Einzelbeispiel satellitengestützter Erderkundung
The ERS-1 SAR scene represents about 100 by 100 km and is composed of:
Red: 7 Dec 1992
The multitemporal ERS-1 SAR scene is composed of one summer (13 Sept.) and two winter (7 Dec. and 15 Feb.) data acquisitions and reveals unexpected seasonal changes in this fully desertic area, which is indicated by the colours. In contrast to this the plateau is presented in white and grey, i.e. without any change. This old sedimentary rock, some 200m above the sandy desert includes the Richat ring structure made of a series of concentric quartzite ridges which is assumed to be the remains of an eroded magmatic intrusion.
The yellowish sand desert consists of large longitudinal dunes of some 300m, measured from crest to crest, but also of active (much smaller but well developed) dunes generated by winds rotated slightly towards north with respect to the large ones.
(ERS Data Ulilization Section ESA/ESRIN)
Quelle: ERS Spaceborne Radar Imagery, Copyright ESA 1996