Katrin Hessner

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A method to estimate sea surface elevation maps from marine radar image sequences is presented. This method is the extension of an existing inverse modeling technique to derive wave spectra from marine radar images, which assumes linear wave theory with temporal stationarity and spatial homogeneity of the observed sea surface elevation. The proposed(More)
The measurement of ocean waves and surface currents with a nautical radar is based on the spatial and temporal structure analysis of radar images of the sea surface. These radar images are generated by the interaction of HHpolarized electromagnetic waves with the sea surface ripples at grazing incidence. In these radar images the sea surface is visible as(More)
New analytical, circular eddy solutions of the nonlinear, reduced-gravity, shallow-water equations in a rotating system are presented. While previous analytical solutions were limited to the description of pulsons, which are oscillating, frontal, warm-core eddies with paraboloidic shape and linear velocity components, the new solutions describe more general(More)
Images generated by a common ship’s navigation radar contain wave information. Digital techniques allow rapid acquisition and processing of such data. Since the radar is looking at extreme grazing angles, effects like diffraction and shadowing dominate the backscatter mechanism. As a consequence, no reliable backscatter model is available that allows(More)
The ocean wave signatures within conventional noncoherent marine X-band radar (MR) image sequences can be used to derive near-surface current information. On ships, an accurate near-real-time record of the near-surface current could improve navigational safety. It could also advance understanding of air–sea interaction processes. The standard shipboard MR(More)
The wave and current monitoring system WaMoS II is a remote sensing system based on a nautical X-Band radar generally used for navigation and ship traffic control. It has been used in recent years to monitor sea state information from moored platforms, coastal sites and moving vessels. A nautical radar can scan the sea surface over a large area (~ 10km )(More)
This work presents the estimation of wave field properties derived from X-band marine radar measurements taken close to coastal locations, where the wave fields are affected by the finite water depth conditions. The work is focused on the detection of individual waves and their related characteristics, such as the estimation of the local and instantaneous(More)
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