Dynamic Integrated GIS Enhancement and Support Tools. First step: Analysis of Available Data

Already existing Digital Elevation Models (DEMs) contain inaccuracies that prevent them for being reliably used to support decision-making in emergencies. The objective of this paper is to present the framework for a set of Dynamic Integrated GIS Enhancement and Support Tools (DIGEST) that aims to reduce inaccuracies of existing DEMs for “on-the-fly” applications. DIGEST allows a more effective use of DEMs, particularly for management during a natural or manmade disaster. The DIGEST system will be integrated in an existing geographic database, with tools targeted to create quality information for the available data, and to define appropriate scale required for an event simulation based on the limitations of existing topographic data. The new system tools will also dynamically extract features of topographic relevance from the most recent non-photogrammetric visible, infrared and thermal imagery. The extracted features will be employed to detect changes to topographic features in the already available DEMs. Quality enhancement of the DEM will be achieved through the integration of the extracted topographic features using data conflation algorithms. In the current paper, an analysis of widely available DEMs is present demonstrating the potential of DIGEST by focusing on the potential impact on decision-making by using freely available data from the Shuttle Radar Topography Mission and other DEMs available from Geospatial Data Clearinghouse servers established by the Federal Geographic Data Committee (FGDC).