Subscription or Fee Access
Quality Assessment of Contour Interpolated Digital Elevation Models in a Diverse Topography
The present paper address the combined effect of choice of interpolation techniques and grid cell size on DEM quality. Five interpolators namely triangulation with linear interpolation, inverse distance weighing, thin plate spline, ordinary kriging and Topogrid were used to generate DEMs of 30m, 45m, 60m, 75m and 90m resolutions. The relative DEM accuracy were evaluated using elevation accuracy, comparison of derived geomorphic feature, interpolation artifact and spatial variability for three different terrain complexity classes. Results of vertical accuracy showed that there were little variation in RMSE value of different interpolators except Topogrid and effect of cell size was not pronounced in nature. Comparisons of derived basin boundary and stream network with reference one showed a high level of disparity among the interpolators with moderate level of scale dependency. Sink analysis revealed that the different interpolation methods produced DEMs with different level of artifacts. Spatial variability measurement based on semivariogram modeling and entropy indicated a significant difference in spatial information content of interpolated DEMs with changing cell size. Results also showed that Top grid is superior for hydrologic analysis of the basin. But, decreased DEM quality with increasing terrain complexity urge that the accuracy of DEM generated using a particular interpolator and cell size is highly site specific.
DEM accuracy, interpolation method, cell size, sink, spatial variability
Disclaimer/Regarding indexing issue:
We have provided the online access of all issues and papers to the indexing agencies (as given on journal web site). It’s depend on indexing agencies when, how and what manner they can index or not. Hence, we like to inform that on the basis of earlier indexing, we can’t predict the today or future indexing policy of third party (i.e. indexing agencies) as they have right to discontinue any journal at any time without prior information to the journal. So, please neither sends any question nor expects any answer from us on the behalf of third party i.e. indexing agencies.Hence, we will not issue any certificate or letter for indexing issue. Our role is just to provide the online access to them. So we do properly this and one can visit indexing agencies website to get the authentic information.