Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 11 4 2007 10.5194/hess-11-1243-2007 http://www.hydrol-earth-syst-sci.net/11/1243/2007/ http://www.hydrol-earth-syst-sci.net/11/1243/2007/hess-11-1243-2007.html http://www.hydrol-earth-syst-sci.net/11/1243/2007/hess-11-1243-2007.pdf 1243 1247 2007-05-03 Technical Note: Water flow routing on irregular meshes D. Bänninger dominik.baenninger@unibas.ch Institute of Environmental Geosciences, University of Basel, Bernoullistrasse 30, 4056 Basel, Switzerland For spatially explicit hydrological modelling an algorithm was required that works as a cellular automata on irregular meshes. From literature it was found that the usual algorithms applied for this purpose do not route the water flow correctly between adjacent cells. In this study the hydraulic linking between mesh cells is done by calculating the flow cross section between the mesh cells. The flow cross sections are positioned in the centre of the mesh edges and are perpendicular to the local gradient of the digital elevation model. The presented algorithm is simple in its implementation and efficient in computation. It is shown that the proposed algorithm works correctly for different synthesised hill slope shapes. Braun, J. and Sambridge, M.: Modelling landscape evolution on geological time scales: A new method based on irregular spatial discretization, Basin Research, 9, 27–52, 1997. Costa-Cabral, M. and Burges, S.: Digital elevation model networks (DEMON): A model of flow over hillslopes for computation of contributing and dispersal areas, Water Resour. Res., 30, 1681–1692, 1994. Delaunay, B.: Sur la sphere vide, Bulletion of Academy of Sciences of the USSR, pp 793–800, 1934. Fairfield, J. and Leymarie, P.: Drainage networks from grid digital elevation models, Water Resour. Res., 27, 709–717, 1991. Freeman, T.: Calculating catchment area with divergent flow based on a regular grid, Comput. Geosci., 17, 413–422, 1991. Gandoy-Bernasconi, W. and Palacios-Velez, O.: Automatic cascade numbering of unit elements in distributed hydrological models, J. Hydrol., 112, 375–393, 1990. Grayson, R. and Blöschl, G.: Spatial Patterns in Catchment Hydrology, Cambridge University Press, 2000. Ivanov, V., Vivoni, E., Bras, R., and Entekhabi, D.: Catchment hydrologic response with a fully distributed triangulated irregular network model, Water Resour. Res., 40, w11102, doi:10.1029/2004WR003218, 2004. Lea, N.: Overland Flow: Hydraulics and Erosion Mechanics, in: An aspect driven kinematic routing algorithm, edited by: A. Parsons and A. Abrahams, 1992. Lee, J.: Comparison of existing methods for building triangular irregular network models of terrain from grid digital elevation models, International Journal of Geographical Information Systems, 5, 267–285, 1991. O'Callaghan, J. and Mark, D.: The extraction of drainage networks from digital elevation data, Computer Vision Graphics Image Processes, 28, 328–344, 1984. Palacios-Velez, O. and Cuevas-Renaud, B.: Automated river-course, ridge and basin delineation from digital elevation data, J. Hydrol., 86, 299–314, 1986. Palacios-Velez, O., Gandoy-Bernasconi, W., and Cuevas-Renaud, B.: Geometric analysis of surface runoff and the computation order of unit elements in distributed hydrological models, J. Hydrol., 211, 266–274, 1998. Quinn, P., Beven, K., Chevallier, P., and Plachon, O.: The prediction of hillslope flow paths for distributed hydrological modeling using digital terrain models, Hydrol. Processes, 5, 59–80, 1991. Shewchuk, J R.: Triangle: Engineering a 2D Quality Mesh Generator and Delaunay Triangulator, in: Applied Computational Geometry: Towards Geometric Engineering, edited by: Lin, M C. and Manocha, D., Vol 1148 of Lecture Notes in Computer Science, Springer-Verlag, from the First ACM Workshop on Applied Computational Geometry, pp 203–222, 1996. Tarboton, D.: A new method for the determination of flow directions and upslope areas in grid digital elevation models, Water Resour. Res., 33, 309–319, 1997. Tucker, G., Lancaster, S., Gasparini, N., Bras, R., and Rybarczyk, S.: An object-oriented framework for distributed hydrologic and geomorphologic modeling using triangulated irregular networks, Computer and Geosciencies, 27, 959–973, 2001. Vivoni, E., Ivanov, V., Bras, R., and Entekhabi, D.: On the effects of triangulated terrain resolution on distributed hydrologic model response, Hydrol. Processes, 19, 2101–2122, 2005. Wigmosta, M., Vail, L., and Lettenmaier, D.: A distributed hydrology-vegetation model for complex terrain, Water Resour. Res., 30, 1665–1679, 1994.