A COMPARISON OF ALGORITHMS FOR EXTRACTING SIGNIFICANT WAVE HEIGHT FROM HP RADAR OCEAN BACKSCATTER SPECTRA

A comparison is made between three different but related algorithms fo r the extraction of rms wave heights from high frequency ocean backsca tter radar spectra. All three methods are based on the ratio of second - to first-order energies as developed by Barrick, and each was scaled so that the mean values of the radar analysis results and the corresp onding wave buoy data were zero. The rms difference between the radar wave heights and those from the buoy was taken as a measure of fit, an d the recommended algorithm had an rms difference value of 7 cm. Barri ck's algorithm (after scaling), which uses a weighted second-order ene rgy integral, performed marginally better than the others. The conditi on requiring wind directions other than close to orthogonal to the rad ar beam is retained in the recommended algorithm but is not evaluated because of sparsity of data. The algorithm for extraction of rms wave heights is validated against the buoy data over rms wave height ranges from about 0.2 to 0.7 m.