between the approximate period March 15 to July 1. Bergs both 

 north and south of the location of the berg potential can be considered 

 ineffectives for the most part. Those southerly located bergs '>\dll 

 ordinarily keep drifting south, eluding the advancing formations of 

 protective pack ice and freezing waters as winter arrives. Unless 

 such a berg is very large, it stands little chance of making it to the 

 Grand Banks as deterioration is continually in progress. 



7. The variations of the period known as the Grand Banks iceberg 

 season and the variations of the severity of iceberg seasons are 

 undoubtedly due to the annual variations of the location and extent 

 of the berg potential upstream at a given time before the season and 

 the winter and spring variations of local meteorological and ocean- 

 ographic conditions and their effect on the berg supply. 



Combining the conclusions from table III with factors discussed 

 previously, the location of the berg potential for the coming year can 

 be roughly estimated. Aerial reconnaissance can then be planned 

 to cover the predicted area with sufficient overlap to enable determina- 

 tion of the location and extent of the berg potential for the coming 

 year. It is assumed that the leading edge of the group will usually 

 be rather obvious, but the northern limit will be less obvious depend- 

 ing on the forecast average berg drift rate in the progression down- 

 stream. As these northern flight results are supplemented by 

 information obtained from aerial reconnaissance prior to and during 

 the ice season on the Grand Banks and upstream as practicable, 

 additional facts will become known. 



Berg counts were made in esLviy November of 1961 in Baffin Bay, 

 Davis Strait, Hudson Strait, and the coastal waters of northern 

 Labrador by the Canadian Department of Transport during their 

 annual ice reconnaissance flights in this area. About 800 bergs were 

 located near the entrance of Hudson Strait and Frobisher Bay; 150 

 from Cape St. David to Cape Dyer, Baffin Island; and 1,000 from 

 Cape Dyer to Cape Christian, Baffin Island. There were very few 

 bergs south of Cape Chidley. Combined with the above information, 

 subsequent ice observation flights by U.wS. Coast Guard Air Detach- 

 ment, Argentia, Newfoundland, prior to and during the 1962 Ice 

 Patrol enabled the following determinations: 



1. The average drift rate of bergs from Cape Chidley, Labrador, 

 to the Grand Banks during the period November 1961 to March 1962 

 was 7.5 miles per day. 



2. The traveltime of bergs from Cape Chidley to the Grand Banks 

 was 4 months. 



3. Bergs north of Frobisher Bay in early November 1961 drifted 

 at an estimated average rate of 5.8 miles per day and were not able 

 to arrive at the Grand Banks before June 1962. 



4. Bergs north of Cape Dyer were not a factor in the 1962 ice season. 



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