Technical Note: The Modular Earth Submodel System (MESSy) - a new approach towards Earth System Modeling P. Jöckel, R. Sander, A. Kerkweg, H. Tost, and J. Lelieveld Max-Planck-Institute for Chemistry, P.O. Box 3060, 55020 Mainz, Germany
Abstract. The development of a comprehensive Earth System Model (ESM) to
study the interactions between chemical,
physical, and biological processes, requires coupling of the different
domains (land, ocean, atmosphere, ...).
One strategy is to link existing domain-specific models with a universal
coupler, i.e. an independent standalone program organizing the
communication between other programs. In many cases, however, a
much simpler approach is more feasible.
We have developed the Modular Earth Submodel System (MESSy). It comprises
(1) a modular interface structure to connect to a , (2) an
extendable set of such for miscellaneous processes, and (3) a coding
MESSy is therefore not a coupler in the classical sense, but exchanges data
between a and several within one comprehensive executable. The
internal complexity of the is controllable in a transparent and user
friendly way. This provides remarkable new possibilities to study feedback
mechanisms (by two-way coupling).
Note that the MESSy and the coupler approach can be
combined. For instance, an atmospheric model implemented according to the
MESSy standard could easily be coupled to an ocean model by means of
an external coupler.
The vision is to ultimately form a comprehensive ESM which includes
a large set of submodels, and a base model which contains only a
central clock and runtime control. This can be reached stepwise,
since each process can be included independently. Starting from an existing
model, process submodels can be reimplemented according to
the MESSy standard. This procedure guarantees the availability of a
state-of-the-art model for scientific applications at any time of the
In principle, MESSy can be implemented into any kind of model,
either global or regional.
So far, the MESSy concept has been applied
to the general circulation model ECHAM5 and a number of process boxmodels.
Citation: Jöckel, P., Sander, R., Kerkweg, A., Tost, H., and Lelieveld, J.: Technical Note: The Modular Earth Submodel System (MESSy) - a new approach towards Earth System Modeling, Atmos. Chem. Phys., 5, 433-444, doi:10.5194/acp-5-433-2005, 2005.