PROGRAM dart_to_clm

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version information for this file:
$Id: dart_to_clm.html 6382 2013-08-07 20:45:16Z nancy $

NAMELIST / MODULES / FILES / REFERENCES / ERRORS / PLANS / TERMS OF USE

Overview

dart_to_clm is the program that updates a CLM netCDF-format restart file (usually linked to "clm_restart.nc") with the state information contained in a DART output/restart file (e.g. perfect_ics, filter_ics). The DART model time is compared to the time in the CLM restart file and if they do not match the program issues an error message and aborts.

While setting up an experiment or for testing purposes, dart_to_clm may be used on DART files that have a header containing one time stamp followed by the model state by setting input.nml &dart_to_clm_nml:advance_time_present = .false. .

During perfect_model_obs or filter, the &dart_to_clm_nml:advance_time_present must be set to .true. to also read the assim_model_state_ic files that have two timestamps in the header. These files are temporarily generated when DART is used to advance the model. One timestamp is the 'advance_to' time, the other is the 'valid_time' of the model state.

Conditions required for successful execution of dart_to_clm:

dart_to_clm and clm_to_dart are used extensively in the shell script assimilate.csh. Since this program is called repeatedly for every ensemble member, we have found it convenient to link the DART input file to the default input filename (dart_restart). The same thing is true for the CLM history and restart filenames - clm_history.nc and clm_restart.nc, respectively.

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NAMELIST

This namelist is read from the file input.nml. Namelists start with an ampersand '&' and terminate with a slash '/'. Character strings that contain a '/' must be enclosed in quotes to prevent them from prematurely terminating the namelist.

&dart_to_clm_nml
   dart_to_clm_output_file      = 'dart_restart',
   advance_time_present         = .false.,
   /

&model_nml
   clm_restart_filename         = 'clm_restart.nc',
   clm_history_filename         = 'clm_history.nc',
   calendar                     = 'Gregorian',
   clm_state_variables          = 'frac_sno',    'KIND_SNOWCOVER_FRAC',
                                  'SNOWDP',      'KIND_SNOW_THICKNESS',
                                  'T_SOISNO',    'KIND_SOIL_TEMPERATURE',
                                  'leafc',       'KIND_LEAF_CARBON'
   /

(partial list)


The dart_to_clm namelist items:

Item Type Description
dart_to_clm_input_file character(len=128) The name of the DART file containing the model state to insert into the CLM restart file.
advance_time_present logical switch to control the ability to read a DART file containing TWO timestamps in the file header. If you are converting a DART initial conditions or restart file this should be .false.; these files have a single timestamp describing the valid time of the model state. If .true., TWO timestamps are expected to be the DART file header. In this case, a namelist for CLM (called clm_in.DART) is created that contains the &time_manager_nml settings appropriate to advance CLM to the time requested by DART.


The &model_nml namelist here is a subset of the full namelist. Only the values used by the converter are listed here. The full description of the model_nml namelist is documented in the CLM model_mod documentation, but the most important variable for dart_to_clm is repeated here.

Item Type Description
clm_state_variables character(len=NF90_MAX_NAME) ::
dimension(160)
The list of variable names in the CLM restart file to use to create the DART state vector and their corresponding DART kind.


For example:

&clm_vars_nml
   clm_state_variables = 'frac_sno',   'KIND_SNOWCOVER_FRAC',
                         'H2OSNO',     'KIND_SNOW_WATER',
                         'SNOWDP',     'KIND_SNOW_THICKNESS',
                         'H2OSOI_LIQ', 'KIND_LIQUID_WATER',
                         'H2OSOI_ICE', 'KIND_ICE',
                         'T_SOISNO',   'KIND_SOIL_TEMPERATURE',
                         'leafc',      'KIND_LEAF_CARBON',
  /
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MODULES USED

assim_model_mod
location_mod
model_mod
null_mpi_utilities_mod
obs_kind_mod
random_seq_mod
time_manager_mod
types_mod
utilities_mod
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FILES Read

FILES Written

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REFERENCES

none

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ERROR CODES and CONDITIONS

none - all error messages come from modules that have their own documentation.

KNOWN BUGS

none

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FUTURE PLANS

None.

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Terms of Use

DART software - Copyright 2004 - 2013 UCAR.
This open source software is provided by UCAR, "as is",
without charge, subject to all terms of use at
http://www.image.ucar.edu/DAReS/DART/DART_download

Contact: DART core group
Revision: $Revision: 6382 $
Source: $URL: https://svn-dares-dart.cgd.ucar.edu/DART/releases/Lanai/models/clm/dart_to_clm.html $
Change Date: $Date: 2013-08-07 14:45:16 -0600 (Wed, 07 Aug 2013) $
Change history:  try "svn log" or "svn diff"