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In this paper we study the retrieval of internal wave (IW) signatures from marine radar data. In a first step, IW packet characteristics are determined, which are used to enhance the IW signal by temporal averaging. The IW-enhanced images are then channeled into our IW signature retrieval algorithm, where we employ localized Radon transform techniques to trace the signatures of each individual soliton. From the resulting IW soliton maps, one can easily extract parameters such as wavelength, velocity, and curvature for each soliton. During the Non-Linear Internal Wave Initiative 2006, R/V Oceanus was tracking IWs as they propagated across New Jersey's continental shelf. Our tool provides a first means of studying the spatio-temporal evolution of IW surface signatures as the underlying wave grows and subsequently decays. [ABSTRACT FROM PUBLISHER]

In this paper we evaluate different methods to retrieve wind information from marine radar data. In contrast to traditional in-situ sensors, marine radar wind data cover a large area and therefore are much less susceptible to air flow distortion by the platform. Unlike previous studies that have been limited to fixed-platform data, this study includes data from a quasi-stationary and moving platform. Images collected with a standard marine HH-polarized X-band radar operating at grazing incidence angle exhibit a single intensity peak in the upwind direction. Marine radar images that are averaged over about 1 min may also show wind streaks, which are usually well-aligned with the mean surface wind direction. Here, we use both phenomena to retrieve wind directional information and compare results to determine the best approach under the given conditions. To retrieve wind speeds, an empirical model function which relates average backscatter intensity to wind speed is developed. [ABSTRACT FROM PUBLISHER]