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This paper explores the possibility of using real-time measurements of surface current vectors and U10 wind vectors to estimate the 3D current field. Calibration is required by using an ADCP over a one-month period to find the roughness parameter, z0, for the logarithmic boundary layer. Ekman and Stokes current profiles are derived from the U10 wind vector. This methodology uses some of the assumptions...
The phased array HF ocean radar installed at the Port of Rotterdam gives good quality near real-time information on surface currents for port management. This paper examines the potential to infer current profiles from HF radar and wind station data using prior knowledge of the site. It is shown that tidal currents follow a logarithmic boundary layer profile, and the wind-driven currents have an approximately...
A VHF ocean radar system was deployed for one month in a salt marsh in coastal Georgia, USA. In this environment, radar backscatter from the marsh grass is highly attenuated and scatter from water in the narrow creeks has a broad band of Doppler shift due to the horizontal variation in water speed across the channel. By assuming a monotonic velocity profile from the edge to the middle of the channel,...
Surface current velocity fields measured every 10 min by a high-frequency ocean radar system (HF radar) located at the southern Great Barrier Reef (GBR), Australia, were used to compute Lagrangian trajectories (radar-based trajectories). The radar-based trajectories were validated against surface-drogued satellite tracked drifting buoys released on the shelf inside the reef lagoon and on the continental...
The area around the grounding site of the Shen Neng 1 in Great Barrier Reef waters 0n 3 April 2010 was monitored by an HF radar and several Acoustic Doppler Profilers. The HF radar is shown to compare well with the Profilers at the mooring sites. The radar data was used to produce a time series of surface currents at the site during the grounding and throughout the subsequent salvage and clean-up...
Surface currents and ocean swell are measured using an HF radar with a compact cross-loop antenna design. This unique direction-finding radar has been widely used for long-term monitoring and for coastal oceanography applications over the last ten years. Numerous studies have evaluated errors associated with these devices under a host of environmental and seasonal conditions, and reliable comparisons...
Surface coastal currents mapped by a pair of high frequency ground-wave radars (HFR) have been used to predict Lagrangian trajectories in the proximity of Heron Island (Capricorn Bunker Group, Great Barrier Reef, Australia), and to compare with the current data measured by an Acoustic Doppler Current Profiler (ADCP) at three mooring stations. Overall the HRF and ADCP absolute current speeds showed...
One simple way to evaluate errors in the radial components of surface currents is to compare the values measured from two separate radars along the baseline joining them. This is best done at the midpoint of the baseline where the areas sampled by the radars are equal. This cannot be done if the baseline is close to the coast or over land. Here we compare radial components along the perpendicular...
A direct measure from the spectra of HF radar sea echoes is the ratio of energy in the dominant Bragg peaks. If a single lobe is assumed for the directionality then two radar stations can be used to provide a closed solution for the direction of the lobe. In this work we examine the potential of using just one radar station to derive directional information about wind fields. It is shown that HF radar...
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