Wave climate

Wave climate is the statistical description of the wave conditions at a site over years: the joint distribution of significant wave height, peak period, and direction, with the extreme values for design. It is built from measured buoy or satellite data and hindcast spectra, then fitted to an extreme-value distribution to give the design wave at a chosen return period, often 1 in 100 years for a breakwater. The climate drives armour size through the Hudson or Van der Meer formula, the longshore transport rate, and the overtopping discharge. The directional spread sets which structures and which beach respond to which storms.