Evaluating the Effects of DEM Properties on the Spatial and Statistical Distribution of Hydrological Surface Attributes
Incorporating topographic detail within advanced hydrological models has been achieved using digital elevation models (DEMs). Although DEMs prove useful for a number of hydrological applications, they are often the end result of numerous processing steps that contain some amount of uncertainty. These uncertainties greatly influence DEM quality and can further propagate to DEM-derived attributes. This research examines the impacts of DEM grid resolution, elevation source data, and conditioning techniques on the spatial and statistical distribution of field-scale hydrological attributes. Variation in DEM grid resolution and elevation source data resulted in significant differences in the spatial and statistical distributions of variables. The resulting effects of applied conditioning techniques were closely linked to DEM grid resolution; differences in derived attributes among conditioning techniques significantly increased with grid resolution. Greater consideration of DEM conditioning is therefore required at finer-resolutions.