Representing spectral changes in seasonal ocean wave patterns using interquartile ranges

Abstract

This article presents the changes observed in the structure of wind-wave spectra due to wave period variability. A large set of wave data is analysed as well as a robust spectral representation of the sea states is applied for this purpose. After estimating and verifying the joint distribution of the sea states, a significant wave height interval is selected to then observe the climatic changes as the wave periods vary. For this fixed limit of wave height, three wave periods intervals that contain the maximum values of sea states occurrence are then selected. These different groups of data are also evaluated separately considering its seasonality by a robust statistical metrics. Furthermore, for each dataset these changes in seasonal patterns recorded by the spectra are presented using the inter quantiles ranges metrics. The resulting data from different ensemble of spectra are compared with the conventional approach that consider the maximum and minimum envelopes to represent the climatic spectrum with the robust representation (using inter quantile ranges) followed in the present work.