Theoretical investigation of microwave scattering characteristics of ocean surface with oil spills

2005 ◽  
Author(s):  
J. Wu ◽  
Y. Zhang ◽  
H. Wang
Keyword(s):  
Theoretical Investigation ◽  
Oil Spills ◽  
Ocean Surface ◽  
Microwave Scattering

scholarly journals Application of multifractal analysis to the study of SAR features and oil spills on the ocean surface

2014 ◽  
Vol 21 (2) ◽  
pp. 439-450 ◽  
Author(s):  
A. M. Tarquis ◽  
A. Platonov ◽  
A. Matulka ◽  
J. Grau ◽  
E. Sekula ◽  
...  
Keyword(s):  
Oil Spills ◽  
Multifractal Spectrum ◽  
Speckle Noise ◽  
Ocean Surface ◽  
Eddy Diffusivity ◽  
Dynamic State ◽  
Full Potential ◽  
Sar Images ◽  
Surface Diffusivity ◽  
Observation Methods

Abstract. The use of synthetic aperture radar (SAR) to investigate the ocean surface provides a wealth of useful information that is very seldom used to its full potential. Here we will discuss the application of multifractal techniques to detect oil spills and the dynamic state of the sea regarding turbulent diffusion. We present different techniques in order to relate the shape of the multifractal spectral functions and the maximum fractal dimension to the behaviour of the ocean surface. We compare eddy and sheared dominated flows with convective driven flows and discuss the different features and observation methods. We also compare the scaling of different oil spills detected by means of SAR images. Recent spills and weathered ones are selected and compared to investigate their behaviour in different spatial and temporal ranges. We calculate the partition function based on the grey intensity value of each SAR pixel deriving several types of multifractal spectra as a function of spill residence time estimated for each image. Image manipulations are seen to reduce the speckle noise and thus distinguish much better the texture of the oil spill images. The results are used to discuss how eddy diffusivity may be estimated and used in a description of the ocean surface using a simple turbulence kinematic simulation model to predict the shape of oil spills. Differences in the multifractal spectrum among SAR images may detect the slicks due to plankton and also provide information on the age of the oil spills, on the Lagrangian turbulent structure and on ocean surface diffusivity.

scholarly journals Bayesian Statistics of Wide-Band Radar Reflections for Oil Spill Detection on Rough Ocean Surface

2019 ◽  
Vol 7 (1) ◽  
pp. 12 ◽  
Author(s):  
Bilal Hammoud ◽  
Fabien Ndagijimana ◽  
Ghaleb Faour ◽  
Hussam Ayad ◽  
Jalal Jomaah
Keyword(s):  
Bayesian Statistics ◽  
Oil Spills ◽  
Probabilistic Approach ◽  
Single Layer ◽  
Wide Band ◽  
Ocean Surface ◽  
Probability Of Detection ◽  
Dual Frequency ◽  
Multiple Observations ◽  
The Difference

In this paper, we present a probabilistic approach which uses nadir-looking wide-band radar to detect oil spills on rough ocean surface. The proposed approach combines a single-layer scattering model with Bayesian statistics to evaluate the probability of detection of oil slicks, within a plausible range of thicknesses, on seawater. The difference between several derived detection algorithms is defined in terms of the number of frequencies used (within C-to-X-band ranges), as well as of the number of radar observations. Performance analysis of all three types of detectors (single-, dual- and tri-frequency) is done under different surface-roughness scenarios. Results show that the probability of detecting an oil slick with a given thickness is sensitive to the radar frequency. Multi-frequency detectors prove their ability to overcome the performance of the single- and dual-frequency detectors. Higher probability of detection is obtained when using multiple observations. The roughness of the ocean surface leads to a loss in the reflectivity values, and therefore decreases the performance of the detectors. A possible way to make use of the drone systems in the contingency planning is also presented.

scholarly journals Experimental study of C-band microwave scattering characteristics during the emulsification process of oil spills

2020 ◽  
Vol 39 (7) ◽  
pp. 135-145
Author(s):  
Sijing Shu ◽  
Junmin Meng ◽  
Xi Zhang ◽  
Jie Guo ◽  
Genwang Liu
Keyword(s):  
Experimental Study ◽  
Oil Spills ◽  
Microwave Scattering ◽  
Emulsification Process

Microwave Scattering from the Ocean Surface (Short Papers)

1975 ◽  
Vol 23 (12) ◽  
pp. 1053-1058 ◽  
Author(s):  
W.L. Jones ◽  
W.L. Grantham ◽  
L.C. Schroeder ◽  
J.W. Johnson ◽  
C.T. Swift ◽  
...  
Keyword(s):  
Ocean Surface ◽  
Microwave Scattering

Microwave Scattering from the Ocean Surface

2005 ◽  
Author(s):  
W.L. Jones ◽  
W.L. Grantham ◽  
L.C. Schroeder ◽  
J.W. Johnson ◽  
C.T. Swift
Keyword(s):  
Ocean Surface ◽  
Microwave Scattering

scholarly journals Persistent Lagrangian Transport Patterns in the Northwestern Gulf of Mexico

2019 ◽  
Vol 49 (2) ◽  
pp. 353-367 ◽  
Author(s):  
Matt K. Gough ◽  
Francisco J. Beron-Vera ◽  
María J. Olascoaga ◽  
Julio Sheinbaum ◽  
Julien Jouanno ◽  
...  
Keyword(s):  
Gulf Of Mexico ◽  
Coherent Structures ◽  
Oil Spills ◽  
Deep Ocean ◽  
Surface Current ◽  
Ocean Surface ◽  
Shelf Break ◽  
Lagrangian Transport ◽  
Free Running ◽  
Transport Patterns

AbstractPersistent Lagrangian transport patterns at the ocean surface are revealed from climatological Lagrangian coherent structures (cLCSs) computed from daily climatological surface current velocities in the northwestern Gulf of Mexico (NWGoM). The climatological currents are computed from daily velocities produced by an 18-yr-long free-running submesoscale-permitting Nucleus for European Modelling of the Ocean (NEMO) simulation of the Gulf of Mexico. Despite the intense submesoscale variability produced by the model along the shelf break, which is found to be consistent with observations and previous studies, a persistent mesoscale attracting barrier between the NWGoM shelf and the deep ocean is effectively identified by a hook-like pattern associated with persistent strongly attracting cLCSs. Simulated tracer and satellite-tracked drifters originating over the shelf tend to be trapped there by the hook-like pattern as they spread cyclonically. Tracers and drifters originating beyond the shelf tend to be initially attracted to the hook-like pattern as they spread anticyclonically and eventually over the deep ocean. The findings have important implications for the mitigation of contaminant accidents such as oil spills.

scholarly journals Retrieval of Oil–Water Mixture Ratio at Ocean Surface Using Compact Polarimetry Synthetic Aperture Radar

2019 ◽  
Vol 11 (7) ◽  
pp. 816 ◽  
Author(s):  
Haiyan Li ◽  
William Perrie ◽  
Jin Wu
Keyword(s):  
Synthetic Aperture Radar ◽  
Covariance Matrix ◽  
Oil Spills ◽  
Ocean Surface ◽  
Synthetic Aperture ◽  
Water Mixture ◽  
Mixture Ratio ◽  
Oil Water ◽  
Sar Imagery ◽  
Aperture Radar

The oil–water mixture ratio for oil spills on the ocean surface is an important parameter for volume estimation of oil spills, response strategy for the oil spills, cleanup operations, and remediation planning for the impacts on wildlife. Hybrid-polarized (HP) mode compact polarization (CP) synthetic aperture radar (SAR) imagery will soon be available with the launch of the RADARSAT Constellation Mission. The advantage of the proposed new SAR system is that CP images will have wider swath and shorter revisit time compared to quad-polarization (QP) images, which are presently available from space-borne and air-borne SAR. We present a methodology to retrieve the oil–water mixture ratio at the ocean surface using CP SAR imagery. We emulated the HP mode of CP SAR image using Uninhabited Aerial Vehicle SAR (UAVSAR) L band observations collected on June 23rd 2010 over the site of the Deep Water Horizon drilling rig. The gap between elements ratio of CP SAR covariance matrix and that of QP SAR Sinclair matrix is bridged. Numerical optimization and look up table methods are used to relate the oil–water mixture ratio to elements of the covariance matrix for the HP data backscatter. The mixture ratio estimates determined from the ratio of diagonal elements of the covariance matrix for HP mode CP data are compared with results retrieved from the co-polarization ratio from the original QP SAR observations. Results from the proposed methodology for SAR images captured in the HP mode of CP data are shown to compare favourably to observed in situ data of the mixture ratios.

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