Analysis of the measured directional spectra
Developing efficient and useful algorithms for the interpretation of the inverted data is also a subject of research that has been funded by EPSRC/MTD. Methods from computational geometry have been developed to enable the automatic identification of wave modes of different origin eg locally wind-driven waves, swell. That method was required because at the time it was developed we were obtaining the directional spectrum on a non-uniform wavenumber grid.
Our newer numerical methods provide the data on a uniform grid and so a different technique has now been implemented and we partition our derived directional spectra during the real-time processing.
We participated in the COST Action 714 on directional wave spectra. This was seeking ways to promote the use of directional wave spectral information and to further develop measurement techniques particularly using remote sensing. A book, Measuring and analysing the directional spectra of ocean waves, has been edited by members of the COST Action: D. Hauser, K. Kahma, H. E. Krogstad, S. Lehner, J. Monbaliu and L. R. Wyatt. The book was published by the COST office, Luxembourg.
Maps showing wind sea (a) and swell (b) off the Holderness coast obtained by partitioning the directional spectra at each location.