Ice in the Sea 



277 



accurately fixed by tracking numerous icebergs with the patrol ships. The main ice- 

 berg track as shown by these detailed surveys is shown in Fig. 128. An increased fre- 

 quency is to be expected along the eastern slope of the Newfoundland Banks where the 

 Labrador Current turns towards the west and its cold and weakly sahne water mixes 

 along the southern side of the current in large eddies with the warm and highly saline 

 water of the Gulf Stream. A careful study of these eddies by the Ice Patrol vessels has 



N 60 



Fig. 127. Extent and distribution of icebergs in Davis Strait and the Labrador-Sea in the 

 summer of 1928 according to the "Marion" Survey. 



been made and thereby an explanation was found for the continuing presence of ice- 

 bergs in this part of the sea, since the eddies keep the icebergs quasi-stationary 

 Occasionally individual icebergs withstand the destructive effects of the warm At- 

 lantic water and reach much further south than usual. The most southerly position 

 so far recorded was 30° 20' N. and 62° 32' W. near the Bermudas for an iceberg about 

 9 m long, 5 m broad and 1 m above the water, which was sighted by the "Baxter- 

 gate " on 5 June, 1926. 



Knowledge of iceberg drift in the polar seas of the Southern Hemisphere is very 

 scanty. The approximate northern limit of drifting icebergs is shown in Fig. 122. It 

 is, of course, far north of the northern limit of drifting ice floes since the compact 

 mass of a large iceberg can better withstand the destructive action of warm water and 

 air. It must be assumed that here also winds and currents must be the factors that 

 determine the drift of an iceberg. In some individual cases a relationship to the course 

 of low-pressure areas has been demonstrated, but in view of the irregularities of the 

 latter a strict relationship is hardly to be expected (Mecking, 1932). 



Icebergs are especially important in the Falklands area where they are sometimes 

 carried, accompanied by drift ice, far to the north in large numbers. They have been 

 sighted as far north as 42° S. and in 1906 even reached as far as 37° S. (59° W.). The 

 aperiodic variations in the occurrence of ice appear to be particularly large here. In 



