Hourly surface meteorological data were collected at the site of the 

 wreck by the USCGC's Vigilant and Bittersweet from December 15 through Decem- 

 ber 31, 1976. Wind speeds and directions were extracted from these data and 

 are contained in Table VII-12 in Appendix VII. Hourly surface data were also 

 collected by the FAA tower at Nantucket Island airport during their operating 

 hours (0600 to 2300) and the resulting wind speeds and directions are summar- 

 ized in Table VII-13 for this same time period. Similar wind speed and 

 direction data acquired from the Nantucket Light Ship operated by USCG are 

 given in Table VII- 14. Data from the Nantucket Island airport and Light Ship 

 for other time periods are available from the National Climatic Center (NCC) , 

 Asheville, North Carolina, as a standard archive product. 



F. Godshall of NOAA's Center for Experiment Design and Data Analysis did 

 a comparative study of the winds observed at the site of the Argo Mevahant 

 and those routinely measured at the Nantucket Light Ship. He used a least 

 square vector difference technique (Godshall, et al. , 1976), by which an 

 additive direction correction and a wind speed factor was developed based on 

 vector differences that can be used for extrapolation. His findings indicate 

 that over the 15 days of data (Tables VII-12 and VII-14, appendix VII) winds 

 at the Argo Merchant site can best be estimated by subtracting 13° from the 

 directions reported by the Light Ship and multiplying the reported speeds by 

 a factor of 1.17. 



Meteorological data were acquired on all cruises in the area and, where 

 available, are given in the cruise reports contained in Appendix V. 



Using the radar altimeter aboard the Geodynamics Experimental Ocean 

 Satellite, GEOS-3, C. Parsons of Wallops Flight Center, NASA, measured signif- 

 icant wave height in meters in the vicinity of the Argo Merchant oil spill 

 from December 24 to 28. The normal scheduling of the satellite was inter- 

 rupted to accommodate the data collection along 13 ground tracks off the east 

 coast of the United States. These data were processed at the NASA Goddard 

 Space Flight Center to produce significant wave height measurements spaced 

 3.28 seconds apart in time, an increment designated as the GEOS-3 data frame. 



Figure 2-7 shows the positioning of the tracks closest to the oil spill 

 for each of the 5 days. The frame number (in italics) and significant wave 

 height are noted at regular intervals along each track. The latter given 

 quantity is the result of averaging over seven frames, a process that is 

 needed to correct for the inherent noisiness of the GEOS-3 measurement. 

 Because of the rapidity with which the storm systems moved through the area 

 during the December 24-28 period and the separation between consecutive GEOS- 

 3 ground tracks, it was not possible to generate contour maps of significant 

 wave height. 



The ground track for orbit 8832 crossed the oil spill on December 24 

 during frames 114 and 115. The variation of significant wave height near the 

 spill is shown in Figure VII-8 (appendix VII) . The dashed line is the varia- 

 tion of the three-frame average. This was used to eliminate some of the 

 noisiness of the measurement without losing all of its spatial resolution. 

 It can be seen that sea state in the vicinity of the spill was of the order 

 2.5 to 3 meters on December 24. Compared with 2 to 3 feet as observed by the 



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