measurements was determined prior to the beginning of the 1957 

 season. In view of the foregoing, the same curve, with a constant 

 adjustment of 0.006°/ oo , to accommodate the above difference 

 between titration and bridge measurements, was used in 1958. 

 In spite of this, however, there still appears to be a discrepancy 

 between the Evergreen salinities and those determined by the 

 Woods Hole Oceanographic Institution if one may judge by com- 

 paring the potential temperature-salinity relationship of the deeper 

 samples beneath the Atlantic Current south of the Grand Banks 

 in May 1958, with that found by WHOI in the deep water west 

 of Bermuda. Aside from this unsolved question of perhaps 0.04°/ oo 

 discrepancy in the absolute values of salinity, we may state that 

 the precision of the observed salinities listed in the Table of 

 Oceanographic Data is ± 0.005°/ oo although the accuracy is only 

 that of silver nitrate titration. 



In the field measurements the bridge was standardized with 

 water from an oilsealed carboy of actual sea water. At least twice 

 during each salinity run, Copenhagen standard water of the batch 

 P23 was measured as an unknown. At the end of each survey 

 these measurements were used to determine whether a correction 

 to the salinities for the survey was required. The corrections thus 

 indicated were as follows: first survey — 0.00 2 °/ oo ; second 

 survey — 0.00!°/ oo ; third survey +0.00 3 °/ 00 ; postseason cruise 

 — 0.00 6 % , . The corrections for the season's surveys were neg- 

 ligible and for these no corrections were applied to the values 

 tabulated. The correction of — 0.00 6 °/ oo has been applied to the 

 salinities for the postseason cruise. 



Figures 19 through 22 show, in chronological order, the dy- 

 namic topography found during the three surveys made during 

 the season and during the occupation of the Bonavista triangle 

 on the postseason cruise. Figure 23 shows the monthly mean 

 barometric pressure at seal level in the North Atlantic for the 

 months of January, February, and March 1958 in comparison 

 with the normal 2 barometric pressure distribution for these 

 months. It will be seen that throughout this protracted period 

 the Azores high, which usually controls the North Atlantic area, 

 was very weak and displaced toward the southeast and that the 

 atmospheric circulation was dominated by a vigorous low in the 

 vicinity of Newfoundland. The resulting easterly winds expe- 

 rienced along the Laborador coast, and to a lesser extent the 

 Newfoundland east coast, were expected to have a pronounced ef- 

 fect on the currents in the Grand Banks region. 



The abnormal wind pattern ended just prior to the beginning 



2 Normals are from U.S. Weather Bureau Technical Paper No. 21. Normal Weather Charts 

 for the Northern Hemisphere, Washington Oct 1952. 



33 



