Table I— VOLUME TRANSPORTS THROUGH STANDARD SECTIONS A2 AND A3 



Wilson (1960) reviewed all determinations of 

 Cd and found that 0.0024 and 0.0015 were the 

 values applicable to strong winds (>15 kns) and 

 light winds (<15 kns), respectively. Determi- 

 nation of the wind stress on the sea surface at 

 A3 gave a value of 2.65 dynes/cm=. At A2 the 

 corresponding value was only 0.13 dynes/cm-, 

 or less than 1/20 of the value at A3. 



Baroclinic volume transports through sections 

 A2 and A3 were computed based on geostrophic 

 considerations (Table I). At A2, the total south- 

 ward transport varied less than 15% between 

 any of the three occupations. A comparison of 

 the vertical sections of density, temperature, and 

 salinity during the three occupations of A3 (figs. 

 7-10) showed very little change at any depth. 

 Between the first and second occupations, tliere 

 was a slight increase (0.32 sverdrups) of the 

 total southward transport, but there was a de- 

 crease in the cold core transport (the cold core 

 is defined as Labrador Current water less than 

 2°Cand34.3Voo). 



At section A3, the total southward transport 

 decreased by more than 53% from 6.94 to 3.29 

 sverdrups between the 20 and 24 May occupa- 

 tions. There was a corresponding decrease in 

 the volume transport of the cold core. Between 

 the second and third occupations, the volume 

 transport increased by 42% to 5.65 sverdrups. 

 Between the first and second occupations, the 

 27.0 and 27.5 isopycnals near the shelf break 

 moved upward 58 meters in 94.5 hours (20-24 

 May) in response to the offshore mo\ement of 

 the surface water layer (fig. 11). About 60 miles 



east of the shelf break, there was a correspond- 

 ing depression of the 27.5 isopycnal. The evi- 

 dence of upwelling was also apparent in both 

 temperature and salinity vertical sections near 

 the continental slope (figs. 12-14). 



Yoshida (1955) has considered upwelling as- 

 sociated with winds of a few days duration. He 

 considered a two-layer ocean with a homogeneous 

 upper layer of depth h, and the density differ- 

 ence between the two layers of Ap. A straight 

 coast, or in this case the boundary formed by the 

 eastern edge of the continental shelf, was defined 

 by x = 0. It was also assumed that conditions 

 did not vary in the y-direction. For uniform 

 wind stress, the vertical velocity at the base of 

 the surface layer becomes: 



W-„ = 



-k 



-Tje"^ 



where: W-h= Vertical velocity (cm/s) 



Ty= Surface wind stress (dynes/ 



cm^) 

 p= Density of water (g/cm^) 

 f=CorioIis parameter (s-') 



^=^°^^'"'^*(ihi77)V2 (cm-) 



g= Gravitational acceleration 



(cm/s=). 



Smith (1968) stated that for mid-latitudes, the 

 constant k can be defined by : 



50kmas— ^- 

 k 



where : 50 kilometers is the characteristic 

 width for upwelling. 



8 



