Results of the second Ice Shelf-Ocean Model Intercomparison Project (ISOMIP+)
Yung, C. K., Asay-Davis, X. S., Adcroft, A., Bull, C. Y. S., Rydt, J. D., et al. (2026). Results of the second Ice Shelf-Ocean Model Intercomparison Project (ISOMIP+). The Cryosphere, doi:https://doi.org/10.5194/tc-20-2053-2026
| Title | Results of the second Ice Shelf-Ocean Model Intercomparison Project (ISOMIP+) |
|---|---|
| Genre | Article |
| Author(s) | C. K. Yung, X. S. Asay-Davis, A. Adcroft, C. Y. S. Bull, J. De Rydt, M. S. Dinniman, B. K. Galton-Fenzi, D. Goldberg, D. E. Gwyther, R. Hallberg, M. Harrison, T. Hattermann, D. M. Holland, D. Holland, P. R. Holland, J. Jordan, N. C. Jourdain, K. Kusahara, Gustavo M. Marques, P. Mathiot, D. Menemenlis, A. K. Morrison, Y. Nakayama, O. Sergienko, R. S. Smith, A. Stern, R. Timmermann, Q. Zhou |
| Abstract | Ocean-driven basal melting of Antarctic ice shelves plays an important role in the mass loss of the Antarctic Ice Sheet. Ice shelf cavity-resolving ocean models are a valuable tool for understanding ice shelf-ocean interactions and for simulating projections of ice shelf and ocean states under future climate. Designed to assess the current state of ice shelf–ocean modelling, the second Ice Shelf-Ocean Model Intercomparison Project, ISOMIP+, consists of 12 ocean model configurations submitted with a common, idealised experimental setup. Here, we focus on the experiments Ocean0-2 (Asay-Davis et al., 2016), which are ocean models with idealised, static ice shelf geometries, but where the ocean reaches a balance with prescribed far-field ocean conditions. Different thermal transfer coefficient values (ranging from 0.011 to 0.2) are used for each model in the melting parameterisation to achieve a common, tuned melt rate since the models cover a range of types of vertical coordinates, ice-ocean boundary layer treatments, and numerical schemes. These model differences lead to spread in the resultant ocean properties, circulation, boundary-layer structure and spatial distribution of melting. We also highlight similarities between models, such as a shared linear relationship across most models between melt rate and overturning and barotropic streamfunctions during the spin-up and spin-down, demonstrating a robust relationship between melt and circulation across models and forcing conditions. The ISOMIP+ results provide a systematic comparison of ice shelf cavity-capable ocean models. However, we also demonstrate the need for realistic ice shelf–ocean model intercomparison projects (some already underway) to assess model biases and inter-model variation against sparse observations. Further research is needed to understand the differences between models and further improve our modelled representations of the ice-ocean boundary layer and ice shelf cavity circulation. |
| Publication Title | The Cryosphere |
| Publication Date | Apr 13, 2026 |
| Publisher's Version of Record | https://doi.org/10.5194/tc-20-2053-2026 |
| OpenSky Citable URL | https://n2t.net/ark:/85065/d76w9gnp |
| OpenSky Listing | View on OpenSky |
| CGD Affiliations | OS |