Empirical research in DEM accuracy assessment has observed that DEM errors are correlated with terrain morphology, sampling density, and interpolation method. However, theoretical reasons for these correlations have not been accounted for. This paper introduces approximation theory adapted from computational science as a new framework to assess the accuracy of DEMs interpolated from topographic...

Based on the service specifications of the Open Geospatial Consortium (OGC), Spatial Data Infrastructures (SDI) support the visualization, access to vector and raster data or managing and search for spatial data. A standard for distributed spatial data processing was missing for a long time. This issue was addressed by the development of the OpenGIS Web Processing Service (WPS) specification. H...

Interferometric synthetic aperture radar (InSAR) has been developed as a powerful technique to derive high quality digital elevation models (DEMs) from a pair of SAR images. (Honikel, 1998) This paper describes InSAR processing principle, the crucial steps in deriving high quality DEMs from the C-band ERS Tandem Mission data, and addresses possible error sources before and during the processing...

[1] The Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud, and land Elevation Satellite (ICESat) provides a globally-distributed data set well suited for evaluating the vertical accuracy of Shuttle Radar Topography Mission (SRTM) digital elevation models (DEMs). The horizontal error (2.4 ± 7.3 m) and vertical error (0.04 ± 0.13 m per degree of incidence angle) for the ICESat data used ...

[1] An effective and widely used method for removing spurious pits in digital elevation models consists of filling them until they overflow. However, this method sometimes creates large flat regions which in turn pose a problem for the determination of accurate flow directions. In this study, we propose to suppress each pit by creating a descending path from it to the nearest point having a low...

Glaciers are indicators of the global climate change. The change in the extent and volume of a glacier can be estimated from digital elevation models (DEMs) produced from remotely sensed spaceborne or airborne data using photogrammetric, interferometric, or laser scanning techniques. For this study, the most promising data sources available were selected and tested. The selected sites were two ...

Introduction: Ray-tracing (RT) of Lunar Digital Elevation Models (DEM)'s is performed to virtually derive the degree of radiation incident to terrain as a function of time, orbital and ephemeris constraints [1-4]. This process is an integral modeling process in lunar polar research and exploration due to the present paucity of terrain information at the poles and mission planning activities for...

The high-resolution satellite imageries (HRSI) are as primary dataset for different applications such as DEM generation, 3D city mapping, change detection, monitoring, and deformation detection. The geo-location information of HRSI are stored in metadata called Rational Polynomial Coefficients (RPCs). There are many methods to improve and modify the RPCs in order to have a precise mapping. In t...

This paper describes a new fast and scalable parallel algorithm to compute global flow accumulation for automatic drainage network extraction in large digital elevation models (DEM for short). Our method uses the D8 model to compute the flow directions for all pixels in the DEM (except NODATA and oceans). A parallel spanning tree algorithm is proposed to compute hierarchical catchment basins to...

The ERS Tandem Mission from August 1995 to May 1996 provided a large resource of data that can be used for a number of applications in the geosciences, based on the principle of interferometry, referred to in this paper as InSAR. InSAR techniques can provide a new and efficient method of deriving DEMs with little manual input. This paper describes research on the determination of digital elevat...