Influence of the elevation accuracy in the updating of large scale geo-databases in mountain urban areas using IKONOS images

Map production and revision in mountain areas by means of high resolution satellite images showed to be a difficult task. This paper investigates the influence of the elevation accuracy in the updating of large scale geo-databases (geo-DBs) in a mountain urban area of the Italian Western Alps using high resolution panchromatic IKONOS images. A simulation of 1:10,000 scale geo-DB update was performed for the city of Sauze d’Oulx (Susa Valley, Italy) and tested with respect to the Regional technical specifications recently adopted in northern Italy. Finally, results were compared to the official geo-DB available for the test site. Results show that, depending on the digital elevation model’s accuracy used, it is possible to satisfy the requirements for the residual’s tolerance but not those for residual’s mean and standard deviation, thus high resolution DEMs may be needed for updating large scale geo-BDs in mountain areas.