Accuracy Assessment of Digital Terrain Model Dataset Sources for Hydrogeomorphological Modelling in Small Mediterranean Catchments

• DOI: 10.3390/rs10122014
• Publication Date: 2018-12-12T15:54:26Z
• Authors: Lukas Graf; Mariano Moreno-de...; Maurici Ruiz; Aleix Calsamiglia; Julián García-Com...; Josep Fortesa; José A. López-Tar...; Joan Estrany
• Keywords: Ground truth

Digital terrain models (DTMs) are a fundamental source of information in Earth sciences. DTM-based studies, however, can contain remarkable biases if limitations and inaccuracies these disregarded. In this work, four freely available datasets, including Shuttle Radar Topography Mission C-Band Synthetic Aperture (SRTM C-SAR V3 DEM), Advanced Spaceborne Thermal Emission Reflection Radiometer Global Elevation Map (ASTER GDEM V2), two nationwide airborne light detection ranging (LiDAR)-derived DTMs (at 5-m 1-m spatial resolution, respectively) were analysed three geomorphologically contrasting, small (3–5 km2) catchments located Mediterranean landscapes under intensive human influence (Mallorca Island, Spain). Vertical accuracy as well the each dataset’s characteristics on hydrological geomorphological modelling applicability assessed by using ground-truth data, classic geometric morphometric parameters, recently proposed index sediment connectivity. Overall vertical accuracy—expressed root mean squared error (RMSE) normalised median deviation (NMAD)—revealed highest for (RMSE = 1.55 m; NMAD 0.44 m) LiDAR 1.73 0.84 m). SRTM data was lower 6.98 5.27 m), but considerably higher than ASTER 16.10 11.23 All datasets affected systematic distortions. Propagation errors coarse horizontal resolution caused negative impacts flow routing, stream network, catchment delineation, to extent, distribution slope values. These should be carefully considered when applying hydrogeomorphological modelling.