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This study focuses on the quality evaluation of two of the best 1 arc-second public global digital elevation models (DEMs), Copernicus GLO-30 DEM and ALOS AW3D30 DSM, from the perspective of their capability to represent the terrain morphology of a complex alpine landscape, located in the alpine Trentino Province, in the Italian Alps. The analysis is performed on an area of 6210 km 2 , considering a reference DEM derived from a high resolution and accurate airborne Lidar DEM. The quality assessment includes, in addition to a conventional analysis of error statistics on a pixels-by-pixel basis, an ad-hoc analysis on the capability to represent the ne-scale morphology and local roughness. The quality analysis is performed considering the in uence of local morphology and of the different land covers. The ndings show that the two global DEMs have comparable overall quality, but the relative performances change according to local landscape characteristics. Copernicus DEM performance is on average better than ALOS in correspondence of urbanized areas as well in areas without vegetation cover, with gentle slopes and relatively low short-range roughness. ALOS DEM performance is slightly better thanCopernicus in rougher terrain and steeper slopes. In general, both DEMs have poor performances in steep slopes, with a limited capability to describe correctly local morphology. The adoption of these global DEMs for terrain analysis and modelling of earth surface processes should be performed carefully, taking into account the impact of different land covers and of local morphology, including surface roughness.

Mud volcanism is observed in many tectonically active regions worldwide. One of the typical areas of mud volcanic activity is the Taman Peninsula, Russia. In this article, we examine the possibilities of multiscale analysis of remote sensing and morphometric data of different origins, years, scales, and resolutions for studying mud volcanic landscapes. The research is exemplified by the central-northern margin of the Taman Peninsula, where mud volcanism has only been little studied. The data set included one arc-second gridded Advanced Land Observing Satellite World three-dimensional (3D) digital surface model (AW3D30 DSM); a Corona historical declassified satellite photography; high-resolution imagery from an unmanned aerial survey (UAS) conducted with a multi-copter drone DJI Phantom 4 Pro, as well as a series of 1-m gridded morphometric models, including 12 curvatures (minimal, maximal, mean, Gaussian, unsphericity, horizontal, vertical, difference, vertical excess, horizontal excess, accumulation, and ring one) derived from UAS-based images. The data analysis allowed us to clarify the conditions of neotectonic development in the central-northern margin of the Taman Peninsula, as well as to specify manifestations of the mud volcanism in this region. In particular, we were able to detect minor and weakly topographically expressed mud volcanic features (probably, inactive gryphons, and salses), which are hidden by long-term farming practice (e.g., ploughed and covered by soil).