percent small, 50 percent medium, 25 percent large) north of Cape 

 Dyer. A normal supply of bergs located in late February south of 

 Cape Chidley is about 1,100 bergs (48 percent small, 40 percent 

 medium, 12 percent large), 600 south of 56° N. and 500 north of 56° 

 N. Any evaluation of a supply must take berg size into account. 



10. Normally 40 percent of the bergs located between 58° N. and 

 Cape Dyer and 20 percent of the bergs between Cape Dyer and Cape 

 Christian in early December will drift south of 48° N. next spring. 

 Normally 35 percent of the bergs located south of Cape Chidley and 

 55 percent of the bergs located south of 56° N. in late February can 

 be expected to drift south of 48° N. 



11. The first group of bergs that arrive at the Grand Banks during 

 an ice season probably normally includes a few bergs which were 

 south of Cape Chidley in early December and large enough to survive. 

 However, normally, most of the first group arrivals are located in the 

 vicinity of Hudson Strait in early December. 



12. The relationship of sea ice to the berg problem has become very 

 apparent. The pack ice limits normally advance toward the Grand 

 Banks beginning in autumn from Baffin Bay reaching a maximum 

 quantity and maximum southern and eastern encroachment by the 

 end of winter or start of spring. During the spring the pack ice 

 limits begin to recede northward and westward from the Grand Banks. 

 The recession of the limits becomes rapid in the summer months and 

 the pack ice diminishes to a minimum in quantity and undergoes a 

 maximum retreat to the north by the end of summer. Normally, the 

 entire Labrador Sea and most of Davis Strait and Baffin Bay become 

 free of sea ice by mid-September. The cycle then reverses. The 

 advance and retreat of the Grand Banks iceberg crop is closely related 

 to the advance and retreat of the pack ice. The maximum quantity 

 and southernmost and easternmost extension of the iceberg crop on 

 the Grand Banks normally occurs a month or two following the time 

 of maximum pack ice on the Grand Banks. The recession of the berg 

 crop from the Grand Banks follows the recession of the pack ice by 

 about 3 months. The minimum quantity of icebergs south of Baffin 

 Bay is probably about mid-November or about 2 months after the 

 time of minimum pack ice. One obvious conclusion is that berg con- 

 centrations will not survive more than 3-4 months in unprotected 

 waters. Some large solid bergs may survive longer if the water 

 temperature remains cold enough, but even here deterioration must be 

 significant. The berg crop that arrives at the Grand Banks each 

 spring must have traveled most of the route in pack ice. As pack ice 

 retreats from the Grand Banks it becomes progressively more difficult 

 for later arrivals to survive to the shipping lanes. Any significant 

 departure from normal in pack ice conditions in the western portion of 

 the Labrador Sea, Davis Strait, and Baffin Bay in the summer and 



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