CESM2.1.3 Driver Namelist Definitions

      sets the diagnotics level of the annual budgets. [0,1,2,3],
      written only if do_budgets variable is .true.,
      0=none,
      1=+net summary budgets,
      2=+detailed lnd/ocn/ice component budgets,
      3=+detailed atm budgets
      default: 1
    

      sets the diagnotics level of the daily budgets. [0,1,2,3],
      written only if do_budgets variable is .true.,
      0=none,
      1=+net summary budgets,
      2=+detailed lnd/ocn/ice component budgets,
      3=+detailed atm budgets
      default: 0
    

      sets the diagnotics level of the instantaneous budgets. [0,1,2,3],
      written only if BUDGETS variable is true
      0=none,
      1=+net summary budgets,
      2=+detailed lnd/ocn/ice component budgets,
      3=+detailed atm budgets
      default: 0
    

      sets the diagnotics level of the longterm budgets written at the end
      of the year. [0,1,2,3],
      written only if do_budgets variable is .true.,
      0=none,
      1=+net summary budgets,
      2=+detailed lnd/ocn/ice component budgets,
      3=+detailed atm budgets,
      default: 1
    

      sets the diagnotics level of the longterm budgets written at the end
      of each run. [0,1,2,3],
      written only if do_budgets variable is .true.,
      0=none,
      1=+net summary budgets,
      2=+detailed lnd/ocn/ice component budgets,
      3=+detailed atm budgets,
      default: 0
    

      logical that turns on diagnostic budgets, false means budgets will never be written
    

      Number of CESM driver instances.  Only used if MULTI_DRIVER is TRUE.
    

      Layout of multi-instance atms (if there are more than 1)
    

      the number of mpi tasks assigned to the atm components.
      set by NTASKS_ATM in env_configure.xml.
    

      the number of threads per mpi task for the atm component.
      set by NTHRDS_ATM in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the atm component.
      set by PSTRID_ATM in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the atm component.
      set by ROOTPE_ATM in env_configure.xml.
    

      the number of mpi tasks assigned to the cpl components.
      set by NTASKS_CPL in env_configure.xml.
    

      the number of threads per mpi task for the cpl component.
      set by NTHRDS_CPL in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the cpl component.
      set by PSTRID_CPL in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the cpl component.
      set by ROOTPE_CPL in env_configure.xml.
    

      Layout of multi-instance external system processor (if there are more than 1)
    

      the number of mpi tasks assigned to the esp components.
      set by NTASKS_ESP in env_configure.xml.
    

      the number of threads per mpi task for the esp component.
      set by NTHRDS_ESP in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the esp component.
      set by PSTRID_ESP in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the esp component.
      set by ROOTPE_ESP in env_configure.xml.
    

      Layout of multi-instance glcs (if there are more than 1)
    

      the number of mpi tasks assigned to the glc components.
      set by NTASKS_GLC in env_configure.xml.
    

      the number of threads per mpi task for the glc component.
      set by NTHRDS_GLC in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the glc component.
      set by PSTRID_GLC in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the glc component.
      set by ROOTPE_GLC in env_configure.xml.
    

      Layout of multi-instance ices (if there are more than 1)
    

      the number of mpi tasks assigned to the ice components.
      set by NTASKS_ICE in env_configure.xml.
    

      the number of threads per mpi task for the ice component.
      set by NTHRDS_ICE in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the ice component.
      set by PSTRID_ICE in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the ice component.
      set by ROOTPE_ICE in env_configure.xml.
    

      Layout of multi-instance lnds (if there are more than 1)
    

      the number of mpi tasks assigned to the lnd components.
      set by NTASKS_LND in env_configure.xml.
    

      the number of threads per mpi task for the lnd component.
      set by NTHRDS_LND in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the lnd component.
      set by PSTRID_LND in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the lnd component.
      set by ROOTPE_LND in env_configure.xml.
    

      Layout of multi-instance ocns (if there are more than 1)
    

      the number of mpi tasks assigned to the ocn components.
      set by NTASKS_OCN in env_configure.xml.
    

      the number of threads per mpi task for the ocn component.
      set by NTHRDS_OCN in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the ocn component.
      set by PSTRID_OCN in env_configure.xml.  default: 1
    

      the global mpi task rank of the root processor assigned to the ocn component.
      set by ROOTPE_OCN in env_configure.xml.
    

      Layout of multi-instance lnds (if there are more than 1)
    

      the number of mpi tasks assigned to the lnd components.
      set by NTASKS_LND in env_configure.xml.
    

      the number of threads per mpi task for the lnd component.
      set by NTHRDS_ROF in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the lnd component.
      set by PSTRID_LND in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the lnd component.
      set by ROOTPE_LND in env_configure.xml.
    

      Layout of multi-instance wavs (if there are more than 1)
    

      the number of mpi tasks assigned to the wav components.
      set by NTASKS_WAV in env_configure.xml.
    

      the number of threads per mpi task for the wav component.
      set by NTHRDS_WAV in env_configure.xml.
    

      the mpi global processors stride associated with the mpi tasks for the wav component.
      set by PSTRID_WAV in env_configure.xml.
    

      the global mpi task rank of the root processor assigned to the wav component.
      set by ROOTPE_WAV in env_configure.xml.
    

      if true use  Mahrt and Sun 1995,MWR modification to surface flux calculation
    

      Only used for C,G compsets: if true, compute albedos to work with daily avg SW down
    

      Iterate atmocn flux calculation to this % difference
      Setting this to zero will always do flux_max_iteration
    

      If true, turn on diurnal cycle in computing atm/ocn fluxes
      default: false
     

      Only used for C,G compsets: if ocn, ocn provides EP balance factor for precip
    

      Iterate atmocn flux calculation a max of this value
    

      Force stop at the next month, day, etc when wall_time_limit is hit
      default: month
    

      Whether to renormalize the surface mass balance (smb) sent from lnd to glc so that the
      global integral on the glc grid agrees with the global integral on the lnd grid.

      Unlike most fluxes, smb is remapped with bilinear rather than conservative mapping weights,
      so this option is needed for conservation. However, conservation is not required in many
      cases, since we often run glc as a diagnostic (one-way-coupled) component.

      Allowable values are:
      'on': always do this renormalization
      'off': never do this renormalization (see WARNING below)
      'on_if_glc_coupled_fluxes': Determine at runtime whether to do this renormalization.
         Does the renormalization if we're running a two-way-coupled glc that sends fluxes
         to other components (which is the case where we need conservation).
         Does NOT do the renormalization if we're running a one-way-coupled glc, or if
         we're running a glc-only compset (T compsets).
         (In these cases, conservation is not important.)

      Only used if running with a prognostic GLC component.

      WARNING: Setting this to 'off' will break conservation when running with an
      evolving, two-way-coupled glc.
    

      wind gustiness factor
    

Freezing point calculation for salt water.

      Wall time limit for run
      default: -1.0
    

      Whether Data Assimilation is on for component atm
    

      Whether Data Assimilation is on for component CPL
    

      Whether Data Assimilation is on for component glc
    

      Whether Data Assimilation is on for component ice
    

      Whether Data Assimilation is on for component lnd
    

      Whether Data Assimilation is on for component ocn
    

      Whether Data Assimilation is on for component rof
    

      Whether Data Assimilation is on for component wav
    

      Error tolerance for differences in atm/land areas in domain checking
      default: 1.0e-07
    

      Error tolerance for differences in atm/land lat/lon in domain checking
      default: 1.0e-12
    

      Error tolerance for differences in atm/land masks in domain checking
      default: 1.0e-13
    

      Error tolerance for differences in fractions in domain checking
      default: 1.0e-02
    

      Error tolerance for differences in ocean/ice lon/lat in domain checking
      default: 1.0e-1
    

      Error tolerance for differences in ocean/ice lon/lat in domain checking
      default: 1.0e-2
    

      Error tolerance for differences in ocean/ice masks in domain checking
      default: 1.0e-06
    

      Specify type of ESMF logging
    

      Ending suffix "postfix" for output log files.
    

      Abort model if coupler timestep wallclock time exceeds this value, ignored if 0,
      if < 0 then use abs(max_cplstep_time)*cktime as the threshold.
      default: 0
    

      Root directory for driver output files
    

      List of files to merge together that contains drv_flds_in namelists
      The paths are relative to the case directory. drv_flds_in include the namelists that
      the driver reads and gives information on additional fields to be passed to different
      components that need to look at the same data.
    

      true => turn on aquaplanet mode in cam
    

      1 => default sst mode for aquaplanet in cam
    

      turns on bfb option in coupler which produce bfb results in the
      coupler on different processor counts.  (default: .false.)
    

      Allow same branch casename as reference casename. If $CASE and $REFCASE are the same and the start_type is
      not startup, then the value of brnch_retain_casename is set to .true.
    

      sets the diagnotics level of the monthy budgets. [0,1,2,3],
      written only if do_budgets variable is .true.,
      0=none,
      1=+net summary budgets,
      2=+detailed lnd/ocn/ice component budgets,
      3=+detailed atm budgets
      default: 1
    

      case description.
    

      case name.
    

cime model

      cpl decomp option (0=default, 1=comp decomp, 2=rearr comp decomp, 3=new single 1d seg
      default: 0
    

      Set the coupler sequencing.
    

      hostname information,
    

      Level of debug output, 0=minimum, 1=normal, 2=more, 3=too much (default: 1)
    

      model doi url
    

      model version documentation,
    

      Driver restart filename.
      (NOTE: Normally THIS IS NOT USED -- Set with RUN_REFCASE and RUN_REFDATE)
    

      mode to start the run up, [startup,branch,continue],
      automatically derived from RUN_TYPE in env_run.xml
    

      location of timing checkpoint output.
    

      location of timing output.
    

      username documentation
    

      logical to write an extra initial coupler history file
    

      turns on coupler history stream for instantaneous atm to coupler fields.
      default: false
    

      turns on coupler history stream for 1-hour average atm to coupler fields.
      default: false
    

      turns on coupler history stream for 1-hour instantaneous atm to coupler fields.
      default: false
    

      turns on coupler history stream for daily average atm to coupler fields.
      default: false
    

      turns on coupler history stream for 3-hour average atm to coupler fields.
      default: false
    

      turns on coupler history stream for 3-hour average atm to coupler precip fields.
      default: false
    

      if true, use double-precision rather than single-precision for
      coupler auxiliary history files
      default: false
    

      turns on coupler history stream for instantaneous land to coupler fields.
      default: false
    

      turns on coupler history stream for annual lnd to coupler glc forcing fields.
      default: false
    

      turns on coupler history stream for average* runoff to coupler fields
      (*despite the lack of an averaging time span in the name).
      Files are written at time-of-day = 00000, and at the end of the run interval,
      even if that time is not 00000.
      Run length less than 24 hours; averaging period is the run length,
      Otherwise; averaging period is 24 hours for files before the last (partial) day,
                 averaging period is the last (partial) day for the last file.
      default: false
    

      writes atm fields in coupler average history files.
      default: true
    

      writes glc fields in coupler average history files.
      default: true
    

      writes ice fields in coupler average history files.
      default: true
    

      writes lnd fields in coupler average history files.
      default: true
    

      writes ocn fields in coupler average history files.
      default: true
    

      writes rof fields in coupler average history files.
      default: true
    

      writes wav fields in coupler average history files.
      default: true
    

      writes xao fields in coupler average history files.
      default: true
    

      Grid for atm ocn flux calc (untested)
      default: ocn
    

      atm to ice flux mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to ice state mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to ice state mapping file for velocity
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to land mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to land mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to ocn flux mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to ocn state mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to ocn state mapping file for velocity
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      atm to wav state mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      ATM_GRID values passed into driver.
    

      glc to ice runoff conservative mapping file
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      glc to land mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      glc to land mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      glc to ocn runoff conservative mapping file for ice runoff
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      glc to ocn runoff conservative mapping file for liquid runoff
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      GLC_GRID values passed into driver.
    

      ice to atm mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      ice to atm mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      ice to wav state mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      ICE_GRID values passed into driver.
    

      land to atm mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      land to atm mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      land to glc mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      land to glc mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      lnd to runoff conservative mapping file
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      LND_GRID values passed into driver.
    

      mct alltoall mapping flag
      default: false
    

      mct vector flag
      default: false
    

      ocn to atm mapping file for fluxes
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      ocn to atm mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      ocn to wav state mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      OCN_GRID values passed into driver.
    

      runoff to lnd conservative mapping file
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      runoff to ocn area overlap conservative mapping file
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      runoff to ocn nearest neighbor plus smoothing conservative mapping file
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      runoff to ocn nearest neighbor plus smoothing conservative mapping file
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      ROF_GRID values passed into driver.
    

      invoke pole averaging corrections in shr_map_mod weights generation (default: true)
    

      vect_map
      turns on the vector mapping option for u and v vector mapping between
      atm and ocean grids in the coupler.  the options are none, npfix,
      cart3d, cart3d_diag, cart3d_uvw, and cart3d_uvw_diag.  the none option
      results in scalar mapping independently for the u and v field which
      tends to generate large errors near the poles.  npfix is the
      traditional option where the vectors are corrected on the ocean grid
      north of the last latitude line of the atmosphere grid.  the cart3d
      options convert the east (u) and north (v) vectors to 3d (x,y,z)
      triplets, and maps those fields before converting back to the east (u)
      and north (v) directions.  the cart3d ignores the resuling "w"
      velocity.  the cart3d_uvw calculates the resulting u and v vectors by
      preserving the total "u,v,w" speed and the angle of the (u,v) vector.
      the _diag options just add diagnotics to the log file about the vector
      mapping.
    

      wav to ocn state mapping file for states
    

      The type of mapping desired, either "source" or "destination" mapping.
      X is associated with rearrangement of the source grid to the
      destination grid and then local mapping.  Y is associated with mapping
      on the source grid and then rearrangement and sum to the destination
      grid.
    

      WAV_GRID values passed into driver.
    

      eccentricity of orbit, used when orb_mode is fixed_parameters.
      default: SHR_ORB_UNDEF_REAL (1.e36) (Not currently used in build-namelist)
    

      year of orbit, used when orb_mode is fixed_year or variable_year. (default: 1990)
    

      model year associated with orb_iyear when orb_mode is variable_year. (default: 1990)
    

      orbital model setting.  this sets how the orbital mode will be
      configured.
      "fixed_year" uses the orb_iyear and other orb inputs are ignored.  In
      this mode, the orbital parameters are constant and based on the year.
      "variable_year" uses the orb_iyear and orb_iyear_align.  In this mode,
      the orbital parameters vary as the model year advances and the model
      year orb_iyear_align has the equivalent orbital year of orb_iyear.
      "fixed_parameters" uses the orb_eccen, orb_mvelp, and orb_obliq to set
      the orbital parameters which then remain constant through the model
      integration. [fixed_year, variable_year, fixed_parameters]  (default: 'fixed_year'.)
    

      location of vernal equinox in longitude degrees, used when orb_mode is fixed_parameters.
      default: SHR_ORB_UNDEF_REAL (1.e36)(Not currently used in build-namelist)
    

      obliquity of orbit in degrees, used when orb_mode is fixed_parameters.
      default: SHR_ORB_UNDEF_REAL (1.e36) (Not currently used in build-namelist)
    

      turn on run time control of threading per pe per component by the driver
      default: false
    

      See gptl_papi.c for the list of valid values
    

      See gptl_papi.c for the list of valid values
    

      See gptl_papi.c for the list of valid values
    

      See gptl_papi.c for the list of valid values
    

      default: .false.
    

      default: 1
    

      default: .false.
    

      default: .false.
    

      default: .false.
    

      future asynchronous IO capability (not currently supported).
      If pio_async_interface is .true. or {component}_PIO_* variable is not set or set to -99
      the component variable will be set using the pio_* value.
      default: .false.
    

      blocksize for pio box rearranger
    

      pio buffer size limit
    

      pio debug level
      valid values: 0,1,2,3,4,5,6
    

      pio rearranger communication option: Enable handshake (comp2io)
    

      pio rearranger communication option: Enable handshake (io2comp)
    

      pio rearranger communication option: Enable isends (comp2io)
    

      pio rearranger communication option: Enable isends (io2comp)
      default: .false.
    

      pio rearranger communication flow control direction.
    

      pio rearranger communication max pending req (comp2io)
    

      pio rearranger communication max pending req (io2comp)
    

      pio rearranger communication type.
      valid values: p2p, coll, default
    

      Tolerance for relative error
      default: -1.0e-8
    

      Recompute with non-scalable algorithm if reprosum_diffmax is exceeded.
      default: .false.
    

      Use faster method for reprosum, but one where reproducibility is not always guaranteed.
      default: .false.
    

      New fields that are user specidied can be added as namelist variables
      by the user in the cpl namelist seq_flds_user using the namelist variable
      array cplflds_customs. The user specified new fields must follow the
      above naming convention.
      As an example, say you want to add a new state 'foo' that is passed
      from the land to the atm - you would do this as follows
      &seq_flds_user
      cplflds_custom = 'Sa_foo->a2x', 'Sa_foo->x2a'
      /
      This would add the field 'Sa_foo' to the character strings defining the
      attribute vectors a2x and x2a. It is assumed that code would need to be
      introduced in the atm and land components to deal with this new attribute
      vector field.
      Modify user_nl_cpl to edit this.
    

      If set to .true. BGC fields will be passed back and forth between the ocean and seaice
      via the coupler.
    

      If CCSM_BGC is set to 'CO2_DMSA', then flds_co2_dmsa will be set to .true. by default.
    

      If set to .true., adds prognostic CO2 and diagnostic CO2 at the lowest
      model level to be sent from the atmosphere to the land and ocean.
      If CCSM_BGC is set to 'CO2A', then flds_co2a will be set to .true. by default
    

      If set to .true., adds prognostic CO2 and diagnostic CO2 at the lowest
      model level to be sent from the atmosphere just to the land, and the
      surface upward flux of CO2 to be sent from the land back to the
      atmosphere.
      If CCSM_BGC is set to 'CO2B', then flds_co2b will be set to .true. by default.
    

      If set to .true., adds prognostic CO2 and diagnostic CO2 at the lowest
      model level to be sent from the atmosphere to the land and ocean, and the
      surface upward flux of CO2 to be sent from the land and the open ocean
      back to the atmosphere.
      If CCSM_BGC is set to 'CO2C', then flds_co2c will be set to .true. by default.
    

      Pass water isotopes between components
    

      Number of cism elevation classes. Set by the xml variable GLC_NEC in env_run.xml
    

      Number of sea ice thickness categories. Set by the xml variable ICE_NCAT in env_build.xml
    

      .true. means that all fields passed to coupler are checked for NaN values
    

      .true. if select per ice thickness category fields are passed to the ocean.
      Set by the xml variable CPL_I2O_PER_CAT in env_run.xml
    

       minimum wind speed for atmOcn flux calculations
    

       Surface albedo for direct radiation
    

       Surface albedo for diffuse radiation
    

      grid point latitude associated with single column mode.
      if set to -999, ignore this value
    

      grid point longitude associated with single column mode.
      set by PTS_LON in env_run.xml.
    

      turns on single column mode. set by PTS_MODE in env_case.xml, default: false
    

      atm coupling interval in seconds
      set via ATM_NCPL in env_run.xml.
      ATM_NCPL is the number of times the atm is coupled per NCPL_BASE_PERIOD
      NCPL_BASE_PERIOD is also set in env_run.xml and is the base period
      associated with NCPL coupling frequency, and has valid values: hour,day,year,decade
    

      atm coupling interval offset in seconds default: 0
    

      Sets model barriers with barrier_option and barrier_ymd (same options as stop_n)
      default: 1
    

      sets the driver barrier frequency to sync models across all tasks with barrier_n and barrier_ymd
      barrier_option alarms are like restart_option
      default: never
    

      Date in yyyymmdd format, sets model barriers date with barrier_option and barrier_n
    

      calendar in use.  [NO_LEAP, GREOGORIAN].
      set by CALENDAR in env_build.xml
    

      true => write restarts at end of run
      forces a restart write at the end of the run in addition to any
      setting associated with rest_option.  default=true.  this setting
      will be set to false if restart_option is none or never.
      default: false
    

      esp run interval in seconds
      esp_cpl_dt is the number of times the esp is run per NCPL_BASE_PERIOD
      NCPL_BASE_PERIOD is set in env_run.xml and is the base period
      associated with NCPL coupling frequency, nad has valid values: hour,day,year,decade
      default value set by buildnml to be the pause interval if pause is active
      otherwise, it is set to the shortest component coupling time
    

      esp coupling interval offset in seconds default: 0
    

      true => ESP component runs after driver 'pause cycle' If any
      component 'pauses' (see PAUSE_OPTION,
      PAUSE_N and DATA_ASSIMILATION_XXX XML
      variables), the ESP component (if present) will be run to
      process the component 'pause' (restart) files and set any
      required 'resume' signals.  If true, esp_cpl_dt and
      esp_cpl_offset settings are ignored.  default: true
    

      Period at which coupler averages fields sent to GLC.
      This supports doing the averaging to GLC less frequently than GLC is called
      (i.e., separating the averaging frequency from the calling frequency).
      This is useful because there are benefits to only averaging the GLC inputs
      as frequently as they are really needed (yearly for CISM), but GLC needs to
      still be called more frequently than that in order to support mid-year restarts.

      Setting glc_avg_period to 'glc_coupling_period' means that the averaging is
      done exactly when the GLC is called (governed by GLC_NCPL).
    

      glc coupling interval in seconds
      set via GLC_NCPL in env_run.xml.
      GLC_NCPL is the number of times the glc is coupled per NCPL_BASE_PERIOD
      NCPL_BASE_PERIOD is also set in env_run.xml and is the base period
      associated with NCPL coupling frequency, nad has valid values: hour,day,year,decade
    

      glc coupling interval offset in seconds default: 0
    

      Sets coupler time-average history file frequency (like restart_option)
      set by AVGHIST_N in env_run.xml.
    

      coupler time average history option (used with histavg_n and histavg_ymd)
      set by AVGHIST_OPTION in env_run.xml.
      histavg_option alarms are:
      [none/never], turns option off
      [nstep/s]   , history snapshot every histavg_n nsteps  , relative to current run start time
      [nsecond/s] , history snapshot every histavg_n nseconds, relative to current run start time
      [nminute/s] , history snapshot every histavg_n nminutes, relative to current run start time
      [nhour/s]   , history snapshot every histavg_n nhours  , relative to current run start time
      [nday/s]    , history snapshot every histavg_n ndays   , relative to current run start time
      [monthly/s] , history snapshot every           month   , relative to current run start time
      [nmonth/s]  , history snapshot every histavg_n nmonths , relative to current run start time
      [nyear/s]   , history snapshot every histavg_n nyears  , relative to current run start time
      [date]      , history snapshot at histavg_ymd value
      [ifdays0]   , history snapshot at histavg_n calendar day value and seconds equal 0
      [end]       , history snapshot at end
    

      date associated with histavg_option date.  yyyymmdd format.
      set by AVGHIST_DATE in env_run.xml.
    

      sets coupler snapshot history file frequency (like restart_n)
      set by HIST_N in env_run.xml.
    

      coupler history snapshot option (used with history_n and history_ymd)
      set by HIST_OPTION in env_run.xml.
      history_option alarms are:
      [none/never], turns option off
      [nstep/s]   , history snapshot every history_n nsteps  , relative to current run start time
      [nsecond/s] , history snapshot every history_n nseconds, relative to current run start time
      [nminute/s] , history snapshot every history_n nminutes, relative to current run start time
      [nhour/s]   , history snapshot every history_n nhours  , relative to current run start time
      [nday/s]    , history snapshot every history_n ndays   , relative to current run start time
      [monthly/s] , history snapshot every           month   , relative to current run start time
      [nmonth/s]  , history snapshot every history_n nmonths , relative to current run start time
      [nyear/s]   , history snapshot every history_n nyears  , relative to current run start time
      [date]      , history snapshot at history_ymd value
      [ifdays0]   , history snapshot at history_n calendar day value and seconds equal 0
      [end]       , history snapshot at end
    

      date associated with history_option date.  yyyymmdd format.
      set by HIST_DATE in env_run.xml.
    

      ice coupling interval in seconds
      set via ICE_NCPL in env_run.xml.
      ICE_NCPL is the number of times the ice is coupled per NCPL_BASE_PERIOD
      NCPL_BASE_PERIOD is also set in env_run.xml and is the base period
      associated with NCPL coupling frequency, nad has valid values: hour,day,year,decade
    

      ice coupling interval offset in seconds default: 0
    

      lnd coupling interval in seconds
      set via LND_NCPL in env_run.xml.
      LND_NCPL is the number of times the lnd is coupled per NCPL_BASE_PERIOD
      NCPL_BASE_PERIOD is also set in env_run.xml and is the base period
      associated with NCPL coupling frequency, nad has valid values: hour,day,year,decade
    

      lnd coupling interval offset in seconds default: 0
    

      ocn coupling interval in seconds
      set via OCN_NCPL in env_run.xml.
      OCN_NCPL is the number of times the ocn is coupled per NCPL_BASE_PERIOD
      NCPL_BASE_PERIOD is also set in env_run.xml and is the base period
      associated with NCPL coupling frequency, nad has valid values: hour,day,year,decade
    

      ocn coupling interval offset in seconds default: 0
    

      Whether Pause signals are active for component atm
    

      Whether Pause signals are active for component CPL
    

      Whether Pause signals are active for component glc
    

      Whether Pause signals are active for component ice
    

      Whether Pause signals are active for component lnd
    

      Whether Pause signals are active for component ocn
    

      Whether Pause signals are active for component rof
    

      Whether Pause signals are active for component wav
    

      Sets the pause frequency with pause_option
    

      sets the pause frequency with pause_n
      pause_option alarms are:
      [none/never], turns option off
      [nstep/s]   , pauses every pause_n nsteps  , relative to start or last pause time
      [nsecond/s] , pauses every pause_n nseconds, relative to start or last pause time
      [nminute/s] , pauses every pause_n nminutes, relative to start or last pause time
      [nhour/s]   , pauses every pause_n nhours  , relative to start or last pause time
      [nday/s]    , pauses every pause_n ndays   , relative to start or last pause time
      [nmonth/s]  , pauses every pause_n nmonths , relative to start or last pause time
      [monthly/s] , pauses every        month    , relative to start or last pause time
      [nyear/s]   , pauses every pause_n nyears  , relative to start or last pause time
    

      Sets model restart writes with restart_option and restart_ymd (same options as stop_n)
    

      sets the restart frequency with restart_n and restart_ymd
      restart_option alarms are:
      [none/never], turns option off
      [nstep/s]   , restarts every restart_n nsteps  , relative to current run start time
      [nsecond/s] , restarts every restart_n nseconds, relative to current run start time
      [nminute/s] , restarts every restart_n nminutes, relative to current run start time
      [nhour/s]   , restarts every restart_n nhours  , relative to current run start time
      [nday/s]    , restarts every restart_n ndays   , relative to current run start time
      [monthly/s] , restarts every           month   , relative to current run start time
      [nmonth/s]  , restarts every restart_n nmonths , relative to current run start time
      [nyear/s]   , restarts every restart_n nyears  , relative to current run start time
      [date]      , restarts at restart_ymd value
      [ifdays0]   , restarts at restart_n calendar day value and seconds equal 0
      [end]       , restarts at end
    

      Date in yyyymmdd format, sets model restart write date with rest_option and restart_n
      default: STOP_N
    

      river runoff coupling interval in seconds
      currently set by default to 10800 seconds.
      default: 10800
    

      Start time-of-day in universal time (seconds), should be between zero and 86400
      default: 0
    

      Run start date in yyyymmdd format, only used for startup and hybrid runs.
      default: 00010101
    

      Sets the run length with stop_option and stop_ymd
    

      sets the run length with stop_n and stop_ymd
      stop_option alarms are:
      [none/never], turns option off
      [nstep/s]   , stops every stop_n nsteps  , relative to current run start time
      [nsecond/s] , stops every stop_n nseconds, relative to current run start time
      [nminute/s] , stops every stop_n nminutes, relative to current run start time
      [nhour/s]   , stops every stop_n nhours  , relative to current run start time
      [nday/s]    , stops every stop_n ndays   , relative to current run start time
      [nmonth/s]  , stops every stop_n nmonths , relative to current run start time
      [monthly/s] , stops every        month   , relative to current run start time
      [nyear/s]   , stops every stop_n nyears  , relative to current run start time
      [date]      , stops at stop_ymd value
      [ifdays0]   , stops at stop_n calendar day value and seconds equal 0
      [end]       , stops at end
    

      date in yyyymmdd format, sets the run length with stop_option and stop_n,
      can be in addition to stop_option and stop_n, negative value implies off
    

      Sets timing output file frequency (like restart_n)
    

      Sets timing output file frequency (like rest_option but relative to run start date)
      tprof_option alarms are:
      [none/never], turns option off
      [nstep/s]   , every tprof_n nsteps  , relative to current run start time
      [nsecond/s] , every tprof_n nseconds, relative to current run start time
      [nminute/s] , every tprof_n nminutes, relative to current run start time
      [nhour/s]   , every tprof_n nhours  , relative to current run start time
      [nday/s]    , every tprof_n ndays   , relative to current run start time
      [monthly/s] , every         month   , relative to current run start time
      [nmonth/s]  , every tprof_n nmonths , relative to current run start time
      [nyear/s]   , every tprof_n nyears  , relative to current run start time
      [date]      , at tprof_ymd value
      [ifdays0]   , at tprof_n calendar day value and seconds equal 0
      [end]       , at end
    

      yyyymmdd format, sets timing output file date (like restart_date)
    

      wav coupling interval in seconds
      set via WAV_NCPL in env_run.xml.
      WAV_NCPL is the number of times the wav is coupled per NCPL_BASE_PERIOD
      NCPL_BASE_PERIOD is also set in env_run.xml and is the base period
      associated with NCPL coupling frequency, nad has valid values: hour,day,year,decade
    

      wav coupling interval offset in seconds default: 0
    

      Type of water vapor saturation vapor pressure scheme employed. 'GoffGratch' for
      Goff and Gratch (1946); 'MurphyKoop' for Murphy and Koop (2005); 'Bolton' for
      Bolton (1980); 'Flatau' for Flatau, Walko, and Cotton (1992).
      Default: GoffGratch
    

      Temperature resolution of saturation vapor pressure lookup tables in Kelvin.
      (This is only used if wv_sat_use_tables is .true.)
      Default: 1.0
    

      Width of the liquid-ice transition range in mixed-phase water saturation vapor
      pressure calculations. The range always ends at 0 degrees Celsius, so this
      variable only affects the start of the transition.
      Default: 20K
      WARNING: CAM is tuned to the default value of this variable. Because it affects
      so many different parameterizations, changes to this variable may require a
      significant retuning of CAM's cloud physics to give reasonable results.
    

      Whether or not to produce lookup tables at init time to use as a cache for
      saturation vapor pressure.
      Default: .false.