using data from stations 9537 — 9538 and sta- 

 tions 9544 — 9545. The average speeds of 

 drogues 3 and 4 also agreed satisfactorily with 

 the computed geostrophic currents. 



Figure 70 is a progressive wind vector dia- 

 gram based upon observations taken during 

 the drogue study. The wind maintained a rel- 

 atively steady direction with a varying speed. 

 After 24 hours the net transport caused by 

 the wind stress should have manifested itself 

 through the shallow mixed layer. This trans- 

 port should have been in the northeast direc- 

 tion or acting in the direction opposite to the 

 velocity indicated by each drogue. No effect 

 such as this was observed in the drogue data. 

 Excepting drogues 3 and 4, each drogue veloc- 

 ity was greater than the corresponding calcu- 

 lated velocity. 



Perhaps the most interesting result obtained 

 from the three serial occupations of the Stand- 

 ard Section 3 is an estimate for the accelera- 

 tions occurring to the water. Using the 

 computed geostrophic velocities from Table 12 

 and the times of occupation from the station 

 listing at the end of this report, numerical 

 values for the accelerations may be determined. 

 These accelerations in some instances may 

 have a magnitude equal to the Coriolis force. 

 This contradicts one of the basic assumptions 

 in the method used to compute velocities from 

 density information. This indicates, if these 

 values for accelerations were routinely ob- 

 served, a different numerical procedure must 

 be used to compute velocities. It is easy to use 

 the drogue speed data to compute accelera- 

 tions. They also show values that are larger 

 than the Coriolis force, leading to the same 

 conclusion reached above. 



MEAN TEMPERATURE-SALINITY 

 CURVES 



Hawley and Soule (1940) stated that the 

 tempei'ature-salinity curves for the stations 

 occupied in the Grand Banks region fell into 

 three distinct groups. The warm water group 

 had the characteristics of the North Atlantic 

 Current Water and the colder water stations 

 fell into two correlation groups instead of 

 being scattered. They further stated that the 

 width of the area composed of Mixed Water 

 between Labrador Current Water and North 



Atlantic Current Water was small at the 

 "Tail-of-the-Banks," and east of the Grand 

 Banks it widened to approximately 80 nautical 

 miles. 



Hawley, Smith, Barnes, and Soule (1941), 

 using all oceanographic data obtained from 

 1934 to 1940, computed 7-year average temper- 

 ature-salinity curves. They also stated that the 

 temperature-salinity curves for all stations fell 

 into one of the three classifications. Occasion- 

 ally the values for the upper levels would fall 

 into an adjacent group if the station happened 

 to be taken near the boundary of two water 

 types. Soule and Barnes (1950) presented an 

 average temperature-salinity curve based upon 

 data from 1934-1941. 



Carter, Challender, Cheney, and Soule 

 (1950) did not present a mean temperature- 

 salinity curve based on 1948 oceanographic 

 observations. They stated that "the transition 

 from Labrador Current Water to the typical 

 Mixed Water was normally abrupt in 1948 and 

 unusually gradual from the typical Mixed 

 Water to North Atlantic Current Water." 

 This caused many stations to be located in the 

 mixing zone causing station temperature-salin- 

 ity information to scatter from the Mixed 

 Water temperature-salinity curve to the tem- 

 perature-salinity of the North Atlantic Cur- 

 rent. Cheney and Soule (1951) presented the 

 temperature-salinity relationship using the 

 1949 data and the average values calculated 

 for 1934-1941. This same procedure was fol- 

 lowed until Bush, Murray, and Soule (1957) 

 presented the mean temperature-salinity rela- 

 tionship based upon the oceanographic data 

 collected from 1948 to 1956. They also com- 

 pared the nine year 1948-1956 mean and the 

 eight year 1934-1941 mean. Since 1956 a new 

 average value has been calculated each year 

 and the yearly observation compared to it. 

 There have been three assumptions : 



1. Labrador Current Water and North At- 

 lantic Current Water are distinct water 

 masses. 



2. These two water masses mix in suffi- 

 ciently constant proportions so that the Mixed 

 Water can be regarded as a virtual water 

 mass. 



3. The mixing zones are narrow and well 

 delineated. 



24 



