DART Documentation Main Index
dart_to_roms is the program that updates
a ROMS netCDF-format restart file (usually linked to
"roms_restart.nc") with the state information contained
in a DART output/restart file
(e.g. perfect_ics, filter_ics).
THIS IS NOT IMPLEMENTD YET:
the DART model time is compared to the time in the ROMS 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_roms 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_roms_nml:advance_time_present = .false. .
During perfect_model_obs or filter, the &dart_to_roms_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_roms:
dart_to_roms and roms_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 ROMS grid and restart filenames - roms_grid.nc and roms_restart.nc, respectively.
dart_to_roms was originally written by Peng Xiu of the University of Maine and was subsequently modified by the DART team.
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_roms_nml dart_to_roms_input_file = 'dart.restart' print_data_ranges = .true. advance_time_present = .false. time_filename = 'roms_time' /
&model_nml analysis_time = '2011-01-03 00:00:00' output_state_vector = .false. assimilation_period_days = 5 assimilation_period_seconds = 0 model_perturbation_amplitude = 0.2 hc = 250.0 model_restart_filename = 'roms_restart.nc' grid_definition_filename = 'roms_grid.nc' vert_localization_coord = 3 debug = 1 variables = 'temp', 'KIND_TEMPERATURE', 'salt', 'KIND_SALINITY', 'u', 'KIND_U_CURRENT_COMPONENT', 'v', 'KIND_V_CURRENT_COMPONENT', 'zeta', 'KIND_SEA_SURFACE_HEIGHT' /
The dart_to_roms namelist items:
|dart_to_roms_input_file||character(len=256)||The name of the DART file containing the model state to insert into the ROMS 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 text file is created that contains time information that can be conveyed to ROMS to control the desired model advance.|
|print_data_ranges||logical||switch to print a summary of the min/max of each variable that will be part of the DART vector.|
|time_filename||character(len=256)||The name of the text file containing the time information to specify the next ROMS model advance. This is usually simply roms_time but may be anything, as long as advance_model.csh is consistent.|
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 ROMS model_mod documentation, but the most important variable for dart_to_roms is repeated here.
|analysis_time||character(len=20)||At present, this is a way to specify the valid time of the LAST timestep in the ROMS restart file. When the restart file has enough metadata to determine this, the analysis_time should be removed. An alternate way to override the file-derived start time is to use the input.nml &filter_nml: init_time_days, init_time_seconds mechanism.|
|variables|| character(len=NF90_MAX_NAME) ::
|The list of variable names in the ROMS restart file to use to create the DART state vector and their corresponding DART kind.|
assim_model_mod location_mod model_mod null_mpi_utilities_mod obs_kind_mod random_seq_mod time_manager_mod types_mod utilities_mod
none - all error messages come from modules that have their own documentation.
DART software - Copyright 2004 - 2013 UCAR.
This open source software is provided by UCAR, "as is",
|Contact:||DART core group|
|Revision:||$Revision: 9425 $|
|Source:||$URL: https://svn-dares-dart.cgd.ucar.edu/DART/releases/classic/models/ROMS/dart_to_roms.html $|
|Change Date:||$Date: 2016-01-06 13:20:44 -0700 (Wed, 06 Jan 2016) $|
|Change history:||try "svn log" or "svn diff"|