Ocean Applications

M Migliaccio,F Nunziata,A Marino,C Brekke,S Skrunes

doi:10.1007/978-3-030-56504-6_6

Abstract

AbstractIn this chapter, the most promising techniques to observe oil slicks and to detect metallic targets at sea using polarimetric synthetic aperture radar (SAR) data are reviewed and critically analysed. The detection of oil slicks in SAR data is made difficult not only by the presence of speckle but also by the presence of, e.g. biogenic films, low-wind areas, rain cells, currents, etc., which increase the false alarm probability. The use of polarimetric features has been shown to both observe oil slicks and distinguish them from weak-damping look-alikes but also to extract some of their properties. Similarly to oil slicks, the same factors can hamper the detection of metallic targets at sea. The radiometric information provided by traditional single-channel SAR is not generally sufficient to unambiguously detect man-made metallic targets over the sea surface. This shortcoming is overcome by employing polarimetry, which allows to fully characterize the scattering mechanism of such targets.

Highlights

The two main ocean applications analysed are related to oil slicks and metallic target detection.synthetic aperture radar (SAR) oil slick observation is physically possible under low-to-moderate wind conditions (~3–12 m/s), because an oil slick damps the short gravity and capillary waves and reduces the friction velocity generating a region of lowA
The location of the targets was derived by a map, and it is shown as red boxes in the image
6.4.2.3 Analysis of Multi-polarization SAR Data The methodology applied in the analysis of the SAR datasets includes the following steps:

Summary

Introduction

Tailored filtering techniques must be developed in order to minimize the number of false alarms Within such a context, single-polarization SAR oil slick detection procedures can be generally divided into three phases: dark area detection, feature extraction and oil slick/ look-alike classification. Recent advances in the field show a potential in polarimetric SAR measurements with respect to discrimination between different types of oil or surfactants and in deriving valuable information about oil slicks physical properties. In this showcase, we demonstrate that multi-polarization SAR can be used to obtain key information for pollution response authorities about detected slicks at sea (Skrunes et al 2015). This type of information could limit the number of false alarms as well as expensive actions taken by authorities

Objectives

Methods

Results

Conclusion