🌊 Thetis

Thetis is an open-source, finite element framework for simulating coastal and estuarine flows with advanced numerics, high flexibility, and easy extensibility.

Thetis builds on the Firedrake finite element library to provide robust solvers for 2D/3D shallow water equations and related physical processes in the coastal ocean.

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🌟 Key Features

✅ 2D depth-averaged and 3D baroclinic shallow water solvers
✅ Wetting and drying schemes for realistic coastlines
✅ Scalar transport (salinity, temperature, tracers)
✅ Adjoint capabilities for data assimilation and inverse modeling
✅ Flexible unstructured meshes
✅ Open-source and easily extensible Python codebase

📚 Full documentation and installation instructions are available at thetisproject.org

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🚀 Installation

Please see the installation instructions on the website for full details.

For the release branch:

1. Install Firedrake and activate its virtual environment.
2. Install Thetis within the Firedrake environment:

pip install git+https://github.com/thetisproject/thetis.git

You can instead install and switch between different versions of Thetis with:

git clone https://github.com/thetisproject/thetis
cd thetis
git checkout <branch_name>
pip install -e .

Note The latest development branch of Thetis (main) will require the corresponding main branch of Firedrake. See the website for more details.

Release branch weekly status

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Getting Started

To get up and running with Thetis once it has been installed, we recommend checking out the basic tutorials and documentation. Further examples can then be found in the repository at examples. See examples/README.md for detailed descriptions of each example script.

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📬 Questions?

Check the website for ways of reaching out to developers!

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Citing Thetis

If Thetis is helpful in your research, please cite:

Kärnä, T., Kramer, S. C., Mitchell, L., Ham, D. A., Piggott, M. D. & Baptista, A. M. (2018).
Thetis coastal ocean model: discontinuous Galerkin discretization for the three-dimensional hydrostatic equations.
Geoscientific Model Development, 11: 4359–4382.
doi: 10.5194/gmd-11-4359-2018

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License

Thetis is available under the MIT License. See the LICENSE file for details.