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

Using Fill-Spill-Merge to understand and analyze landscape depressions

Kerry Callaghan

University of Illinois Chicago, United States

Fill-Spill-Merge (FSM) is an algorithm that distributes runoff on a landscape to fill or partially fill depressions. When a depression fills, excess water can overflow into neighbouring depressions or the ocean. In this clinic, we will use FSM to assess changes in a landscape’s hydrology when depressions in a DEM are partially or fully filled with water. We will discuss why it may be important to consider depressions more closely than just with removal. I will describe the design of the FSM algorithm, and then we will use FSM on a DEM to look at how landscape hydrology changes under different hydrologic conditions. This clinic may be helpful to those interested in topics such as landscape hydrology, landscape evolution, flow routing, hydrologic connectivity, and lake water storage.

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Of interest for:
  • Terrestrial Working Group
  • Cyberinformatics and Numerics Working Group
  • Hydrology Focus Research Group
  • Critical Zone Focus Research Group
  • Ecosystem Dynamics Focus Research Group
  • River Network Modeling Initiative