The 1D run.def Input File

2026-06-12T14:05:44Z

Jbclement: Created page with "== The run.def input file and its format == === some general comments and disambiguation to start with === This pages specifically focuses on the ''run.def'' file used by the..."

== The run.def input file and its format ==

=== some general comments and disambiguation to start with ===
This pages specifically focuses on the ''run.def'' file used by the 1D version of the Generic PCM.

The run.def file is very similar to the [[The_run.def_Input_File|'''run.def''']] file, with the difference that the 3D options (linked to the dynamic core) are not used, and a whole bunch of new 1D-specific options (information contained in the start and startfi files) are now in the 1D run.def file. Especially, the 1D file has to hold the key <code>run_1d=.true.</code>.

== Reference def files ==
Reference *.def files are provided in the LMDZ.GENERIC/deftank directory

== Outputted used_*def files ==
When the GCM run finishes, for each of the input def files *.def, an ASCII output file '''used_*.def''' is generated (in practice this would be '''used_run.def''' and '''used_callphys.def''' for the 1D simulations). These files contain, along the same format as the *.def input files, the "key = value" that were used, along with comments about whether "value" was read in the input def file or if the code default was used (i.e. the sought "keyword" was not present in the input def files).

== Example of 1D ''run.def'' file ==

<pre>
#---------------------------------#
# Run parameters for the 1D model #
#---------------------------------#

run_1d=.true.

## Planetary constants
## ~~~~~~~~~~~~~~~~~~~~~~~
## NB: those are mandatory
## ~~~~~~~~~~~~~~~~~~~~~~~
## LENGTH OF A DAY in s
daysec = 86400.
## GRAVITY in m s-2
g = 3.72
## Radius of the planet, in m
rad = 3390000
## LENGTH OF A YEAR in days
year_day = 3000
## MIN DIST STAR-PLANET in AU [periastron]
periastr = 1.0
## MAX DIST STAR-PLANET in AU [apoastron]
apoastr = 1.0
## DATE OF PERIASTRON in days
peri_day = 0.
## OBLIQUITY in deg
obliquit = 0.
## SURFACE PRESSURE in Pa
psurf = 100000.

## Time integration parameters
## ~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Initial date (in solar days,=0 at Ls=0)
day0 = 0
# Initial local time (in hours, between 0 and 24)
time = 12
# Number of time steps per sol
day_step = 40
# Number of sols to run
ndt = 1000
# Number of steps between each writing in diagfi
diagfi_output_rate=12

## Vertical levels
## ~~~~~~~~~~~~~~~
# hybrid vertical coordinate ? (.true. for hybrid and .false. for sigma levels)
hybrid = .true.
# autocompute vertical discretisation? (useful for exoplanet runs)
autozlevs = .false.
# Ceiling pressure (Pa) ?
pceil = 0.00001

## Thermal properties
## ~~~~~~~~~~~~~~~~~~
# Simulate global averaged conditions ?
global1d = .true.
# Latitude (deg) [only used if global1d = F]
latitude = 0.0
# Solar Zenith angle (deg) [only used if global1d = T]
szangle = 60.
# Force specific heat capacity and molecular mass values
force_cpp = .false.
# Specific heat capacity in J K-1 kg-1 [only used if force_cpp = T]
cpp = 0.
# Molecular mass in g mol-1 [only used if force_cpp = T]
mugaz = 18.
# Albedo of bare ground
albedo = 0.1
# Emissivity of bare ground
emis = 1.0
# Soil thermal inertia (SI)
inertia = 1000.
# Initial CO2 ice on the surface (kg.m-2)
co2ice = 0.

## Wind profile
## ~~~~~~~~~~~~
## zonal eastward component of the geostrophic wind (m/s)
u = 10.
# meridional northward component of the geostrophic wind (m/s)
v = 0.

## Initial atmospheric temperature profile
## ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#
# Type of initial temperature profile
# ichoice=1 Constant Temperature: T=tref
# [Mars] ichoice=2 Savidjari profile (as Seiff but with dT/dz=cte)
# [Mars] ichoice=3 Lindner (polar profile)
# [Mars] ichoice=4 inversion
# [Mars] ichoice=5 Seiff (standard profile, based on Viking entry)
# ichoice=6 constant T + gaussian perturbation (levels)
# ichoice=7 constant T + gaussian perturbation (km)
# ichoice=8 Read in an ascii file "profile"
ichoice = 1
# Reference temperature tref (K)
tref = 300.
# Add a perturbation to profile if isin=1
isin = 0
# peak of gaussian perturbation (for ichoice=6 or 7)
pic = 26.522
# width of the gaussian perturbation (for ichoice=6 or 7)
largeur = 10
# height of the gaussian perturbation (for ichoice=6 or 7)
hauteur = 30.

</pre>

'''Notes''':
* Lines beginning with a hashtag are comments
* values associated to keywords may be logicals, integers, reals or even strings
* The parsing is case-sensitive : "thisparameter=" and "ThisParameter=" are identified as two distinct keywords
* The order in which the parameters are given in the file does not matter (except if a parameter is specified multiple times, clearly a bad idea, and then the last occurrence will prevail).
* Accessing a parameter and its value from ''run.def'' in the Fortran code is done using the '''getin_p''' routine, e.g.:
<syntaxhighlight lang="fortran">
call getin_p("keyword",val)
</syntaxhighlight>
will look for the line with "keyword = " in file ''run.def'' and extract trailing value which will be use to set the value of the '''val''' variable in the code.

[[Category:Inputs]]
[[Category:WhatIs]]

[[Category:Generic-LMDZ]]
[[Category:Generic-1D]]

Generic unicolumn rcm1d program

2026-05-15T09:52:32Z

Jbclement: /* Inputs */

It is possible to run the Gneric PCM in a uni-column (aka "single-column") configuration: this can be done via the '''rcm1d''' program; quite useful form some first studies but also when developing and testing parametrizations.

== Compilation ==
The main program '''rcm1d''' is compiled using the same compilation script, [[The makelmdz fcm GCM Compilation Script|makelmdz_fcm]], as for the 3D Generic lon-lat PCM. Nevertheless, there are few modifications:
* the ''-d'' option requires only one argument, the number of vertical levels;
* the main program to compile is ''rcm1d'' rather than ''gcm''.
So for instance to compile a case for 26 vertical levels one would run something like:
<syntaxhighlight lang="bash">
makelmdz_fcm -arch somearch -d 26 -p generic rcm1d
</syntaxhighlight>
Note that it is possible to compile and run with the XIOS library, which will require compiling in "mpi" mode (required by XIOS), even though the run will be serial:
<syntaxhighlight lang="bash">
makelmdz_fcm -arch somearch -d 26 -p generic -parallel mpi -io xios rcm1d
</syntaxhighlight>

== Inputs ==
Just like the 3D GCM, the ''rcm1d'' program needs some inputs to run. The needed files are:
* <code>z2sig.def</code> for the definition of vertical levels;
* <code>traceur.def</code> for the definition of tracers that the user wants the model to run with;
* <code>callphys.def</code> for the definition of parametrizations that the user wants the model to run with;
* <code>run.def</code> for the run configuration, which is suitable for 1D: see [[The 1D run.def Input File]]. Especially, the 1D file has to hold the key <code>run_1d=.true.</code>.

Unlike the 3D GCMs, the ''rcm1d'' program can run without any start files, which is its default (<code>restart=.false.</code>). In this setup, one can (and often needs) needs to provide initial profiles of each tracer. These consist in files called ''profile_sometracername'' containing column-wise the initial values of the considered tracer. Then, the first line corresponds to the surface tracer and the following lines correspond to the layers. At the end of a 1D simulation, ''rcm1d'' outputs a restart file '''restart.nc''' which can be used as an initial condition for a following run.

If <code>restart=.true.</code> in <code>rcm1d.def</code> then the program will look for start files '''start.nc''' and '''startfi.nc''' and use these as initial conditions.

== Outputs ==
If compiled without XIOS then ''rcm1d'' will output <code>diagfi.nc</code> and <code>stats.nc</code> files, just like the 3D GCM and the optional <code>diagfi.def</code> and <code>stats.def</code> files can be respectively added to specify which variables need be outputted.
Likewise if compiled with XIOS then ''rcm1d'' will output all files as specified in the relevant xml files, just like the 3D GCM.

As mentioned above, at the end of a simulation <code>rcm1d</code> also outputs a '''restart.nc''' file containing the final computed state.

[[Category:Generic-Model]]
[[Category:Generic-1D]]

Planets - New pages [en]

The 1D run.def Input File

Generic unicolumn rcm1d program