was cold c»re. Eight cold core 

 eddies formed in the area of the 

 Ridge. There are two possible 

 explanations for this: either the 

 cold-core eddies form more as an 

 interaction with the NAC in the 

 Newfoundland Ridge/Tail of the 

 Bank area, or they drifted 

 southeast out of the Seamount 

 area hidden by cloud cover 

 before they were reported. 



A much higher percentage of 

 Seamount eddies had an 

 unidentified generation 

 mechanism. Seven out of twelve 

 or 58% had an unknown source 

 of origin as compared with ten out 

 of 34 or 23% of the Ridge eddies. 



Labrador Current Eddies 



Perhaps one of the nnost 

 interesting results of this study is 

 the location of five cold-core 

 eddies in the area north of the 

 Gulf Stream in the normal domain 

 ofwarm-core NAC eddies. A 

 possible explanation for the 

 presence of these eddies is the 

 Labrador Current. No studies 

 have been conducted on the 

 generation of eddies by this 

 current, but Hayes and Robe 

 (1978) showed that the Labrador 

 Current extends to the bottom 

 and that the flow is variable and 

 quite often influenced by the 

 position of the NAC. If we make 

 the assumption that the bottom 

 features may cause the 

 bifurcation noted in the current's 

 flow, it is reasonable to assume 

 the varied bathymetry can also 

 cause meander and eddy 

 generation in much the same way 



82 



as it does in the NAC. Research 

 dedicated to the generation of 

 eddies by the Labrador Current is 

 necessary. 



Conclusions 



For the three-year period, this 

 study evaluated data from several 

 different sources and identified a 

 total of 46 eddies in the research 

 area. The research area was eddy 

 free only 1 5% of the study 

 period. This clearly indicates that 

 eddies are frequently in the area 

 and that they are important to the 

 dynamics of the area. The eddies 

 were concentrated near the 

 Newfoundland Seanx)unt Range 

 and the Newfoundland Ridge. 

 Except for these two areas, the 

 research area showed no sign of 

 eddy activity. This distributbn 

 suggests that the topography 

 features had an influence on the 

 formation of the eddies. This 

 indicates that, at least in some 

 areas, the NAC is influenced by 

 the bottom in the Newfoundland 

 Basin area. 



The study also suggests that the 

 Labrador Current is capable of 

 generating eddies. Five cold- 

 core eddies were found in an area 

 where they could not have been 

 generated by the NAC. 

 Kollmeyer, era/. (1965) 

 documented the existence of a 

 cold-core eddy spawned by the 

 Labrador Current and recognized 

 its importance as a cold trap for 

 icebergs. However, no 

 systematic study of Labrador 

 Current cold-core eddies has yet 



been conducted. This is a 

 subject that requires further 

 investigation. 



/In their movement, the eddies 

 followed the pattern predicted by 

 Joyce (1 984) and drifted 

 predominantly to the west. This 

 was true even for those eddies 

 that showed a considerable 

 interaction with the eastward- 

 flowing NAC. The most common 

 method of formation was pinched- 

 off meanders. Absorption back 

 into the parent current by similar 

 meanders was the most common 

 method of deterioration. 



The area of formation had no 

 apparent effect on the 

 characteristics of the eddies. 

 Those formed over the 

 Seanrx>unts displayed features 

 similar to those formed over the 

 Ridge. All were of equivalent 

 size and duration. 



The study indicates that the 

 average eddy in the southern IIP 

 operations area will be a warm 

 core eddy approximately 1 1 6 km 

 in diameter. It will forni over the 

 Seamountsoroverthe Ridge, 

 normally from a pinched-off 

 meander, and will migrate to the 

 west after formation. It will remain 

 on plot for about 42 days and will 

 normally be absorbed back into 

 the parent current. We can 

 expect to see an eddy similar to 

 the one described here in the 

 southern IIP operations area 

 about80%ofthetinne. 



