OCEANOGRAPHY OF THE GRAND BANKS REGION 

 OF NEWFOUNDLAND 



March 1971 — December 1972 

 Robert W. Scobie ' 



INTRODUCTION 



The iceberg- threat to North Atlantic sliipping 

 was more severe in 1972 than in any other year 

 in International Ice Patrol (IIP) history. The 

 ice season officially extended from 29 February 

 to 4 September — the longest ever. During that 

 period, a record 1587 icebergs were reported 

 south of 48°N. This surpassed the previous 

 high of 1320 icebergs sighted in 1929. In 1972 

 icebergs were reported as far east as 47°02'N, 

 36°59'W and as far south as 39°57'N, 45°06'W. 

 For the first time since 1959, conditions were 

 severe enough to require a surface patrol to 

 standby the southernmost iceberg. This duty 

 was shared by several Coast Guard cutters from 

 25 April until 25 July when icebergs were no 

 longer a threat below 43°X. 



Oceanographic Operations 



During the months of April, May. and Jiuie, 

 when the iceberg threat was greatest, three 

 oceanographic cruises were conducted to the area 

 immediately eastward of the Grand Banks of 

 Newfoundland by the USCGC EVERGREEN 

 (WAGO-295). The purpose of these cruises 

 was two-fold. First, it was to provide Com- 

 mander, International Ice Patrol (CUP) with 

 real-time oceanographic data for predicting ice- 

 berg drift in the North Atlantic Ocean. Second, 

 it was to support U.S. Coast Guard oceano- 

 graphic research i)rograms. The crew of CGC 

 EVERGREEN was augmented with a field 

 party of scientists and technicians from the 

 U.S. Coast Guard Oceano<rraphic Unit (CG 

 OCEANOU) on each of these cruises. 



Itinerary 



On 3 April the t^GC EVERGREEN departed 

 its homeport of Boston, Massachusetts on a 21- 

 day cruise wliich included a one day port call at 

 St. John's Newfoundland. The oceanograpliic 

 work conducted on this cruise consisted of 72 

 STD stations taken along 7 standard Ice Patrol 

 sections extending from A2 to A4 (fig. 1). Sev- 

 eral casts were taken at other than the desired 

 position because of locally heavy concentrations 

 of icebergs. 



During the second ciuise of 17 days, which 

 began on 5 May, 53 STD stations were occupied 

 on six standard sections from A4 to A2B. The 

 final CGC EVERGREEN cruise of the season 

 commenced on 3 June. After completing section 

 A4 and part of section A3C, a large dead-in-the- 

 water contact appeared on the radar. Proceed- 

 ing slowly through thick fog, CGC EVER- 

 (tREEN was able to identify the contact as a 

 large tabular iceberg located at 42°42'N, 49°20' 

 W. Commander International Ice Patrol then 

 ordered CGC EVERCJREEN to standby this 

 iceberg and assume full duties of surface patrol 

 vessel. Thus from 7 June until 15 June, oceano- 

 graphic work was confined to tlie area around 

 the iceberg. During this period STD casts, 

 XBT casts, and photographs of the iceberg were 

 taken. After being relieved of this responsibil- 

 ity, an abbreviated survey along 4 sections from 

 A3B to A2 was conducted. Of the 54 STD casts 

 taken during this cruise, 16 were taken near the 

 large iceberg. The CGC EVERGREEN re- 

 turned to Boston on 22 June. 



'T'.S. Coast Cuiud Orcano-jraphic T'liit, Bldg. 1.^9-E, 

 Navy Yard .\iiiif.\, Wasliinston, D.C. 20590. 



