zzz OBSOLETE Output Specifications

Overview

Most output from GEOSldas is generated in netcdf format through the HISTORY functionality provided by MAPL.

Notable exceptions from the MAPL-generated output include:

• log files [ASCII],
• observation-space "ObsFcstAna" data assimilation diagnostics [BINARY], and
• SMAP L4_SM-specific "aup" data assimilation diagnostics files (available only for simulations in EASEv2_M09 tile space) [BINARY].

Output of the latter two sets of files can be turned on/off in the [NML_INPUT_PATH]/LDASsa_SPECIAL_inputs_ensupd.nml configuration file, and Matlab readers are available in the src/Applications/LDAS_App/util directory.

MAPL HISTORY output

During ldas_setup, a sample HISTORY.rc configuration file is created in the experiment's ./run directory. By editing HISTORY.rc, users specify the desired output. HISTORY.rc defines a number of output file "Collections", each of which contains one or more output variables. Output can be gridded ("2d") or in the native tile space ("1d"). All variables contained in a given Collection are written:

• on the same grid (if gridded),
• at the same output frequency (time step), and
• in either time-average ("tavg") or instantaneous ("inst") sampling mode.

In the following example, the tavg3_2d_lnd_Nx Collection contains time-average ("tavg"), 3-hourly ("3"), gridded ("2d", "Nx") data for a set of land variables ("lnd"), and the inst1_1d_lfs_Nt Collection contains snapshot (or instantaneous, "inst"), 1-hourly, tile-space ("1d", "Nt") data for another set of land variables ("lfs").

COLLECTIONS:
            'tavg3_2d_lnd_Nx'
            'inst1_1d_lfs_Nt'
           ::

The Collection names are just strings that become part of the output file names. As such, they are only a convention; any set of unique strings could be used. More information on the naming conventions can be found in the GMAO "Office Notes" on the GEOS-FP and MERRA-2 "File Specification."

The desired list of variables, output time step, resolution, etc. are specified in the Collection definitions, which appear later in HISTORY.rc.

To be available for output through MAPL HISTORY, a variable must be an ExportSpec in a GEOS_*GridComp.F90 file. The list of variables ("fields") in each Collection consists of three columns:

• (column 1) variable name in GEOS_[GCNAME]GridComp.F90 file,
• (column 2) GridComp name [GCNAME], and
• (column 3) user-specified variable name used in nc4 output (optional).

For example, to write the "WCSF" and "WCRZ" ExportSpec variables (surface and root-zone soil moisture) from the Catchment model ("CATCH") GridComp under the names "SFMC" and "RZMC", respectively, into the output nc4 file, the Collection definition for tavg3_2d_lnd_Nx must include the following:

 tavg3_2d_lnd_Nx.mode:        'time-averaged',
 tavg3_2d_lnd_Nx.frequency:   030000,
 tavg3_2d_lnd_Nx.fields:      'WCSF'       , 'CATCH'  , 'SFMC'         ,
                              'WCRZ'       , 'CATCH'  , 'RZMC'         ,
                              ::

The same variable can be written in more than one Collection (i.e., at different temporal and/or spatial resolutions), and there is no limit to the number of Collections that can be defined for and written by a simulation.

Gridded ("2d") output can be on a grid other than the "native" grid that is associated with the tile space used in the simulation, as long as the output grid is defined in HISTORY.rc. [MORE INFO NEEDED!!!]

MAPL HISTORY can generally write gridded ("2d") output in binary or netcdf-4 (nc4) format except for GEOSldas simulations in EASE-grid tile space. Output in tile space ("1d") must be written in binary format.

Special considerations for GEOSldas

1. Gridded ("2d") output cannot be written for simulations in any EASE-grid tile space. But since each EASE-grid cell contains at most one tile, it is straightforward to convert tile-space ("1d") output into gridded output (2d arrays) on the fly using the i_indg and j_indg data in the ./rc_out/*tilecoord* file. See Matlab readers and scripts in ./src/Application/LDAS_App/util.

2. When running in EASE-grid tile space, GEOSldas.x always writes tile-space ("1d") output in binary format using MAPL HISTORY. If nc4 output is requested in HISTORY.rc, the binary output is then automatically converted into nc4 format in post-processing as part of the lenkf.j job script using the tile_bin2nc4.F90 utility.

3. GEOSldas can bundle sub-daily nc4 output into daily nc4 files and write monthly-average output through the POSTPROC_HIST configuration option.