was stronger than normal. A couple of bergs drifted east to 45° W. 

 with one reported July 4 at 49°20' N., 44°28' W., the easternmost posi- 

 tion of ice for the year. Two bergs were exceptions and remained in 

 the main branch of the Current. The first drifted south to within 100 

 miles of the Tail of the Banks and effective Track C before deteriorat- 

 ing. It was last reported as a growler on the 18th at 44°45' N., 47°30' 

 W. The second berg managed to drift south to 46°20' N., 47° 15' W. 

 before deteriorating on the 26th. 



A surprising feature of the month was the fact that bergs survived 

 longer than expected. As a result, sliips using Track F were threat- 

 ened by a few bergs throughout the month. Three main factors are 

 believed responsible for the persistence of bergs on the northern Grand 

 Banks and vicinity as follows: (1) Late June and July calm weather 

 with less resultant berg erosion; (2) Colder than normal sea tempera- 

 tures; and (3) The lateness of pack ice in Notre Dame Bay, where 

 these bergs were temporarily located until mid- June. The importance 

 of the first factor was validified by aerial sightings finding a notable 

 lack of brash and growlers around the bergs. Tlie condition of the 

 sea may be as important a factor in berg deterioration as the sea 

 water temperature, especially during periods of abnormal cyclonic 

 activity and abnormally calm periods. By the end of July, only one 

 berg, located at 48°20' N., 48° W., remained a threat to ships using 

 Track F. There were only two other bergs south of 50° N., neither 

 of which was expected to reach Track F. The supply of bergs from 

 the north was very small at this time due to the fact that the region off 

 the Labrador Coast from Belle Isle northward was dominated by 

 moderate west-southwesterly winds which drove most of the bergs 

 in this area well out to sea and warmer waters. Many of the latter 

 were driven to the east out of the south-flowing Labrador Current. 

 Ships using Track G reported many bergs in Belle Isle Strait and 

 approaches east to 50° W. until the end of the month, at which time 

 there w^as a noticable decrease of reports. Sea ice limits gradually 

 retreated from near 55° N. in early July to 58° N. by the end of the 

 month. An estimated 5 bergs drifted south of 48° N. during the 

 month. 



AUGUST 



One berg remained on the northeast slope of the Grand Banks until 

 it deteriorated about 10 August. By this date there were no known 

 offshore bergs south of 50° N. and none are believed to have crossed 

 this latitude for the rest of the month. At the end of August an esti- 

 mated 3 bergs remained south of Belle Isle with the southernmost 

 near 50° N., 50° W. Ship reports of bergs in Belle Isle Strait and 

 approaches decreased considerably from July. From mid- August on, 

 there were only a couple of ice reports from this area. The sea ice 

 limits are estimated to have receded from 58° N. to Hudson Strait 



777-824 O— 6E 



25 



