of bergs on ■which to apply the pressure tendency. As the area encom- 

 passed by the bergs is vast, and as the pressui'e distribution may vary 

 considerably from the northern to the southern areas, the bergs that 

 pose a potential threat to the Grand Banks from March to July are 

 divided into two groups for ease of analysis. The first group includes 

 those bergs located between Hudson Strait entrance to Cape Dyer in 

 early November. The second group includes those bergs betweeen Cape 

 Dyer and Bylot Island, also in November. The successive monthly lo- 

 cations of the two groups of the berg crop can be assumed or estimated, 

 using available northern berg survey observations and taking into 

 account drift^ due to the current systems. 



Table 3 is a statistical summary of the effect of mean surface winds 

 correlated with the number of bergs drifting south of latitude 48° N. 

 The daily surface pressure charts were analyzed and were compared 

 to the U.S. Weather Bureau montlily sea level atmospheric charts. 

 The differences noted were due to the averaging techniques masking 

 short periods of great deviation ol:)served in the daily charts. This 

 deviation can play an important pai-t in assessing berg-crop drift as, 

 in general, from Cape Dyer south to Newfoundland, bergs can be 

 driven aground, entrapped in the many bays and indentations along 

 the coast, and not be permitted to drift free under favorable wind 

 conditions. 



The daily weather surface pressure charts, developed by the U.S. 

 Fleet Weather Facility, Argentia, Newfoundland, were also analyzed 

 to determine if surface wind conditions were such as to indicate a 

 radical change in oceanic circulation of the Labrador Sea-Grand 

 Banks area (refer to figs. 3, 5, and 6). A qualitative application of 

 wind driven oceanic circulation theories, with emphasis on the effect 

 of wind on surface current direction and mass volume transport, was 

 applied. The area investigated was the North Atlantic Ocean or the 

 subpolar gyre. The qualitative analysis compared very favorably with 

 later oceanographic investigations conducted in the Labrador Sea- 

 Grand Banks area. 



In December 1965, during a routine inspection of the weather surface 

 pressure charts of the North Atlantic, it was noted that the passage of 

 all lows was well to the southward of the normal track. This trend 

 was carefully monitored on a day-to-day basis. By the end of January 

 1966, this trend had continued in effect and it became obvious that the 

 circulation of the North Atlantic Ocean would reflect this radical 

 change in wind direction. Figures 16, 17, and 18 are the Mean Sea 

 Level pressure charts for the months of December 1965, and January 

 and Febniary 1966. An analysis of tliese charts will provide a more 

 pertinent evaluation on how wind stresses over the sea surface could 

 affect a large change from the normal oceanographic regime. 



16 



