COMPARATIVE ANALYSIS OF CARTOSAT, ASTER AND SRTM DIGITAL ELEVATION MODELS FOR KANCHEEPURAM WATERSHED

3-D display of topography forms can be collected from Digital Elevation Model (DEMs). Based on the topographical representations watershed margins can be drawn and detail landscape study of the watershed area can be done. For Indian region ASTER, SRTM, CARTOSAT etc., are freely available DEMs acquired by remote sensing technology; utility of such DEMs concerning their accuracy is a topic studied by many remote sensing researchers. The work relay on analyzing the accuracy of DEMs, which are CARTOSAT-DEM (Optical based satellite data),SRTM-DEM (Microwave based satellite data), ASTER-DEM (Thermal based satellite data).The study carried out over Kancheepuram basin of palar river. Shuttle Radar Topographic Mission (SRTM) (30 m), optical stereo pair from ASTER (30 m) and CARTOSAT (10 m) used for the study. The studies shows the parameter values of the stream of CARTOSAT-DEM are higher than SRTM-DEM and ASTER-DEM but the values of elevation of CARTOSAT-DEM are lower as it is geoid based model