The EGU interactive community platform
The EGU interactive community platform
EGUsphere
Preprints
Preprints
https://doi.org/10.5194/egusphere-2024-3493
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/egusphere-2024-3493
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
Preprints
28 Nov 2024
 | 28 Nov 2024
Status: this preprint is open for discussion.

A case for open communication of bugs in climate models, made with ICON version 2024.01

Ulrike Proske, Nils Brüggemann, Jan P. Gärtner, Oliver Gutjahr, Helmuth Haak, Dian Putrasahan, and Karl-Hermann Wieners

Abstract. Climate models are not just numerical representations of scientific knowledge, they are also human-written software programs. As such, they contain coding mistakes, which may look mundane, but can affect the results of interconnected and complex models in unforeseen ways. These bugs are underacknowledged in the climate science community.

We describe a sea ice bug in the coupled atmosphere-ocean-sea ice model ICON and its history. The bug was caused by a logical flag that was set incorrectly, such that the ocean did not experience friction from sea ice and thus the surface velocity did not slow down, especially in the presence of ocean eddies. While describing the bug and its effects, we also give an example of visual and concise bug communication. In addition, we conceptualize this bug as representing a novel species of resolution-dependent bugs. These are long-standing bugs that are discovered during the transition to high-resolution climate models due to features that are resolved at the kilometer scale. This case study serves to illustrate the value of open documentation of bugs in climate models and to encourage our community to adopt a similar approach.

How to cite. Proske, U., Brüggemann, N., Gärtner, J. P., Gutjahr, O., Haak, H., Putrasahan, D., and Wieners, K.-H.: A case for open communication of bugs in climate models, made with ICON version 2024.01, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-3493, 2024.
Received: 08 Nov 2024 – Discussion started: 28 Nov 2024
Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Ulrike Proske, Nils Brüggemann, Jan P. Gärtner, Oliver Gutjahr, Helmuth Haak, Dian Putrasahan, and Karl-Hermann Wieners

Status: open (until 23 Jan 2025)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
Post a comment Subscribe to comment alert
Ulrike Proske, Nils Brüggemann, Jan P. Gärtner, Oliver Gutjahr, Helmuth Haak, Dian Putrasahan, and Karl-Hermann Wieners

Data sets

Data and scripts for the publication "A case for open communication of bugs in climate models" Ulrike Proske et al. https://doi.org/10.5281/zenodo.14220611

Model code and software

ICON release 2024.01 The ICON partnership (DWD, MPI-M, DKRZ, KIT, C2SM) https://doi.org/10.35089/WDCC/IconRelease01

Ulrike Proske, Nils Brüggemann, Jan P. Gärtner, Oliver Gutjahr, Helmuth Haak, Dian Putrasahan, and Karl-Hermann Wieners
Metrics will be available soon.
Latest update: 28 Nov 2024
Download
Short summary
Climate models contain coding mistakes, which may look mundane, but can affect the results of interconnected and complex models in unforeseen ways. We describe a sea ice bug in the coupled atmosphere-ocean-sea ice model ICON, giving an example of visual and concise bug communication. This bug represents a novel species of resolution-dependent bugs. The case illustrates the value of open documentation of bugs in climate models and to encourage our community to adopt a similar approach.
Read more