| Abstract | Digital elevation models (DEM) represent one of the most important data source for investigating the geophysical science of glaciated regions, not only the Earth's Polar Regions but also the inland ice
caps and the high-mountain ice fields. To name a few applications: (1) multi-date multi-source DEMs enable derivation of 3D glaciers parameters, such as elevation and volume changes, surface displacements, surface mass balance (Krabill et al., 1995;
Vachon et al., 1996; Mattar et al., 1998; Joughin et al., 1996a; Schenk et al., 2005 Bamber and Rivera, 2007 and many others); (2) areas of basin can be determined with highly accurate DEM (Hardy et al., 2000); (3) hazards assessments due to rapid
changes of high mountains environment can be performed with continuous monitoring based on both regular remote sensing observations (Kääb et al., 2005). Stereo-photogrammetry applied to air photos acquired at different dates can be used to
simultaneously computed DEM and velocity fields (Kääb and Funk., 1999). Because most of these applications are addressed in this Book, this Chapter gives a deep in-look only for the generation of DEMs using Earth observation (EO) data from
multi-platform and multi-sensor.
Some data and methods for DEM generation could have some limits (orbit inclination, elevation accuracy and grid spacing, strong terrain slopes) in their usefulness for some applications in glaciated regions.
The synergy of terrestrial, airborne, spaceborne data from various sensors in the visible and microwave spectrum using different methods and algorithms (clinometry, stereoscopy, interferometry and altimetry) could thus overwhelm these limitations.
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