Oil spills on ALMAZ-1 and ERS-1 SAR images: Results from the DOSE-91 experiment

Abstract

This paper presents the results of the oil spill observations using Almaz-1 and ERS-1 SAR images collected in the Norwegian Sea during the Dedicated Oil Spill Experiment (DOSE-91) in 1991. Three artificial spills were released from a vessel in August 1991 and data on sea and weather conditions near the test area were determined. The analysis of the acquired SAR images shows that the reduction of the backscatter from oil-covered sea surface attained values of up to 10-15 dB. For the first time an effect of an intensification of wind waves both within the area of the spill and at the windward edge of the oil spill, expressed as a magnification of the SAR image brightness, was detected. The increase in relative backscatter power was up to 2.0 dB. It is concluded that both Almaz-1 and ERS-1 SARs are valuable tools for oil spill detection and localisation, but that the detectability essentially depended on wind speed, sea state and age of spills. © 2006 Springer-Verlag Berlin Heidelberg.