Linking Climate Model Pieces Together with a New and Improved “Coupler.”


The international Climate Model Intercomparison Project (CMIP5) has produced an enormous number of
climate and Earth system model simulations to help scientists understand climate change and variability. Performing those simulations and analyzing the data requires a great deal of sophisticated and high performance software, some of which is freely available to the community as open source. A recent issue of the journal Geoscientific Model Development was devoted to “Community Software to Support the Delivery of CMIP5.” Coupling software in an Earth system model, sometimes called ‘the coupler,’ is the software used to get the ocean, atmosphere, land surface, and sea ice models to talk to each other and simulate one system. Researchers at Argonne National Laboratory developed the Model Coupling Toolkit (MCT) used as the foundation coupling software in the U.S. Department of Energy/National Science Foundation-developed Community Earth System Model (CESM), one of the biggest contributers to CMIP5. This coupling software performs well on high-performance, massively parallel computers and is straightforward to integrate into a climate model, important “coupler” criteria. In addition to the CESM, five out of seven European-developed climate models contributing to CMIP5 used a coupler called OASIS whose developers recently announced a new version of their software that includes MCT.


Valcke, S., V. Balaji, A. Craig, C. DeLuca, R. Dunlap, R. W. Ford, R. Jacob, J. Larson, R.  O’Kuinghttons, G. D.
Riley, and M. Vertenstein. 2012. “Coupling Technologies for Earth System Modelling,” Geoscientific Model Development 5, 1589–96. DOI: 10.5194/gmd-5-1589-2012.