Evaluation of high resolution MODIS-Aqua data for oil spill monitoring

Abstract

The MODIS - Aqua high-resolution imagery were exploited to detect and monitor oil spills. An evaluation criterion has been established to study its potential. The study focused on two oil spill events: Lake Maracaibo, Venezuela (January 18-20, 2003) and Jiyeh power station oil spill, Lebanon (July 15-31, 2006). The images were examined at level-1B (only geometrically corrected) and level-2 (geometrically and atmospherically corrected) data processing levels. The level-2 data lacked the sufficient contrast range, because of the rigorous atmospheric correction, while the level-1B data were found to be suitable. The 250-m data at 645 and 859 nm and 500-m, interpolated to 250-m, at 469, 555, 1240, and 2130 nm were analyzed. The methodology included examination of individual bands and evaluation of 30 band ratioing combinations to improve the contrast of oil spills in the images. The evaluation criteria were based on both visual and parametric. The metrics involved are: mean contrast function and feature matching. In addition, bi-directional reflectance distribution function (BRDF) at 469, 555, and 645 nm wavelengths, were also evaluated using the same criteria. The study found that at appropriate view-angle, MODIS-Aqua high-resolution is suitable for oil spill detection at 250-m band. When the view-angle is not appropriate, the combination of mid-IR bands with shorter wavelengths improved the feature matching.