Strategies for the Automatic Extraction of Water Bodies from TerraSAR-X/TanDEM-X data

Abstract

Medium-resolution SAR satellite data have been widely used for water and flood mapping in recent years. Since the beginning of 2008 high-resolution radar data with up to 1 m pixel spacing of the TerraSAR-X satellite are operationally available. Due to the improved resolution of the sensor more details of the Earth’s surface become visible. A number of different appearances of water bodies in TerraSAR-X data are shown that are relevant for a general water mapping concept. Existing water body detection approaches that have been applied to medium-resolution SAR data are reviewed with regard to their applicability for TerraSAR-X data. As a complementary mission to TerraSAR-X the launch of TanDEM-X is planned for October 2009. The data of both satellites will be used to generate a global DEM (Digital Elevation Model) with an interferometric data acquisition concept. As a byproduct to the DEM dataset a global water mask will be derived from the SAR data. The concept for this water detection process within the TanDEM-X project is introduced in this paper.