whilestillwithinthe Ice Patrol opera- 

 tions area. The early failure of 9876 

 could have been caused by sea ice. 

 It was deployed into an area with 2/ 

 10 sea ice cover, and remained 

 within or near the ice edge for its 5- 

 day drift. The drogue sensor indi- 

 cated that the drogue was connected 

 throughout its 5 operational days. 



During the 5 days for which drift data 

 are available, 9876 drifted eastward 

 between the 200-m and 1000-m 

 isobaths (Figure B-2a). Tempera- 

 ture was fairly constant at about - 

 1.6°C. Speeds varied between 10 

 crrVs and 70 cm/s and often changed 

 abruptly (Figure B-2b). 



Bouy 4565 



Buoy 4565 was deployed at 1523Z 

 on 29 March (88) at 50-43N, 50- 

 40W. It remained within the Ice 

 Patrol operations area for 97 days, 

 drifting east of 39W on 4 July (185) 

 (Figure B-3a). The drogue sensor 

 indicated that the drogue was con- 

 nected while in the Ice Patrol area, 

 disconnecting on 19 September 

 (262). The buoy stopped transmit- 

 ting on 28 January 1990. 



After deployment, buoy 4565 drifted 

 southeastward off the shelf and 

 continued its southeastward drift until 

 20 April (110). The eastward com- 

 ponent of this drift could have been 

 caused by wind-driven ice drift. It 

 was deployed in a region of 2/1 sea 

 ice cover. Until mid April it was near 

 or within the sea ice edge, typically 

 in not more than 2/1 sea ice cover. 

 The eastward drift was sufficient to 

 drive this buoy out of the Labrador 

 Current. Following a cyclonic loop 

 between days 1 1 1 and 1 29, the buoy 

 drifted northeastward and then 

 northward. From day 91 to day 130 

 the temperature increased from 0°C 

 to6.4'='C(0.16°C/day). Speeds were 



1 to 20 cm/s from days 1 29 to 1 39, 

 then slowed to less than 10 cnVs 

 untilday 1 50 when the speed started 

 to increase, reaching 90 cm/s on 

 day 158 (Figure B-3b). Tempera- 

 tures also started to increase on day 

 150, indicating that the buoy en- 

 tered the North Atlantic Current. 

 Between day 150 and 185, tem- 

 peratures increased from 6°C to 

 14°C. Betweendays160and170, 

 during which speeds varied between 

 45 and 80 cm/s and temperatures 

 were between 9°C and 10.8°C, the 

 buoy made an anticyclonic loop. 



Buoy 9879 



Buoy 9879 was deployed at 1515Z 

 on 8 April 1989 (98) at 52-03N, 49- 

 59W. It remained within the Ice 

 Patrol operations area for 41 days, 

 departing to the north on 19 May 

 (139) (Figure B-4a). The drogue 

 sensor indicated that the drogue was 

 never connected. It beached in 

 Macrihanish, Scotland around 15 

 April 1990 (105). 



Buoy 9879 initially drifted southward at 

 18to30cnVseastofthe 1 000-misobath. 

 Mer 4 days it turned eastward and 

 slightly inaeased speed (25 to 35 crrVs) 

 t)efore slowing (1 to 10 cnrVs) between 

 days 110 and 116 when its eastward 

 drift was interrupted (Rgure B-4b). Its 

 eastward drift out of the Labrador Cur- 

 rent suggests that its drogue was not 

 connected, and it was rTX)re influenced 

 by wind-driven surface currents. From 

 day 1 1 7 until 1 39, the buoy resumed its 

 drift eastward and then northward out of 

 Ice Patrol's area. 



Temperatureswereuniform(about3°C) 

 until day 121 when the buoy turned 

 northward and temperatures increased 

 approximately 3°C and became more 

 variable. 



Buoy 4537 



Buoy 4537 was deployed at 1906Z 

 on 10 April (100) at 47-OON, 47- 

 20W. It failed within the Ice Patrol 

 operations area on 14 October(287). 

 The drogue sensor indicated that 

 the drogue was connected 

 throughout its operational period. 



Buoy 4537 (Figure B-5a) drifted 

 southward atongthelOOO-mcontour 

 at speeds of 9 to 25 cm/s until day 

 121 when it moved offshore, possi- 

 bly under the influence of a warm- 

 core eddy. Sea surface temperature 

 charts produced by the Canadian 

 Meteorological and Oceanographic 

 Centre (METOC) in Halifax show 

 the existence of such a warm-core 

 eddy during the same period. It 

 then drifted southward into the North 

 Atlantic Current which transported it 

 to the northeast. The temperature 

 record shows an increase on day 

 129 (FigureB-5b) shortly after the 

 buoy left the shelf. Between days 

 133 and 161 the buoy appeared to 

 be in a rapidly advecting cyclonic 

 eddy. During this period (days 132 

 to 154), the temperature increased 

 from 1°C to 12°C. Then, between 

 days 1 80 and 226 the buoy made 1 1 

 cyclonic loops (20 km - 60 km di- 

 ameter), and during this time the 

 temperature ranged from 9°C to 

 15.8°C. It then travelled to the 

 southwest between days 226 and 

 250, contrary to the mean direction 

 of the North Atlantic Current. Speeds 

 during this period ranged from 1 to 

 31 cnVs,decreasingtowardday250. 

 It then reversed direction and trav- 

 elled to the northeast and then 

 northwest at increasing speeds (up 

 to 110 

 cm/s). 



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