ic_type: The name of the analytic initial condition to use. CAM already has inbuilt initial conditions you can try: 'held_suarez_1994', 'moist_baroclinic_wave_dcmip2016', 'dry_baroclinic_wave_dcmip2016', 'dry_baroclinic_wave_jw2006', 'us_standard_atmosphere'. For DCMIP2025, we have four new initial conditions to try:

  • • Case 1: 'gw_break'

    • Case 2a: 'gap_horiz_mount_flow'

    • Case 2b: 'vortex_horiz_mount_flow'

    • Case 3: 'squall'

• write_nstep0: Whether to output the initial condition. It's a good idea to set this to TRUE.

• empty_htapes: Set to TRUE to ensure no history output is produced.

• avgflag_pertape: Set to 'I' for instantaneous output or 'A' for averaged output.

• MFILT: Number of output timestamps in one output file before a new output file is produced.

• NDENS: Precision of the output, 2 for single-precision output (4 bytes). This is the default, just keep it this way.

• NHTFRQ: Frequency of the output. If this value is positive, it is the number of timesteps. If negative, it is the number of hours.

• fincl1, fincl2, ... etc. : Specify the list of fields to record in output file x. For example, fincl1 = 'U', 'V', 'T', 'OMEGA', 'PS', 'PHIS', 'Z3'

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