The ORCHIDEE_OL configurations

Person in charge: Josefine Ghattas

1. Description

ORCHIDEE_OL is the generic name of the forced ORCHIDEE configurations. They are also called offline configurations. In this context the ORCHIDEE model is forced with climatic variables based on observations or on existing climatic simulations. Following executables can be compiled depending on the version:

• orchidee_ol : the standard driver for complete ORCHIDEE model
• orchideedriver : a new driver to run the complete ORCHIDEE model, this version is under development
• teststomate : Currently not maintained: to allow the vegetation to reach equilibrium
• forcesoil : Currently not maintained: to allow the carbon in the soil to reach equilibrium

2. Extract ORCHIDEE offline configurations

2.1. Extract a predefined configuration

Following predefined configurations exist currently for ORCHIDEE offline use, the install a different version of ORCHIDEE source code:

• ORCHIDEE_trunk : the latest version on the trunk. Be careful: if you use this version the trunk results have not been evaluated! This is often the version which is advised.
• ORCHIDEE_2_2 : a branch created from the tag ORCHIDEE_2_1. This branchs contains bug corrections and new developements needed for DYNAMICO
• ORCHIDEE_2_1 : the most recent tag, created from the trunk before inclusion of the nitrogen cycle in ORCHIDEE
• ORCHIDEE_2_0 : the CMIP6 version of ORCHIDEE
• ORCHIDEE_AR5 : the CMIP5 version, only sources code is extracted without configuration files

The configuration is extracted in modipsl/util using ./model. For example: ./model ORCHIDEE_trunk.

2.2. Extract a branch or another version of ORCHIDEE

If you want to use a branch or a personal version on the SVN file depository of ORCHIDEE, we recommend to change the ORCHIDEE_trunk configuration in mod.def and extract this version with ./model ORCHIDEE_trunk. Go here to learn more about how to change mod.def.

3. Resolution

The compiled executable can be used at all spatial resolutions (from local to global scales). The forcing file or the options in the parameter file determine the domain (LIMIT_WEST, LIMIT_EAST, LIMIT_NORTH and LIMIT_SOUTH) and the spatial resolution (MERID_RES and ZONAL_RES). Default in the configurations is global grid.

The .resol file does not exist for ORCHIDEE_OL because the executables can be used for all resolutions.

4. Compilation

The compiling is done from modipsl/config/ORCHIDEE_OL using

• gmake : the executable orchidee_ol can be used with XIOS or IOIPSL. The executable xios.server is also created.
• gmake without_xios : XIOS is not compiled and can not be used for the output.

Read more about compile methods here: ​https://forge.ipsl.jussieu.fr/orchidee/wiki/Documentation/UserGuide/CompileMethods

5. The experiments

In the ORCHIDEE_OL configuration, there are several directories containing predefined experiments already set up. This means that the submit folder already exists with the config.card and all folders ready inside: COMP, PARAM, POST. Note that the comp.driver files are stored inside the COMP folder together with the comp.card files. You can copy one of the existing folders, change the JobName in config.card and if you need to change other options, then run ../../../libIGCM/ins_job to create the main job.

Following experiments are predefined, they all use the standard driver orchidee_ol except OOL_SEC_STO_FG3nd:

• SPINUP_ANALYTIC_FG1 : Set up with the analytical spinup, full ORCHIDEE model, using CRU-NCEP forcings.
• OOL_SEC_STO_FG1trans : Set up for a transitory simulation to be used after the analytical spinup and before the FG2 simulation, using CRU-NCEP forcings.
• OOL_SEC_STO_FG2 : Set up for historical simulation, by default it starts without restart files but it is recommended to set the start from the OOL_SEC_STO_FG1trans simulation, CRU-NCEP forcings.
• OOL_SEC_STO_FG3 : Set up for historical simulation using WFDEI forcing files, using the orchidee_ol driver
• OOL_SEC_STO_FG3nd : As OOL_SEC_STO_FG3 but using the orchideedriver under development
• OOL_SEC : experiment set up for a simulation with sechiba only (without stomate). You can also perform such an experiment in OOL_SEC_STO by deactivating stomate.

There are 2 other directories containing experiments which have a different structure. These experiments are looping over several sub-jobs and often used for site simulations. This documentation do not describe the usage of these specific experiments, contact the ORCHIDEE group if you need to use them:

• SPINUP : this experiment loops on the various sub-experiments of OOL_SEC_STO, OOL_SEC, TESTSTOMATE and FORCESOIL.
• ENSEMBLE : a chain of SPINUP on the FLUXNET site to validate ORCHIDEE.

The following experiments are currently not maintained in the default version, if you need them, contact the ORCHIDEE group:

• TESTSTOMATE : experiment with the teststomate executable (for the carbon in the vegetation to reach equilibrium).
• FORCESOIL : experiment with the forcesoil executable (for the carbon in the soil to reach equilibrium).

6. XIOS / IOIPSL

By default, XIOS is used to write output files in ORCHIDEE_OL configuration but this can be changed to use IOIPSL instead.

Do the following to compile without XIOS:

cd modipsl/config/ORCHIDEE_OL
gmake without_xios

Switch to IOIPSL output method by changing to following in COMP/orchidee_ol.card:

# Use XIOS as output library instead of IOIPSL
XIOS=n

The control parameters for IOIPSL output can now be changed manually in PARAM/run.def.

Read more about XIOS and IOIPSL on the ​ORCHIDEE wiki pages.