Anonlinearshort-wave-averaged(surfbeat)modelispresented.ThemodelisbasedonthatofRoelvink(1993),butthenumericaltechniquesusedinthesolutionarebasedontheso-calledweighted-averagedflux(WAF)method(egWatsonetal.,1992),withtime-operatorsplittingusedforthetreatmentofsomeofthesourceterms.Thismethodallowsasmallnumberofcomputationalpointstobeused,andisparticularlyefficientinmodellingbreakinglongwaves.Theshort-wave(orprimary-wave)energyequationissolvedusingamoretraditionalLax-Wendrofftechnique.Resultsofvalidationindicatethatthemodelperformssatisfactorilyinmostrespects.
