Articles | Volume 19, issue 16
https://doi.org/10.5194/gmd-19-7687-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-19-7687-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Code accessibility and code quality across phases of the models of the Coupled Model Intercomparison Project
Michael García-Rodríguez
CORRESPONDING AUTHOR
EPhysLab, CIM-UVigo, Universidade de Vigo, 32004, Ourense, Spain
School of Computer Sciences, Universidade de Vigo, 32004, Ourense, Galicia, Spain
Javier Rodeiro-Iglesias
School of Computer Sciences, Universidade de Vigo, 32004, Ourense, Galicia, Spain
EPhysLab, CIM-UVigo, Universidade de Vigo, 32004, Ourense, Spain
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Editorial statement
The Climate Modelling Intercomparison Project coordinates climate projections made by the world's flagship climate models which feed into reports such as the IPCC. It should remain a concern that even in the 6th version of the project, relatively few of the models have made their code accessible to other scientists, let alone the general public. Furthermore, the consideration of what may or may not constitute good code is of interest to all those involved in geoscientifc model development. This paper may come at an interesting point in time. Since their inception in the 1960s, prognostic climate models have always used fortran and similar languages to create algorithms which directly reproduce our basic geoscientific understanding of how the climate evolves, through differential equations. The authors propose that things may be evolving in a new direction, with the potential incorporation of machine learning and other forms of AI into future generations of the models. This will surely present new challenges to the concept and assessment of scientific reproducibility and code development.
The Climate Modelling Intercomparison Project coordinates climate projections made by the...
Short summary
We studied how accessible and reliable the computer code behind major climate models has been over time. By reviewing different phases of the Coupled Model Intercomparison Project, we found improvements in transparency and coding practices, but also gaps that limit reproducibility. Our work suggests practical steps to make future climate research more open, traceable, and trustworthy for scientists and society.
We studied how accessible and reliable the computer code behind major climate models has been...