Quantcast
Last updated on April 19, 2014 at 21:20 EDT
Elbe River Germany
663 of 1101

Elbe River, Germany

January 19, 2006
This Envisat radar image of the Elbe valley in Sachsen (Germany) was taken on 19 August 2002, around 11:30 (local time). It shows the flooded areas in black or blue. These areas are particularly evident around the city of Riesa. This image demonstrates the increased capabilities of the Advanced Synthetic Aperture Radar (ASAR) onboard the Envisat spacecraft compared with the SAR sensors on the earlier ERS generation of satellites. While offering a continuity of service to users, Envisat's ASAR instrument is the first permanent spaceborne radar to incorporate dual-polarization capabilities - the instrument can transmit and receive signals in either horizontal or vertical polarization. This Alternating Polarization (AP) mode can improve the capability of a SAR instrument to classify different types of terrain, because the reflective properties of a surface are dependant on the polarization of the incoming radar signal. The use of more than one type of polarization provides valuable extra information.

Technical Information:
  • Satellite: Envisat
  • Instrument: ASAR
  • Acquisition: 19-Aug-2002
  • Orbit nr: 02452
  • Center coordinates: lat. 51.37, lon. 14.00