Mr. Robert Forney Dr. Hugh Roarty Dr. Scott Glenn Measuring Waves with a Compact HF Radar MTS/IEEE OCEANS15 October 2015 Washington DC

MARACOOS HF RADAR NETWORK 5 MHz13 MHz25 MHz U Mass WHOI U Conn URI Stevens Rutgers Delaware ODU/CIT UNC Stations in Total

Radial Velocity Measurement

Combine Radial Velocity Measurements

Total Vector Surface Current Measurements

Spectra From the Radar

National Waves Plan LocationNew Sensors Total Acquisition Cost Unit Acquisition Cost Offshore13$3.9M$300,000 Outer Shelf17$3.9M$229,000 Inner Shelf19$2.3M$120,000 Coastal66$7.9M$120,000

West Coast HF Radar Measurements Average correlation with wave buoys: 0.88 Root mean square difference: 0.53 m Standard Deviation of difference:0.48 m 2011 Journal of Sensors

West Coast Bathymetry 30 meter isobath Long (2011) used five 13 MHz HF Radars along California coast

Second Order - Waves First Order - Currents

New Jersey Study Area 13 MHz 30 meter isobath BRAD

Range Cell 2 for all HF radar measurements

Bragg Period at 13.5 MHz is XX

Temporal Coverage Feb-Jun 2015 Averaging Time (minutes) Temporal Coverage 3032% 6040% 10043% 12045% 18049%

Frequency (MHz) Sweep Rate (Hz) Doppler Bins Time FFTCSS Avg/Out Radial Avg/Out CSS per Radial File m 04s60/30180/ m 16s15/1075/ m 16s15/1075/307 SeaSonde AcquisitionCSProAnalyze Spectra Existing SeaSonde Settings 15

Radio Frequency (MHz) Radio Wavelength (m) Bragg Wavelength (m) Ocean Wave Period (s) Deep Water Depth (m) Wave Height Saturation (m) Radio Frequency (MHz) Radio Wavelength (ft) Bragg Wavelength (ft) Ocean Wave Period (s) Deep Water Depth (ft) Wave Height Saturation (ft)

October 4, 2015 Nor’easter Hurricane Joaquin

SILD 25 MHz

Wave Height Wave Period

Wave Height Wave Period

SILD 25 MHz Current Wind

RESULTS HF Radars are operating throughout Mid Atlantic and other regions of the US Main focus is for measuring surface currents Secondary application can be for measuring near shore waves