Software tools for landscape evolution modeling

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Fastscape is a set of open-source software components aimed at making landscape evolution models and topographic analysis algorithms readily accessible to a wide range of users, from experts in landscape evolution modelling to scientists, researchers and teachers in the broader Earth science community.


Fastscape is a flexible and modular landscape evolution model that is highly connected to the Python scientific ecosystem, thanks to the Xarray-simlab modeling framework (see below).

It provides +30 components that can be combined together in order to create custom models. Users can also plug in their own components.

Its high-level, user-friendly interface enables interactive landscape evolution modeling, e.g., within Jupyter notebooks.

Try it online! Documentation Source repository

Fastscapelib (Fortran)

Fastscapelib-Fortran implements efficient algorithms for landscape evolution modeling.

It provides a basic Fortran interface with model setup, runtime and I/O routines that can be used in standalone programs or for coupling landscape evolution models with other Fortran codes (e.g., tectonic or climate models).

It may also be built as a Python extension with a NumPy-compatible, low-level API. It is currently used as a core backend library in "Fastscape".

Documentation Source repository

Fastscapelib (C++)

Fastscapelib (C++) is the successor of Fastscapelib-Fortran (it is still in early development).

It aims to provide a flexible, yet optimized system for implementing various core algorithms (e.g., flow routing and enforcement, solvers for erosion processes) on multiple grids.

It exposes a C++ API that is compatible with the Xtensor library (i.e., a multi-dimensional array library heavily inspired by NumPy). Thanks to Xtensor, it also exposes a Python/NumPy API and may have language bindings for R and Julia.

Documentation Source repository


Xarray-simlab is a modeling framework used by "Fastscape" to build, setup and run custom models.

It is very well integrated with tools of the Python Scientific / PyData / Pangeo ecosystems such as Xarray, Dask, Zarr and the Holoviz projects.

It is a generic framework that can be used to build models in a wide range of domains.

Documentation Source repository


Ipyfastscape provides interactive widgets for topographic data analysis and modelling in Jupyter notebooks.

While ipyfastscape is tightly integrated with fastscape, it also integrates very well with any data in the form of an xarray dataset or any model created with xarray-simlab.

Ipyfastscape's high-level UI components can be reused for building interactive web applications (dashboards). It's very useful for research communication, teaching and outreach.

Try it online! Source repository


  • J. Braun, and S.D. Willett, 2013. A very efficient, O(n), implicit and parallel method to solve the basic stream power law equation governing fluvial incision and landscape evolution. Geomorphology, 180-181, pp., 170-179.
  • G. Cordonnier, B. Bovy and J. Braun, 2019. A versatile, linear complexity algorithm for flow routing in topographies with depressions. Earth Surf. Dynam., 7, pp. 549–562.
  • X. Yuan, J. Braun, L. Guerit, D. Rouby and G. Cordonnier, 2019. A New Efficient Method to Solve the Stream Power Law Model Taking Into Account Sediment Deposition. Journal of Geohysical Research - Surface, 124 (6), pp. 1346-1365.
  • X. Yuan, J. Braun, L. Guerit, B. Simon, B. Bovy, D. Rouby, C. Robin and R. Jiao, 2019. Linking continental deposition to marine sediment transport and deposition: a new implicit and O(n) method for inverse analysis. Earth and Planetary Science Letters, 524, 115728.

Some other tools

A few other, publicly available tools for topographic analysis and landscape evolution modeling: