2. Bergs north of Cape Chidley in early March are not likely to be 

 a factor in the Grand Banks ice season unless: (a) winds and current 

 are abnormally favorable for drift to the Grand Banks during March- 

 June; (b) the climate is abnormally cold; (c) sea temperatures on 

 the Grand Banks and northward are abnormally cold in June and 

 July. 



3. About -to percent of those bergs located in or near the current 

 system between 58° N. and Cape Dyer including Hudson Strait and 

 Frobisher Bay entrance to 66° W. in early December can be expected 

 to drift south of 48° N. during the coming ice season. For 1964 the 

 estimate was over 50 percent, but it is pointed out that meteorological 

 and oceanographic conditions were believed more favorable than 

 normal for berg drift south and survival. About 20 percent of the 

 bergs in the Baffinland Current from Cape Dyer to Cape Christian 

 in early December will normally survive to south of 48° N. the next 

 spring. For 1964 the estimate was about 25 percent. 



4. On the basis of the average daily drift rates determined for the 

 1964 berg crop and prevailing winds, it is estimated that berg groups 

 normally advance toward the Grand Banks during the winter and 

 early spring at 9 miles per day. The overall drift rates of the first 

 three groups studied were remarkably similar, 8.2, 9.3 and 9.2 miles 

 per day respectively from 4 December 1963 to time of arrival on the 

 Grand Banks. The group drift rates are really avemge daily rates 

 of advance along the current system axis toward the Grand Banks 

 and are likely to include grounding periods. It should also be made 

 clear that groups cannot normally be expected to remain as a whole 

 distinctive group enroute from Baffin Island to the Grand Banks. 

 Bergs form groups mainly because of the existence of shoal spurs 

 that extend well offshore and collect bergs. Eventually, when mete- 

 orological conditions are right, the collected bergs will move out into 

 the deeper waters of the current system as a group. There is con- 

 siderable dispersal of groups and also tendencies toward regrouping 

 during their journey. A minority of bergs closer ashore than others 

 may be trapped longer and get left behind to join another group. 

 Another minority farther offshore may have continued to travel to 

 catch up with another group while the remainder of the group be- 

 comes stranded. However, if observations from aerial surveys are 

 analyzed and correlated with influential factors, the group majority 

 can usually be identified and traced. Tlie second and third groups 

 moved faster than the first group because they were located farther 

 offshore during the 4 December survey and managed to spend slightly 

 less time aground. The average drift rates of individual bergs for 

 various perio<ls of time in various locations, as listed in table VI, 

 are very revealing. It must be kept in mind that the individual bergs 

 studied were all large bergs and presumably spent much more time 



78 



