Validation of the DLR Global Urban Footprint in rural areas: A case study for Burkina Faso

Earth observation from space has often been used for the mapping of settlements on a global scale. The recently developed Global Urban Footprint (GUF - 2011/2013) aims at a global settlement classification with an improved geometric resolution based on data from the TerraSAR-X/TanDEM-X missions. Due to manifold challenges the settlement classifications are subject to distinct accuracy variations across global landscapes. This study presents a systematic accuracy assessment of the GUF product for the case study of Burkina Faso, an African country characterized by mainly rural, small-scale and fragmented settlement structures. As a first step, we conduct a relative, non site-specific comparison of available national and global human settlement layers (HSL) on national scale by the quantification of total settlement areas and derived density measures. In a second step, we aim at an absolute accuracy assessment on local scale using appropriate reference data. Therefore we use absolute accuracy measures based on the error matrix as well as pattern-based evaluation techniques with regard to physical settlement variations such as settlement size. Results clearly show the enhanced mapping capabilities of new high resolution global settlement products such as the GUF, especially for rural areas.