immediately be determined, was threatening traffic on the pre- 

 scribed route, so on 26 April United States-European traffic was 

 shifted to extrasoutherly track A. The last few days of the month 

 were more favorable for ice scouting, both by planes and surface 

 craft, and a series of intensive and extensive searches were begun 

 in the areas in which the southern and southeasternmost ice had 

 been reported. 



It is estimated that 98 bergs entered the area south of 48° N., 

 during April. The distribution of bergs and field ice during the 

 month of April is shown graphically in figure 43. 



May 



The areas southwest and south of the Tail of the Banks and be- 

 tween latitudes 43° N., and 45° N., from 43° W., to 46° W., were 

 scouted out during the last few days in April and the first few days 

 in May. Apparently the bergs that had been reported in these 

 areas had disintegrated. Accordingly, United States-European 

 traffic was returned to track B on 4 May. The berg drifts con- 

 tinued southward along the eastern edge of the Grand Banks but 

 in addition a great many were drifting eastward south of the 45th 

 parallel and many were distributed north of 47° N., from the east- 

 ern edge of the Grand Banks eastward to 43° W. Toward the end 

 of the month bergs were reported in unusually easterly positions, 

 the easternmost of these being reported on the 28th at 42° 57' N., 

 40°35' W. The original report of the easternmost berg described 

 it as a small berg only 6 feet above water and it is presumed that 

 it did not long survive the relatively high temperatures of the 

 water in its vicinity. On the 26th bergs were reported at 42° 12' 

 N., 52°40' W., and 41°46' N., 53°07' W. A search of this area, 

 southwest of the Grand Banks, was made by the surface patrol 

 vessel on the 28th and 29th but the bergs were not relocated. This 

 period saw the widest spread in the distribution of bergs. 



The advancing season and the increase in surface temperature 

 resulted in a rapid retreat northward of the southern limits of 

 the field ice. By the middle of the month only a few patches re- 

 mained south of the 50th parallel and by the end of the month 

 the southern limits of the field ice stood at about 52° 40' N., with 

 navigation possible through the Strait of Belle Isle. 



The largest number of bergs drifting south of the 48th parallel 

 for any month during the season occurred during May. The num- 

 ber is estimated at 168 and their distribution is shown graphically 

 in figure 44. 



June 



This month was characterized by a marked reduction in the 

 number of bergs entering the area and by marked easterly drifts 

 of bergs between the 43d and 45th parallels. Very few bergs en- 



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