Investigating the radar scattering response of different land-features in the Greater Cairo area of Egypt, using the full-polarimetric SAR data

Abstract

The full polarimetric Synthetic Aperture Radar (SAR) data offers plentiful information about the geology, geomorphology, hydrology, land cover and soil classification and therefore helps in assessing their potential for development. In this paper, the fullpolarimetric SAR (ALOS/PALSAR L-band sensor) data used for mapping different geological units and land features, which are covering some parts of the Greater Cairo area, Egypt. This paper includes data collection, data interpretation, and a validation tool, as well as methodology and preliminary findings. The ALOS/PALSAR images were extracted, decomposed, filtered and geo-referenced. Unsupervised classification scheme with 5 classes was performed for Radar data using (Wishart H-A-α unsupervised classifier), and it exposed to the supervised classification technique with the assistance of the published geologic and geomorphological maps and the high resolution Landsat images ratio techniques. These five classes are categorized as follows; Urban areas: which covers 22% of the study area, Agriculture: canopy covers 53% of the study area, The Nile: about 73 km of the Nile passing through the study area, and two geological Units, Te (Tertiary, which represents sands and sandstones with clay and marl), and Tp (Tertiary Pliocene, which represents sands, sandstone and gravels). Moreover, the classification accuracy assessment (CAA) was performed for the obtained results using 327 ground control points. The CAA showed classification accuracy around 81.82% with Kappa coefficient of 0.8344. This research shows that using full-polarimetric ALOS/PALSAR data, the land cover and geology of Greater Cairo, Egypt, can be accurately mapped without suffering and wasting time, effort, or facing hazards.