Paper Info
Title
Estimating Flow Distribution over Digital Elevation Models Using a Form-Based Algorithm
Abstract
This paper discusses a new approach to estimate flow distribution over a continuous surface. This approach is based on the analysis of topographic form of a surface facet that dictates the flow distribution. In the case of a raster Digital Elevation Model (DEM), the facet consists of a centre cell and its eight neighbouring cells. If the form of the facet is convex, the water flow is divergent; thus the amount of flow is distributed to all cells that have a lower elevation. In the case of a concave or flat surface, the convergent flow is directed to the main drainage direction. Comparison between the results of this algorithm with the traditional 'eight-move' algorithm, which is widely used in today's commercial GIS software, indicated that the form-based algorithm yielded a more realistic results in estimating flow accumulation over the land surface, but produced less convincing results in deriving a drainage network. INTRODUCTION AND BACKGROUND Catchment topography is critical for models of distributed hydrological processes. Slope controls flow pathways for surface as well as near surface flow, and influences the sub surface flow pattern substantially. The key parameter in catchment topography is flow distribution, which tell us how overland flow is distributed over the catchment area. Stating flow distribution over a land surface is a crucial measurement in hydrological modelling, the use of Digital Elevation Models (DEM) has made it possible to estimate flow on each location over a surface. Based on the flow distribution estimation on each location represented by a DEM, the drainage pattern over an area, as well as various hydrological parameters, such as catchment area and up-stream flow accumulation, can be modelled. One common approach for measuring flow distribution is the hydrological flow modelling methods that are widely applied to geomorphological and hydrological problems (6). This method is based on the following basic principles:
Year
DOI
Venue
1998
10.1080/10824009809480502
Annals of GIS
Keywords
Field
DocType
overland flow,digital elevation model,stream flow,hydrological modelling,control flow
Geographic information system,Raster graphics,Water flow,Topographic map,Flow (psychology),Algorithm,Digital elevation model,Facet (geometry),Elevation,Geography
Journal
Volume
Issue
Citations 
4
1&2
6
PageRank 
References 
Authors
2.20
1
3
Name
Order
Citations
PageRank
Petter Pilesjö1206.38
Qiming Zhou29720.48
Lars Harrie36813.37