Comparative study of wave parameters derived from spectral and zero-crossing methods

Abstract

Along wave records, collected in deep and shallow waters off Goa, West Coast of India, using ship-borne wave recorder, have been analysed following wave spectrum approach and zero-crossing method (Tucker/Draper method). Comparison of wave parameters obtained from both methods reveals that the significant wave heights (<i>H</i>_s) and zero-crossing periods (<i>T_z</i>) agree resonably well whereas the spectral width parameter (<i>ϵ</i>) and mean crest period (<i>T</i>_c) show some anomalies. Values of <i>ϵ</i> are higher and <i>T</i>_c lower for spectral approach compared to the zero-crossing method. It is envisaged that the use of spectral peak periods in place of <i>T_z</i> or <i>T</i>_c would be more appropriate for wave data sets containing predominant 'sea' and 'swell' components together.