DISTRIBUTIONS OF BREAKING DETECTION INDEXES ON BREAKING WAVE AND NON-BREAKING WAVE

Based on the synchronous in situ trigger signal for breaking events,using multi-breaking criterion to classify the breaking and non-breaking waves,the distribution differences of some breaking criterion indexes on breaking and non-breaking waves were examined.The results indicate that for the detection indexes in dynamic criterion and kinematic criterion were calculated via Hilbert transformation,their distributions on breakers and non-breakers were well separated,and there are stable threshold values for breaking criteria;the detection index of dynamic criterion calculated via wavelet transformation is not so good,there is no stable threshold value to distinguish breaking waves from non-breaking waves;and for geometric indexes,such as wave steepness,forward and backward steepness,horizontal and vertical crest asymmetry,and for wave height,maximum wave elevation,wave length,wave period,and even for instantaneous wave slope,there is no enough difference between their values on breaking and non-breaking waves,the breaking criteria based on such indexes are not effective.