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Short-Time Ice Drift and Deformation Measurements Using Multi-Mission Synethetic Aperture Radar
(Journal article; Tidsskriftartikkel, 2015-06)
Norway is in a good position regarding frequent access to synthetic aperture radar data. A Norwegian–
Canadian agreement provides large quotas of RADARSAT-2 images used operationally by e.g. the Norwegian
Ice Service. More recently, Norway’s participation in the Copernicus program also allows rapid
access to SENTINEL-1A data. By combining these data sources we can get satellite time series ...
Synthetic Aperture Radar Remote Sensing of Operational Platform Produced Water Releases
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-03)
Oil spill detection services based on satellite synthetic aperture radar (SAR) frequently detect oil slicks close to platforms due to legal releases of produced water. Separating these slicks from larger releases, e.g., due to accidental leakage is challenging. The aim of this work is to investigate the SAR characteristics of produced water, including the typical appearance in HH/VV data, possible ...
Can Mineral Oil Slicks Be Distinguished From Newly Formed Sea Ice Using Synthetic Aperture Radar?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-18)
In this feasibility study discriminating oil slicks and newly formed sea ice using SAR imagery is investigated, using imagery from the L-band high-resolution Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) airborne and the satellite C-band RADARSAT-2 (RS-2) systems. To determine the separability of these two varying but similar appearing low backscatter ocean surfaces, multi-polarization ...
Towards automatic detection of dark features in the Barents Sea using synthetic aperture radar
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-17)
Increased human presence and commercial activities in the Barents Sea (fishing, offshore oil and gas exploration) are amplifying the need for large-scale operational ocean monitoring of the eventual oil spills in the region. The geographical location and climate impose additional constraints on satellite-based monitoring, making it necessary to use Synthetic Aperture Radar (SAR). Dark features or ...
Measurement of Oil Slick Transport and Evolution in the Gulf of Mexico using L-band Synthetic Aperture Radar
(Journal article; Tidsskriftartikkel, 2018-06)
The transport and evolution of a mineral oil slick originating at a seep in the Gulf of Mexico approximately 16 km offshore of the mouth of the Mississippi River is measured using a series of images acquired at 40 minute intervals with the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), an L-band, high resolution, high signal-to-noise instrument operated by the U.S. National Aeronautics ...
Numerical Analysis of Microwave Scattering from Layered Sea Ice Based on the Finite Element Method
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-08-21)
A two-dimensional scattering model based on the Finite Element Method (FEM) is built for simulating the microwave scattering of sea ice, which is a layered medium. The scattering problem solved by the FEM is formulated following a total- and scattered-field decomposition strategy. The model set-up is first validated with good agreements by comparing the results of the FEM with those of the small ...
Effect of Wind Direction and Incidence Angle on Polarimetric SAR Observations of Slicked and Unslicked Sea Surfaces
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-05-12)
The objective of this paper is to investigate the dependency of oil spill observations in polarimetric SAR data on imaging geometry, i.e., on incidence angle and look direction relative to the wind. The study is based on quad-polarization data acquired by the Uninhabited Aerial Vehicle Synthetic Aperture Radar over experimental oil slicks under relatively high winds of 10–12 m/s over an 8-hour period. ...
Quad-Polarimetric SAR for Detection and Characterization of Icebergs
(Conference object; Konferansebidrag, 2016)
This paper evaluates the performance of fully polarimetric SAR data in iceberg detection and characterization. The study aims to explore the potential of RADARSAT-2 SAR data to detect icebergs and growlers in Svalbard that have broken off from the glaciers nearby. To be able to detect iceberg/growlers in a SAR image, a significant contrast between iceberg and background clutter is required. The ...
Analysis of evolving oil spills in full-polarimetric and hybrid-polarity SAR
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-25)
Oil spill detection using a time series of images acquired off Norway in June 2015 with the uninhabited aerial vehicle synthetic aperture radar is examined. The relative performance of a set of features derived from quad-polarization versus hybrid-polarity (HP) modes in detection of various types of slicks as they evolve on a high wind driven sea surface is evaluated. It is shown that the HP mode ...
Comparison Between Dielectric Inversion Results From Synthetic Aperture Radar Co- and Quad-Polarimetric Data via a Polarimetric Two-Scale Model
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-03)
In this study, we compare the retrieval results for the dielectric properties of verified oil slick, acquired using airborne multifrequency synthetic aperture radar. A polarimetric two-scale model was used to invert the radar imagery by first employing solely the co-polarization channels, and then by employing the co-polarization channels in conjunction with the cross-polarization channels, and ...