The multi-angle view of MISR detects oil slicks under sun glitter conditions

We tested the use of the Multi-angle Imaging SpectroRadiometer (MISR) for detecting oil spills in the Lake Maracaibo, Venezuela, that were caused by a series of accidents between December 2002 and March 2003. The MISR sensor, onboard the Terra satellite, utilises nine cameras pointed at fixed angles, ranging from nadir to +/- 70.5 degrees. Based upon the Bidirectional Reflectance Factor, a contrast function and a classification accuracy assessment, it is shown, for two images examined under sun glint conditions, that the MISR sensor provides a better capability for oil spill discrimination, than the single-view MODIS-250 m data. Analysis of the multi-angle MISR red band indicates that oil spills appear with greater contrast in those view angles affected by sun glitter as a result of local changes in surface roughness caused by the hydrocarbons. Although limited by cloud cover, the capability of the MISR instrument for oil spill discrimination, together with its weekly temporal resolution and open data access, have the potential for improving the operational monitoring of oil releases. (c) 2006 Elsevier Inc. All rights reserved.