BUOY 4528 



Buoy 4528 (Figure C-21, C-22) 

 was deployed from an aircraft at 

 60-OON, 61 -43W on 1 5 August 

 (227), after the close of the 1987 

 iceberg season. Due to a data 

 formatting error, no data regard- 

 ing the status of the drogue were 

 received from the ARGOS 

 processing center. Buoy 4528 

 transmitted data throughout the 

 remainder of 1987. It entered the 

 Ice Patrol operations area on 13 

 October (286) when it crossed 

 south of 52°N. 



Buoy 4528 was deployed near 

 the 200m isobath, which it then 

 followed southward to approxi- 

 mately 55°N. Along this track, the 

 buoy's speed varied over the 

 range of 20-30 cnVs. However, 

 there was one 5-day period (1-5 

 September, 244-248) during 

 which it slowed to about 1 cm/s. 

 This occurred between Sagiek 

 and Main Banks, where the buoy 

 made a small westward excur- 

 sion. The temperature record 

 during the period, between launch 

 and 55°N, is unremarkable, with a 

 slow increase from 1 to 6°C. 



After passing south of 55°N (25 

 September, 268), 4528 followed 

 the 1 000 m isobath for the next 

 50 days, during which period it 

 moved southward then eastward 

 to a region directly north of 

 Flemish Pass. During this period, 

 the buoy's speed varied mostly 

 over the range of 20-45 cnVs, 

 with two brief periods of slower 

 motion. The temperature record 

 is remarkably constant during the 



southward motion, but when 4528 

 began its eastward motion (6 

 November, 310) the temperature 

 increased rapidly from 3.5 to 6°C. 



Buoy 4528 continued its eastward 

 motion, moving to the north of 

 Flemish Cap. Its subsequent 

 rTX)tion is complex. First it moved 

 around Flemish Cap, approxi- 

 mately following the 1 000 m 

 isobath. Then it apparently 

 became entrained in the North 

 Atlantic Current, as indicated by 

 an abrupt eastward (2 December, 

 336) then northward motion. Dur- 

 ing the first part of the period the 

 temperature increased slowly 

 from 6 to 8.5°C, then during a 28- 

 hour period (8-9 December, 342- 

 343) the temperature increased 

 by nearly 8°C. Over the same 

 period the buoy's speed in- 

 creased from 50 to 85 cm/s. This 

 indicates that the buoy had 

 entered a portion of the North 

 Atlantic Current dominated by 

 meanders and eddies. 



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