A model system is a set of different models
sharing the same infrastructure.
Example: ECHAM5/MESSy including the box-models
A model is represented by one executable.
Examples: ECHAM5/MESSy (echam5.exe),
the MECCA box-model
A submodel is the implementation of one process according to the
MESSy coding standard, i.e., split into the submodel core layer (SMCL)
Fortran 90 module(s) and the submodel interface layer (SMIL) Fortran 90
A box-model represents one process in its smallest meaningful entity
(e.g. box (0-D), or vertical column (1-D)) as a stand-alone executable.
A set of files representing a model
or model system, usually
archived as zip- or tar-file.
The model version is indicated by the version-number(s)
of the model distribution;
and is also contained in the code and output to log-file(s).
The submodel version is indicated by the version number in the
submodel core layer (SMCL) file of the submodel.
- The model version is only valid for code
without modifications! In other cases it is a
- In the case of a model system, each
component may have its individual version number.
Example: CHARACTER(LEN=*), PARAMETER :: modver = '1.1.3b'
The model configuration is the scope of model characteristics selected
at configuration-time or at compile-time, which cannot be changed
during run-time, but which do not require manual code changes.
The model setup is the scope of model characteristics determined at run-time.
- automatic code generation, e.g.,
MECCA, SCAV mechanisms (including intermediate code
processing (e.g., for vectorisation or de-indexing))
- architecture / compiler selection
- preprocessor options, e.g,
- parallel (MPI) or single CPU executable
- ECHAM5 with MESSy or without
- compiler options (e.g., error checks, degree of optimisation)
- horizontal / vertical resolution (determined by
- upper (mid-) boundary (e.g., middle atmosphere (MA)),
(determined by namelist switch)
- parameters and switches in ECHAM5 namelists
- initial and boundary conditions (e.g., AMIPII-SST,
- selection of active submodels (ON/OFF)
- coupling between submodels, and submodels and basemodel
- initial and boundary conditions (including emissions !)
- parameters and switches in submodel namelists
This page was last modified on
15 May 2007.
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