TM Wo. 327 



Vertical current gradients were generally greater at Tl than along T2, A 

 net out-channel flow below 1000 meters was noted in the southern part of the 

 Northeast Providence Channel. Similarly^ an out-channel flow was noted 

 between 600 and 1500 meters along the southern portion of T2. 



Drogues set along T3 gave the first clear indication of flow out of the 

 Tongue. At 200 and 500 meters the flow was northerly out of the Tongue, whereas 

 at 1000 meters the flow was southerly into the Tongue. 



In February 1962 a series of drogue (reference 3) data measurements were 

 made in the area of T3. In brief, these data indicated a northerly flow at 

 50 and 200 meters and a southerly flow at 5OO meters, with average speeds of 

 7.6^ 4.1, and 7-5 cm/seC; respectively. 



Vertical current gradients were quite small along T3 compared with those 

 found along Tl and T2. There was also a f low cf water into the Tongue at 200 

 and 500 meters and an outflow at 1000 meters. 



The shallow drogues set along transect h indicated that the surface currents 

 are related to some extent to tidal motion. However, mixing of the bank water 

 with Tongue water was not readily apparent. A detailed analysis of the data 

 should shed more light on this subject. 



Along T5 the flow of water was northerly or out the Tongue at all depths 

 measured. A storm from theeeast interrupted tracking for a day. The effect 

 of the wind on the surface floats was shown in the sharp westwardi displacement 

 in the drogue tracks of Papa and Uniform. 



Vertical gradients were generally greater at T5 (western part of the 

 Tongue) than at T3 (eastern part). There was a positive gradient between 500 

 and 1000 meters at T5. 



There was practically no eddy motion observed along Tl except for the 

 first 36 hours of tracking drogue Victor (10 meters). This motion (figure 3) 

 was probably due to a combination of the winds and tides. 



Eddy motion was particularly noticeable along T2 at depths of 600 meters 

 and 1500 meters. The sense of rotation of these eddies was opposite to that 

 expected, if the flow patterns at Tl were representative of actual condi- 

 tions. Moreover, if water entering the Northeast Providence Channel courses 

 southward (as indicated in figures 3, h, 5), then an anticyclonic eddy would 

 be expected at T2, due to the effect of the bounding bank, rather than the 

 cyclonic eddies shown in figures 7 an<3. 8. 



Eddy motion was not observed at T3^ but a marked reversal in current 

 direction was noted at 200 meters and 500- meters. At 1000 meters, the net 

 flow was southerly. 



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