568 



lands) . This is gratefully acknowledged. Consider- 

 able support in terms of logistics, groundtruth 

 data, meteorological observations, etc. was received 

 from colleagues in the framework of JONSWAP and this 

 is greatly appreciated. 



NOTATION 



A area of spatial integration 



Cm phase speed of component fm 



Cg group velocity 



D(9) standard directional distribution function 



E(k) spectral density in k-space 



E(k,e) spectral density in k,9-space 



E(f,e) spectral density in f,9-space 



E(f) spectral density in f-space 



f frequency 



g acceleration due to gravity 



h instantaneous surface elevation 



H(k) Fourier transform of surface elevation 



J Jacob ian 



k wavenumber vector k = (kx,ky) 



k wavenumber, modulus of wavenumber vector 



kjn waveniimber at peak of wavenumber vector 



spectrum of locally generated wind sea 



L„ dimension of area of analysis in x-direction 



Ly dimension of area of analysis in y-direction 



N number of degrees of freedom 



n number of transformations 



R boundary of spatial integration 



s directional spreading parameter 



Sj„ maximum value of s 



s dimensionless spreading parameters s/Sjj, 



U windspeed at 10 m elevation 



V tidal current vector 



V magnitude of V 



X place vector x = (x,y) 



x,y,z spatial coordinates 



A increment 



9 direction, orientation of waveniomber vector 



9j, orientation of tidal current 



9i[, mean direction 



a„ standard deviation of helicopter yaw 



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