March 1974 



With no additional icebergs reported to the 

 Ice Patrol office in early March, an additional 

 preason survey was conducted March 12-15. The 

 flight tracks and observed icebergs are shown in 

 Figure 5. The southernmost berg during this 

 survey was at 47°20'N 46°14'W with one addi- 

 tional berg south of 48°N. Twenty-nine icebergs 

 and many growlers were sighted between 48 °N 

 and 49°N; fifty-one bergs and many growlers 

 between 49 °N and 50 °N. On the basis of these 

 flights, computer ice drifts and an analysis of 

 actual and predicted pressure patterns, the first 

 bergs were estimated to drift south of 46°N by 

 March 21, thus Ice Patrol services commenced 

 that date. Ice Patrol forces were deployed to St. 

 John's, Newfoundland on March 25. Sea ice 

 conditions were normal over Davis Strait during 

 March with a slight deficit off the Labrador coast. 

 The southern edge of the pack remained between 

 47°N and 48°N through mid-March. The heavier 

 pack ice remained well offshore, and at the end 

 of the month, the southern limit extended east- 

 ward from St. John's very similar to its position 

 at the beginning of the month. Figure 6 shows 

 these sea ice conditions along with the southern- 

 most iceberg of the month at 45°36'N 43°25'W. 

 After a good reconnaissance flight by the Ice 

 Patrol aircraft on March 30, together with the 

 computer drift of the preseason iceberg survey, 

 99 icebergs were estimated to have drifted south 

 of 48 °N during the month. 



April 1974 



Good reconnaissance flights on April 3 and 4 

 located almost 100 icebergs and over 50 growlers 

 between 47 °N and 49 °N. These are shown in 

 figure 7. During the first half of April, the 

 approaches to St. John's remained open and the 

 ice edge began its seasonal northward retreat. 

 At mid-month, 421 icebergs and 111 growlers 

 were located as shown in figure 8. The tongue 

 of sea ice north of the Grand Banks area changed 

 little, if any, during the rest of the month. 

 Towards the end of April, 148 icebergs and 47 

 growlers were located in the vicinity of 48 °N 

 and east of Flemish Cap as shown in figure 9. 

 The southernmost and eastermost icebergs for the 

 month occurred on April 30 at 44°31'N 46°07'W 

 and 46°40'N 40°17'W, respectively, as shown in 

 figure 10. The southernmost was some 250 miles 

 north of its position during April of last year, 



thus indicating a surface patrol may not be 

 necessary. It was an extremely heavy month, 

 however, with an estimated 345 icebergs drifting 

 south of 48°N. The tongue of sea ice north of 

 the Grand Banks area changed little, if any, by 

 the end of the month. The edge of open pack ice 

 extended as far south as 46°15'N and as far east 

 as 47°W. 



May 1974 



On the first of May a good flight covering the 

 northern Grand Banks and Flemish Cap re- 

 vealed 72 icebergs and 31 growlers, then on the 

 fourth, a flight north of this area revealed an 

 additional 161 icebergs, 40 growlers and 115 

 radar targets. These are shown in figure 11. 

 Also on May 4, the edge of sea ice reached 

 47°N 45°40'W. By May 10, the tongue had dis- 

 appeared, leaving no sea ice south of 58 °N. 

 North of about 55 °N, however, a new excess of 

 sea ice was apparent. Flights on May 10, 12 

 and 13 (figure 12) revealed a total of 740 ice- 

 bergs, an indication that this was not going to 

 be just a heavy year, but one of the heaviest years 

 in Ice Patrol history. On May 15, the eastern- 

 most iceberg of the month was at 47°52'N 

 37°55'W as shown in figure 13. By the end of 

 the month, the eastern limits of sea ice had con- 

 tinued to decrease, however, the southern limit 

 remained in the vicinity of Baccalieu Island. 

 The southernmost berg of the month, as depicted 

 with the ice conditions in figure 14, was 130 miles 

 north of the southernmost iceberg positions dur- 

 ing the same month last year. Thus any appre- 

 hension of requiring a surface patrol was abated. 

 An estimated 446 icebergs drifted south of 48°N 

 during the month. 



June 1974 



On the first of June, 121 icebergs and 43 

 growlers were located on the northern Grand 

 Banks and Flemish Cap. Then on June 2, the 

 area southeast of Flemish Cap was investigated, 

 searching for icebergs previously reported by 

 ships. The visibility was excellent, but nothing 

 was sighted indicating that the bergs had already 

 melted. These flights are shown in figure 15. 

 Early in the month sea ice remained in Concep- 

 tion and Trinity Bays and northwest along the 

 coast approximately 60 miles offshores. The 

 easternmost iceberg of the season was in position 

 49°25'N 37°53'W on June 10. The ice condi- 



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