title: Evaluation of different digital elevation models for analyzing drainage morphometric parameters in a mountainous terrain: a case study of the Supin-Upper Tons Basin, Indian Himalayas.
abstract: BACKGROUND
  With myriad geospatial datasets now available for terrain information extraction and particularly streamline demarcation, there arises questions regarding the scale, accuracy and sensitivity of the initial dataset from which these aspects are derived, as they influence all other parameters computed subsequently. In this study, digital elevation models (DEM) derived from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER V2), Shuttle Radar Topography Mission (SRTM V4, C-Band, 3 arc-second), Cartosat -1 (CartoDEM 1.0) and topographical maps (R.F. 1:250,000 and 1:50,000), have been used to individually extract and analyze the relief, surface, size, shape and texture properties of a mountainous drainage basin.
  
  
  RESULTS
  Nestled inside a mountainous setting, the basin is a semi-elongated one with high relief ratio (>90), steep slopes (25°-30°) and high drainage density (>3.5 km/sq km), as computed from the different DEMs. The basin terrain and stream network is extracted from each DEM, whose morphometric attributes are compared with the surveyed stream networks present in the topographical maps, with resampling of finer DEM datasets to coarser resolutions, to reduce scale-implications during the delineation process. Ground truth verifications for altitudinal accuracy have also been done by a GPS survey.
  
  
  CONCLUSIONS
  DEMs derived from the 1:50,000 topographical map and ASTER GDEM V2 data are found to be more accurate and consistent in terms of absolute accuracy, than the other generated or available DEM data products, on basis of the morphometric parameters extracted from each. They also exhibit a certain degree of proximity to the surveyed topographical map.
authors.affiliation: Department of Geography, Bhairab Ganguly College, 2, Feeder Road, Belghoria, Kolkata, West Bengal 700056 India.
authors.forename: Sayantan
authors.initials: S
authors.lastname: Das
authors.affiliation: Department of Geography, Presidency University, 86/1, College Street, Kolkata, West Bengal 700073 India.
authors.forename: Priyank Pravin
authors.initials: PP
authors.lastname: Patel
authors.affiliation: Department of Geography, Malda Women's College, No. 3, Government Colony, Andigopal, Pirojpur, English Bazar, Malda District, West Bengal 732101 India.
authors.forename: Somasis
authors.initials: S
authors.lastname: Sengupta
keywords: ASTER; Accuracy; Cartosat; DEM; Morphometry; SRTM; Topographical maps