High Frequency (HF) Radar
Principal Investigator: James S. Bonner, Ph.D., P.E.
SERF Contact: John Perez
Sponsors/Support: Texas General Land Office, Texas Higher Education Coordinating Board, National Science Foundation
HF Radar Links
USF West Florida Coastal Ocean Monitoring and Prediction System (COMPS)
Alliance for Coastal Technologies
The University of Alaska SALMON Project Sea-Air-Land Modeling and Observing Network (SALMON)
Mapping Oregon Coastal Ocean Currents
The Southern Central California CODAR Homepage
Coastal Ocean Dynamics Applications Radar (CODAR) C.O.O.L. Homepage
Animations from short mobile deployments of the pair of 25-MHz Radars (Animation will open in a new window)
Corpus Christi Bay (12 KB)
Matagorda Bay (10 KB)
Galveston Beach (10 KB)
Introduction
In an effort to seek and pioneer the use of compelling new technologies for the benefit of coastal communities, the Shoreline Environmental Research Facility has developed two mobile high frequency (HF) radar units. The two mobile radar stations operate on Corpus Christi Bay. SERF is also developing a radar network to monitor surface currents for much of the Texas Gulf Coast. Currently, there four newer radar sites in addition to those operating on Corpus Christi Bay, which are located in Galveston, North Padre Island and Matagorda Island. See the Remote Site listing and the map below for descriptions and locations of sites.
This radar system provides an invaluable
means for collecting real-time measurements of surface circulation
patterns, wave height/direction/period, and wind direction within the
targeted water bodies. A unique feature of an HF Radar system is its
ability to provide real-time measurements over a large area. For example,
surface currents covering most of Corpus Christi Bay can be measured at
nearly 280 locations and on a hourly basis.
HF radar utilizes sophisticated signal processing and specialized hardware to extract the surface conditions from the Doppler shift of the sea echo generated by Bragg scattering of electromagnetic waves from surface water. Bragg scattering is a coherent reflection of transmitted energy by ocean surface waves with wavelengths one-half as long as the transmitted radar waves.
This HF radar will provide the Texas coastal communities key information for use as a navigation aid for ship traffic, scientific studies of the bays, oil-spill control, and recreational uses. The radar system will be able to report the water currents within ship channels, thereby increasing the available information for marine safety. Data from the radar system will also be used to develop and drive bay circulation models. These models will greatly increase understanding of the bay ecosystem. The real-time nature of the system will also be a major asset in the tracking of oil spills and the determination of the best oil spill countermeasure strategy, such as the location of boom and skimmer deployment. The measurements can also be made available to the public for recreational uses such as windsurfing, boating, and fishing.
Key facts about an HF radar system
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Since a single radar site is capable of detecting only the component flow traveling toward or away from the site, two or more sites are needed to resolve a current vector.
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The effective depth of the measurement is quite shallow. (<1m)
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Measurements are determined by averaging information from hundreds of wave crests over a defined area.
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The precision is limited by the frequency resolution of the Doppler spectrum and is typically 2-5 cm/s.
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The accuracy is controlled by numerous factors, such as signal-to-noise ratios, pointing errors, and the geometry of the body of water.
SERF Publications/Manuscripts Relating to HF Radar
A Comparison of Near-surface Current Measurements by ADCP and HF Radar on the West Florida Shelf
Geometric Dilution of Precision of HF Radar Data in 2+ Station Networks
An HF Radar Test Deployment Amidst an ADCP Array on the West Florida Shelf
Development of a Cheap, GPS-based, Radio-tracked, Surface drifter for closed Shallow-water Bays