CESM2.0.0 DOCN2.0 CASEROOT Variable Definitions

Name of ocn component

 DOCN mode. The data ocean component (DOCN) always returns SSTs to the
    driver. The atmosphere/ocean fluxes are computed in the
    coupler. Therefore, the data ocean model does not compute fluxes like
    the data ice model. DOCN has two distinct modes of operation. It can
    run as a pure data model, reading in ocean SSTs (normally
    climatological) from input datasets, performing time/spatial
    interpolations, and passing these to the coupler. Alternatively,
    DOCN can compute updated SSTs by running as a slab ocean model where
    bottom ocean heat flux convergence and boundary layer depths are read
    in and used with the atmosphere/ocean and ice/ocean fluxes obtained
    from the driver.
    --- A setting of prescribed assumes the only field in the input stream is SST.
    It also assumes the SST is in Celsius and must be converted to Kelvin.
    All other fields are set to zero except for ocean salinity, which is set to a
    constant reference salinity value. Normally the ice fraction data is found in
    the same data files that provide SST data to the data ocean model. They are
    normally found in the same file because the SST and ice fraction data are derived
    from the same observational data sets and are consistent with each other.
    --- Settings of som (slab ocean model) or  som_aquap (aquaplanet slab ocean) are
    prognostic modes which compute a prognostic sea surface temperature and a
    freeze/melt potential (surface Q-flux) used by the sea ice model.  This
    calculation requires an external SOM forcing data file that includes
    ocean mixed layer depths and bottom-of-the-slab Q-fluxes.
    Scientifically appropriate bottom-of-the-slab Q-fluxes are normally
    ocean resolution dependent and are derived from the ocean model output
    of a fully coupled CCSM run.  Note that while this mode runs out of
    the box, the default SOM forcing file is not scientifically
    appropriate and is provided for testing and development purposes only.
    Users must create scientifically appropriate data for their particular
    application.  A tool is available to derive valid SOM forcing.
    --- A setting of sst_aquapN (where "N" is an integer index value) is a
    type of prescribed SST mode used specifically for an aquaplanet setup in
    which global SSTs correspond to an analytic form set by the index value.
    Currently, indices for 10 SST profiles are supported [e.g., index 3 corresponds
    to the "QOBS" profile of Neale and Hoskins (2001, Atmos. Sci. Lett.)].
    With source code modifications, it is possible for users to create their own
    analytic SST distributions and match them to indices 11 or greater.
    

Sets SOM forcing filename.
    This is only used when DOCN_MODE=som.

Sets aquaplanet forcing filename instead of using an analytic form.
    This is only used when DOCN_MODE=sst_aquapfile.

Prescribed SST and ice coverage stream name.
    Sets SST and ice coverage stream name.
    This is only used when DOCN_MODE=prescribed.

Prescribed SST and ice coverage data file name.
    Sets SST and ice coverage data file name.
    This is only used when DOCN_MODE=prescribed.

Prescribed SST and ice coverage grid file name.
    Sets SST and ice coverage grid file name for prescribed runs.
    This is only used when DOCN_MODE=prescribed.

The model year that corresponds to SSTICE_YEAR_START on the data file.
    Prescribed SST and ice coverage data will be aligned so that the first year of
    data corresponds to SSTICE_YEAR_ALIGN in the model. For instance, if the first
    year of prescribed data is the same as the first year of the model run, this
    should be set to the year given in RUN_STARTDATE.
    If SSTICE_YEAR_ALIGN is later than the model's starting year, or if the model is
    run after the prescribed data ends (as determined by SSTICE_YEAR_END), the
    default behavior is to assume that the data from SSTICE_YEAR_START to
    SSTICE_YEAR_END cyclically repeats. This behavior is controlled by the
    "taxmode" stream option; see the data model documentation for more details.
    This is only used when DOCN_MODE=prescribed.

The first year of data to use from SSTICE_DATA_FILENAME.
    This is the first year of prescribed SST and ice coverage data to use. For
    example, if a data file has data for years 0-99, and SSTICE_YEAR_START is 10,
    years 0-9 in the file will not be used.
    This is only used when DOCN_MODE=prescribed.

The last year of data to use from SSTICE_DATA_FILENAME.
    This is the last year of prescribed SST and ice coverage data to use. For
    example, if a data file has data for years 0-99, and value is 49,
    years 50-99 in the file will not be used.
    This is only used when DOCN_MODE=prescribed.