Executables & Namelists

In the following subsection, you can find the list of compiled executables and its corresponding namelists :

• PREP_PGD
• PREP_NEST_PGD
• PREP_IDEAL_CASE
• PREP_REAL_CASE
• SPAWNING
• MESONH
• DIAG
• SPECTRE
• LATLON_TO_XY
• CDF2CDF
• PREP_SURFEX

All the information required to launch a given executable are located in a F90 namelist file. The Meso-NH user can change the value of the parameters without any compilation. These files provide the way for the Meso-NH user to interact with the numerical code and finally, they contain the identification cards of the different steps of the numerical experiment.

The information are written in the following form:

&NAM_LUNITn
  CINIFILE = "INIFILE"
/

&NAM_CONFn
  LUSERV = T,
  LUSERC = F,
  LUSERR = F,
  LUSERI = F,
  LUSERS = F,
  LUSERG = F,
  LUSERH = F,
  NSV    = 0
/

&NAM_LUNITn is the name of the first namelist of this file, the / character indicates the end of the list of information. These namelist parameters are defined by VAR = VALUE and these prescriptions are separated from each others by a comma and a blank character. Note that you can use more than one line to give a namelist, but in this case it is imperative to let a blank character at the end of each line.

Tip

The Meso-NH user does not need to prescribe all the parameters of a namelist, the missing information are taken equal to the default values written in the Fortran code. For example, the second namelist in the previous example can be written as:

&NAM_CONFn
  LUSERV = T
/

because the other variables of &NAM_CONFn are set to the default values.

In order to clearly separate what can be modified for a given step of a numerical experiment, we affect a different namelist file name for each executables :

List of executables and its corresponding namelist and function

Executable	Input namelist file	Function
PREP_PGD	PRE_PGD1.nam	Prepare horizontal grid file
PREP_NEST_PGD	PRE_NEST_PGD1.nam	Prepare horizontal grid file for grid nesting
PREP_IDEAL_CASE	PRE_IDEA1.nam	Prepare initial file for idealized simulation
PREP_REAL_CASE	PRE_REAL1.nam	Prepare initial file for real case simulation
SPAWNING	SPAWN1.nam	Spawn a Meso-NH file into another one with better horizontal resolution
MESONH	EXSEGn.nam	Perform the simulation
DIAG	DIAG1.nam	Compute diagnostic after simulation
SPECTRE	SPEC1.nam	Compute spectra after simulation

Because the grid-nesting technique requires the simultaenous presence of multiple models in the computer memory, free-parameters must be fixed for every model. This is performed by associating a namelist file per model, this explains why the namelist are suffixed by a number 1 or n just above. The different parameters present in these files are all given in this book and more details on the description of a given parameter are present in the code itself.