meander pattern centered around 69° W. In combination, the warm-core 

 ring and the large cyclonic, meander/ ring form a perturbation in the 

 stream path of over 300 km. This pattern, with a high pressure cell (warm- 

 core ring) to the poleward side of a mean jet and a cyclonic cell (cyclonic 

 eddy) to the equatorward side of the jet, is similar to blocking patterns 

 which are common in the atmospheric jet stream. These large, long-lived 

 perturbations to the path of the Gulf Stream are just upstream of the New 

 England Seamounts (open triangles). Again this is reminiscent of the 

 atmospheric case in which blocking situations are often tied closely to 

 topographic features. The presence of large meanders and flow down the 

 axis of the seamounts, depicted in the schematic (35-1), is fairly common in 

 the Gulf Stream (Richardson, 1981). 



The meander pattern observed on this day (38-2) eventually broke 

 down. The warm-core ring proceeded on to the west and was found at 

 69° W in June (Gordon et al., 1982). It is not known whether or not the 

 cyclonic portion of the pattern separated from the stream to form a ring. A 

 full description of the events which took place in the slope water during 

 1979, based on thermal infrared data, can be found in Fitzgerald and 

 Chamberlin (1981). 



Acknowledgments 



The author would like to thank Howard Gordon, Otis Brown, and 

 Robert Evans for comments concerning these images; and particularly, 

 Jim Brown for actually bringing up the 8 May image on a display system 

 and checking the returns on the low-pigment waters on the shelf 



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39 



