Coupling of the Ice-sheet and Sea-level System Model (version 4.24) with hydrology model CUAS-MPI (version 0.1) using the preCICE coupling library

Kurzfassung

Accurate earth system models must include interactions between atmosphere, ocean, and continental ice sheets. To build such models, numerical solvers that compute the evolution of the different components are coupled. There are frameworks and libraries for coupling that handle the complex tasks of coordinating the solver execution, communicating between processes, and mapping between different meshes. This allows solvers to be developed independently without compromises on numerical methods or technology. Code reuse is improved, both over large, monolithic software systems that reimplement each coupled model as well as over ad-hoc coupling scripts. In this work, we use the preCICE coupling library to couple the Ice-sheet and Sea-level System Model (ISSM) with the subglacial hydrology model CUAS-MPI. An adapter for each model is required that passes the meshes and coupled variables between the model and preCICE. We describe the generic, reusable adapters we developed for both models and demonstrate their features experimentally. We also include computational performance results for the coupled system on a high-performance computing cluster. Coupling with preCICE has low computational overhead and does not negatively impact scaling. Therefore, the presented software facilitates studies of the subglacial hydrology systems of continental ice sheets as well as coupling ISSM or CUAS-MPI with other codes such as in global earth system models.