Dynamic Threshold Oil Spill Detection Algorithm for Landsat ETM+

Abstract

Oil spill detection algorithms for the low spectral resolution of high spatial resolution land satellite images are currently limited. Some algorithms are based on the difference of the reflectance between the seawater and the oil spill; however, a proper threshold to detect the oil spill pixel from seawater pixel is much more difficult to define. This paper proposes a new dynamic threshold oil spill detection algorithm for the Landsat ETM+ for demonstration purposes. The new MOD09A1 Version 6 surface reflectance ocean products all year round were selected for constructing the monthly priori surface reflectance database for the dynamic threshold calculations. The 6S model simulates the relationship between the surface reflectance and the apparent reflectance with different geometric parameters, atmospheric models, and aerosol optical depths. The dynamic threshold models are established based on the simulated relationship by the 6S model. The Landsat ETM+ images with oil spill that happened in the Gulf of Mexico were collected and analyzed. The results indicate that the proposed algorithm showed a better result of oil spill detection in high accuracy.