WERA is an Oceanographic HF Radar providing simultaneous measurement of:
- Surface currents maps
- Ocean waves parameters and maps
- Wind direction (wind speed under development)
These measured data are available
- Over long distances (up to 200 km) and large areas
- with good temporal resolution (complete data set within less than 10 minutes)
- with high spatial resolution (down to 250 m)
Feature list (click here)
Principals of Operation
The WERA system (WavE RAdar) is a shore based remote sensing system using the over
the horizon radar technology to monitor ocean surface currents, waves and wind direction (Gurgel, 1999).
This long range, high resolution monitoring system operates with radio frequencies
between 5 and 50 MHz. A vertical polarized
electromagnetic wave is coupled to the conductive
ocean surface and follows the curvature of the earth.
The rough ocean surface interacts with the radio wave
and due to the Bragg effect back-scattered signals can
be detected from ranges of more than 200 km. This
effect was first described in 1955 by Crombie (Crombie,
1955) and the first radar system using that effect
was developed by Barrick et al (Barrick, 1977) at NOAA
in 1977.
The Bragg effect describes the coupling of the electromagnetic
wave with the ocean wave field. To fulfil the Bragg conditions the electromagnetic wave length
needs to have twice the wavelength as the ocean wave, e.g. for a 30 MHz radar signal with Lambda
10 m, the corresponding ocean wave is 5 m. Reflections from waves that fulfil this condition will generate
a dominant signature in the received signal spectrum due to in-phase summation of amplitudes.
Applications
WERA provide a lot of useful data for various applications. Typical users are:
- meteorological institutes
- coastal management (erosion, flooding, pollution, etc.)
- port authorities & harbour management
- environmental monitoring & research
- oil & gas industries
- oceanographic researchers
- vessel traffic services (ship tracking is under development)
- renewable energy providers (wind farm planning and management)
- component for tsunami warning systems
WERA is manufactured by Helzel Messtechnik of Germany. ASL represents Helzel’s WERA systems in Canada and the United States for sales and service. ASL will support already installed and future WERA systems.
Partial list of references
Coastal Radar "WERA", a tool for Harbour Management (pdf 761 KB) Thomas Helzel, Vincent Mariette, Marc Pavec, 2010
HF Radar WERA Application for Ship Detection and Tracking (pdf 1,2 MB)
Anna Dzvonkovskaya, Klaus-Werner Gurgel, Hermann Rohling, Thomas Schlick, 2009
Future Contribution of HF Radar WERA to Tsunami Early Warning Systems (pdf 1,3 MB)
Anna Dzvonkovskaya, Klaus-Werner Gurgel, 2009
WERA Basics - Remote Ocean Sensing for Currents, Waves and Wind (pdf 837 KB)
T. Helzel, M. Kniephoff, L. Petersen, 2006
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