OIL SPILL DETECTION FROM RADARSAT-1 SYNTHETIC APERTURE RADAR IMAGERY AT NORTHERN ENTRY OF BOSPORUS STRAIT, TURKEY


Ozsoy-Cicek B.

FRESENIUS ENVIRONMENTAL BULLETIN, cilt.23, ss.2909-2918, 2014 (SCI İndekslerine Giren Dergi) identifier

  • Cilt numarası: 23
  • Basım Tarihi: 2014
  • Dergi Adı: FRESENIUS ENVIRONMENTAL BULLETIN
  • Sayfa Sayıları: ss.2909-2918

Özet

Shipping and maritime activities may cause a great amount of oil pollution on the sea surface; such as ship transportation, oil platforms and ports. There are some deterrent applications to provide cleaner and safer seas. Timely identification of extent and source of oil pollution is mandatory for mitigation of its impact and prosecution of the originator. One of the preferred instruments to detect and monitor oil pollution by maritime activities is space-borne active microwave remote sensing at a few 10 m spatial resolution as enabled independent of cloud cover and daylight conditions by Synthetic Aperture Radar (SAR). It allows us to detect oil pollution at the sea surface over a region of a few 100 kilometers at a glance. It is possible to monitor near-real time, continuously or periodically for the region of interest. This and its cost effectiveness is a great advantage over air-borne surveillance activities. Prerequisites for successful oil-spill identification by SAR imagery is a sufficiently high wind speed (above 2 m/s), proper application of SAR image processing techniques, and a careful consideration of SAR imaging geometry and hydrodynamic modulation of the sea surface by oceanic phenomena. This study provides evidence about the widespread occurrence of oil spills in the Black Sea north of Bosporus Strait, Turkey. The preliminary results of an analysis of 12 RADARSAT-1 SAR ScanSAR Narrow images acquired during late summer and fall 2010 and 2012 underline the usefulness of SAR imagery for oil spill detection. Simple image enhancement techniques can permit to obtain information about the character of the oil spill. Application of such techniques is however limited by the environmental conditions and in particular the discrimination of oil spills from natural surface slicks requires additional data and/or more advanced techniques in accordance with published knowledge.