NCSU GIS/MEA582:
Geospatial Modeling and Analysis

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

Assignment A

7.B Modeling Geospatial Processes: Hydrologic and Erosion modeling

Outline:
  • spatially explicit modeling: principles and applications, role of GIS
  • geospatial aspects of models: spatially averaged and distributed models
  • general approaches and methods: empirical and physics based components of models
  • steady state, continuous time and dynamic models and related modeling tools
  • spatial hydrologic modeling: processes and methods
  • spatial modeling of erosion, sediment transport and landscape evolution
  • deriving input parameters, analysis and visualization of modeling results
  • simulating impact of landuse and climate change

Lecture

Supplemental materials:

Assignment B:

Homework 7 A and B:

Prepare a paper where you compare different methods for flowrouting and watershed analysis, compute flooded area, and explain and discuss impact of model parameters and land use scenarios on spatial pattern and magnitude of erosion as simulated by simple GIS-based models.