against tlioir mean dates as the circles shown in the ligure. Average 

 mean montlily rates of change were then used to extend tlie hnes in 

 each direction from tliese circled points. While the tentative normals 

 shown in figure 39 are better than those previoush' published in Bul- 

 letin 36 of this series, the remaining irregularities indicate that there 

 are still imperfections in the curves. 



Data are insufficient to determine even tentative normals for sec- 

 tions H and F,. 



Volume transport, mean temperatiu'e, minimum observed tem- 

 perature and heat transport were evaluated for 23 occupations of such 

 sections in 1959 and IS occupations in 1960, and are tabulated ])elow 

 in comparison with seasonal normal values where they are available. 

 Temperatures are given in ^C, volume transport in millions of 

 cu.m/sec. and heat transport in millions of cu.m°(Vsec. Figure 40 

 is a schematic diagram re])resenting the circulation deduced from the 

 volume transports found during the 1960 surveys and listed in the 

 table. In the fii-st survey the Labrador Current was warmer tlian 

 normal both as to mean temperature and minimum observed tem- 

 perature. Recurvature after j^assing latitude 45"^ X., reduced the 

 volume transport from greater than normal at section U to decidedly 

 below normal at section W. In the second survey very nearly normal 

 volume at section G did not suffer the usual losses and so was above 

 normal at sections F and T. Mean temperatures were near normal 

 at G and F and above normal at T. The coldest water graded from 

 colder than normal in the north to warmer than normal in the south. 



In both the third survey and postseason occupations of the 

 Bonavista triangle the volume transports appearing in figure 40 have 

 been adjusted so that the volume entering past section XW ecjuals 

 the sum of the volumes leaving across the other two sections. Con- 

 sidering this "mean triangle" the volume transport was about a 

 million cu.m/sec. above noiinal during the tliird survey and about a 

 quarter of a million above normal during the postseason cruise. 

 Minimum temperatures were about normal in botli occupations. 

 Mean temperatures, how^ever, went from near normal during the 

 third survey to about 0.9° above normal during the postseason cruise. 

 During the fourth survey, the mean temperature anomalies warmed 

 from —0.2 at section F to +0.3 at U and dropped to slightly below 

 normal at W. Volumes were below normal at F and T and above 

 normal at U and W. These changes are considered to result from 

 losses of Labrador Current water seaward and additions of warmer 

 water from the Grand Banks. 



Off Soutli Wolf Island l)oth the volume transport and mean tem- 

 perature were above normal with a resulting large heat transport. 



Section U has been occupied 56 times during 21 different years and 

 the occupation during the first survey of 1960 is the first time that a 

 ^ positive temperature has been recorded as the minimum observed 



61 



