CSDMS 2024: Coastlines, Critical Zones and Cascading Hazards: Modeling Dynamic Interfaces from Deep Time to Human Time

On the Practical Importance of Theory in Landscape Evolution Models

Amilcare Porporato

Princeton University, United States

Landscape evolution involves manifold processes from different disciplines, including geology, geomorphology and ecohydrology, often interacting nonlinearly at different space-time scales. While this gives rise to fascinating patterns of interconnected networks of ridges and valleys, it also challenges Landscape Evolution Models (LEMs), which typically rely on long-term numerical simulations and mostly have only current topographies for comparison. While adding process complexity (and presumably realism) is certainly useful to overcome some of these challenges, is also exacerbates issues related to proper calibration and simulation. This talk advocates more focus on the theoretical analysis of LEMs to alleviate some of these issues. By focusing on the essential elements that distinguish landscape evolution, the resulting minimalist LEMs become more amenable to dimensional analysis and other methods of nonlinear field equations, used for example in fluid mechanics and turbulence, offering fertile ground to sharpen model formulation (i.e., the stream-power erosion term), unveil distinct dynamic regimes (e.g., unchannelized, from incipient valley formation, transitional and statistically self-similar fractal regime), and properly formulate questions related to the existence of steady state solution (as opposed to a situation of space time chaos, similar to a geomorphological turbulence). We also discuss benchmarks for evaluating numerical simulation and novel avenues for numerical methods, as well as ways to bridge between spatially discrete models (i.e., river networks) and continuous, partial-differential-equation models.

Please acknowledge the original contributors when you are using this material. If there are any copyright issues, please let us know ( and we will respond as soon as possible.

Of interest for:
  • Terrestrial Working Group
  • Coastal Working Group
  • Education and Knowledge Transfer (EKT) Working Group
  • Cyberinformatics and Numerics Working Group
  • Hydrology Focus Research Group
  • Chesapeake Focus Research Group
  • Critical Zone Focus Research Group
  • Human Dimensions Focus Research Group
  • Geodynamics Focus Research Group
  • Ecosystem Dynamics Focus Research Group
  • Coastal Vulnerability Initiative
  • Continental Margin Initiative
  • Artificial Intelligence & Machine Learning Initiative
  • River Network Modeling Initiative