7. Flow modeling
7.A Flow routing, watershed analysis
Outline:- cumulative terrain parameters based on flow tracing: definitions and general approach (flow path length, flow accumulation, stream networks, watershed boundaries, ridge lines)
- methods for computing flow direction (D8, Dinf), flow tracing (SFD, MFD, uniform, weighted)
- methods for flow tracing through depressions and flat areas (filling, carving, hybrid, least cost path)
- principle of stream extraction from a DEM and watershed delineation
Lecture
Lecture slides: Flow routing and watershed analysis
Supplemental materials:
- Surface Water Flow Modeling chapter from Petrasova et al., 2018, Tangible Modeling with Open Source GIS. Second Edition. Springer. Available free through NCSU library. or through Springer
- Metz, M. et al. (2011) Efficient extraction of drainage networks from massive, radar-based elevation models with least cost path search, Hydrology and Earth System Sciences 15, pp. 667-678.
- J Jasiewicz, M Metz, 2011: A new GRASS GIS toolkit for Hortonian analysis of drainage networks, Computers and Geosciences.https://doi.org/10.1016/j.cageo.2011.03.003
- Nobre et al. 2011, Height Above the Nearest Drainage – a hydrologically relevant new terrain model, Journal of Hydrology,404(1-2), p. 13-29.
- Original lecture:Slides, videos: Flow accumulation, Stream extraction and watersheds
Assignment A
- Approach: (New) Jupyter Notebook, GRASS solution, ArcGIS Pro solution
7.B Hydrologic and Erosion modeling
Outline:- geospatial aspects of models: spatially averaged and distributed models
- spatial hydrologic modeling
- spatial modeling of erosion and sediment transport
- deriving input parameters, analysis and visualization of modeling results
- modeling impact of landuse change
Lecture
Lecture slides: Hydrologic and Erosion Modeling,
Supplemental materials:
- Surface Water Flow Modeling and Soil Erosion Modeling chapters from Petrasova et al., 2018, Tangible Modeling with Open Source GIS. Second Edition. Springer. Available free through NCSU library. or through Springer
- Mitasova et al., 2013, GIS-based soil erosion modeling, In: Treatise on Geomorphology. Academic Press, San Diego, CA, vol. 3, Remote Sensing and GIScience in Geomorphology, pp. 228–258
- Soil erosion and deposition modeling tutorial (material under development)
- Erosion modeling tutorial (old but useful document)
- Original lectures: Slides I: Geospatial modeling and hydrology, Slides II: Erosion modeling, videos: Geospatial Modeling, Hydrologic Modeling, Erosion Modeling, Erosion Modeling applications.
Assignment B:
- Brief theoretical background (equations used to write map algebra expressions)
- Approach: (New) Jupyter Notebook, GRASS solution, ArcGIS Pro solution
- Optional: process based hydrologic modeling using path sampling method (SIMWE)