height. Spectra were computed for all 519 gridpoints over the North Atlantic 

 Ocean at locations shown in Figure 1 . 



The gridpoint numbers and locations for which complete spectral data 

 were printed out at each forecast time were as follows: number 20, corres- 

 ponding most nearly to the location of OWS A; number 36, corresponding to 

 OWS I; number 72, OWS J; number 142, OWS K; and numbers 229, 230, 259, 

 and 260 corresponding to the four nearest gridpoints to Argus Island (located 

 approximately 25 miles southwest of Bermuda). The locations of all these 

 gridpoints, together with the locations of the OWS stations and Argus Island, 

 used in the evaluation, are also shown in Figure 1.. 



To evaluate the New York University wave-spectra data obtained by 

 automated methods, wave meter records were acquired for four OWS locations, 

 Weather Adviser at stations I and J, Weather Reporter at stations J and K, 

 and FRANCE II at station A and K, plus the wave staff records from Argus 

 Island. The wave-spectra data chosen for evaluation were those for three 

 days in December 1966, for two days in February 1967, and for three days 

 in March 1967. These three periods of data were chosen because an examina- 

 tion of the synoptic surface weather charts showed considerable storm activity 

 which should be representative of adverse wave conditions in the eastern North 

 Atlantic. A description of the synoptic weather conditions for each of the 

 periods is given in the Appendix. Figures A-l, A-2, and A-3 of the Appendix 

 show the surface synoptic weather charts as analyzed by the National Meteorological 

 Center for 0000Z 6 December 1966, 0000Z 28 February 1967, and 0000Z 6 March 

 1967, which correspond to the times of maximum wave heights during each of the 

 three periods of data. Table I shows the observed weather and the wave heights 

 at the various OWS locations and at Argus Island. 



WAVE RECORDS 



Each of the wave meter records and the Argus Island wave staff records 

 were digitized manually to a time series which contained 800 to 1440 points at 

 time intervals of one or one and a half seconds depending on the scale of the 

 wave record. The manually read amplitudes were punched on cards and computer 

 processed to yield wave spectra containing 60 to 90 lag points over the frequency 

 range from zero to 3.14 radians per second. The method followed for obtaining 

 the spectral estimates was the same as that followed by Moskowitz, Pierson, and 

 Me hr (1962). 



The computed spectral estimates from the wave records were next plotted 

 on graph paper for lag numbers from 4 to 32, corresponding to radian frequencies 

 from 0.14 to 1.1117 radians per second. The units of energy density were shown 



