Integrating numerical models and terrain analysis in TopoToolbox

Many numerical models depend critically on digital elevation models (DEM). Hydrodynamic models, landslide susceptibility models, or glacial models, for example, require DEMs as input. The quality of the DEMs and DEM preprocessing are thus vital for many models. Hydrodynamic simulations are highly sensitive to DEM errors and artefacts, while other models require smoothing to ensure numerical stability. Model outputs are likewise strongly controlled by topography: flood extents depend on topographic gradients and surface elevations relative to river channels, glacier extent is constrained by topographic height and confinement, and geomorphic models generate time-varying DEMs that document topographic changes over time. These close links suggest that model preparation, execution, and analysis should be conducted within a unified terrain-analysis environment.

TopoToolbox is a terrain analysis framework originally developed in MATLAB and now available in Python and R. We demonstrate how simulation software can be integrated into TopoToolbox by various means including via the C API of libtopotoolbox or higher level interfaces provided by the language-specific implementations of TopoToolbox. Interfacing with TopoToolbox enables seamless DEM preprocessing alongside visualization and analysis of model outputs. Working within a single, specialized environment simplifies workflows, improves reproducibility, and enhances the usability and dissemination of modeling software.