Digital orographic map of peninsular and insular Italy

This paper describes method and contents of the digital orographic map of peninsular and insular Italy, comprising the islands of Elba, Sicily and Sardinia at 1: 1,250,000 scale. The map was obtained using a modification of a previous proposal to define mountain orders, starting from the SRTM-NASA digital elevation model (90 x 90 m cell). The method, comparable to the well known drainage network ordering system, uses the topographic concepts of key contour, key saddle, summit point, prominence, and others. It was implemented in a step-by-step GIS-based procedure in order to automatically identify, delimit and order mountains and hills. The procedure permits the derivation of the parent relationship between orographic entities and organizes the ordered mountains in an orographic hierarchy. The orographic mapping system is able to produce an orographic dataset from DEM's, organize orographic geodatabases and manage mapping tools in many research fields. The map here presented is particularly useful to support interdisciplinary studies in tectonic geomorphology, topo-climatology, regional hydrology and landscape ecology at national scale.