Water Resources Research · 2006 · 154 citations · 47 references
ComputingEarth SciencesHydrologyDigital Elevation ModelingHydrologic ModelingTerrain AnalysisDigital Elevation ModelsDigital Terrain ModelingDigital Terrain ModelsDistributed Hydrologic ModelingTerrain ModelingTopographic AnalysisDem Accuracy AssessmentDigital Elevation Model ProcessingDivergenceGlobal Positioning SystemGrid Cell SizeGrid-based Terrain ModelsSlopesUpslope Area Analysis
Terrain attributes based on upslope contributing area, A , are used widely in distributed hydrologic models. Several grid‐based algorithms are available for estimating A . In this study, five algorithms (D8, ρ 8, MFD, DEMON, and D∞) were compared quantitatively on two undulating agricultural fields (63 and 109 ha) in northeastern Colorado. Global positioning system (GPS) data (0.02‐m accuracy) were used to generate grid digital elevation models (DEMs) at 5‐, 10‐, and 30‐m cell sizes. Relative differences between A values estimated using single‐ and multiple‐direction algorithms increased with decreasing grid cell size. Relative differences were greatest along ridges and side slopes, and differences decreased where the terrain became more convergent. Multiple‐direction algorithms (MFD, DEMON, and D∞), allowing for flow divergence, are recommended on these undulating terrains for 5‐ and 10‐m grids where A is most sensitive to the algorithm selection.
47