(eddy) (C) south of the stream at 36 o 30'N,67°W. Neither feature was 

 observed at the surface, although the warm eddy is in an area of 

 relatively warm surface water. The cold ring appears in an area where 

 horizontal uniformity is expected. A similar ring was observed by 

 ART in March 1967 as it developed from a Gulf Stream eddy (The Gulf 

 Stream, Vol. 2, No. 4). Between March and November, data obtained from 

 cruises of the R/V Crawford led Puglister (personal communication) to 

 conclude that the ring observed from the aircraft in March is the same 

 ring observed by the GILLISS in November. 



The temperature gradient between the warm eddy and the surrounding 

 water is greatest at 200 meters, where its center is 6°C warmer. The 

 cold ring exhibits strong intensification with depth. There is no 

 evidence of the ring at the surface, its center is 5°C colder than 

 surrounding water at 200 meters and 7°C colder at 450 meters. 



A surface cold tongue (D) is located immediately east of the warm 

 eddy. This feature is not as evident as the previously discussed 

 features but will become more significant in phase II analyses. 



The surface pattern is less organized and has weaker gradients 

 than the deeper levels. Prior to the survey, the surface was exposed 

 to weak variable weather conditions which produced a confused sea 

 surface temperature pattern. 



Phase II indicates some major changes from conditions during phase 

 I. The northern boundary of the Gulf Stream (A) has developed a large 

 meander near 38°N,68°W. The northern boundary has a stronger tempera- 

 ture gradient on the surface, is broader at depth and slopes southward 

 as it did in phase I. The Gulf Stream boundary weakens considerably to 

 the east of 66°30'W, although it follows the 24°C isotherm just south of 

 39°N as shown by the 200- and 450-meter analyses. 



In the northeast part of the area, temperatures have increased by 

 as much as 5°C through 450 meters, and a deep flow from the east now 

 appears over this area. The warm-water advection is probably part of 

 a large meander. This influx of warm water is responsible for obscuring 

 the Gulf Stream on the surface. 



The cool feature (D) described briefly in phase I has become part 

 of a major southward intrusion of cold water. The contrast between the 

 cold intrusion and the warm water of phase I is so great that a strong 

 gradient zone has formed north of the Gulf Stream. 



The warm eddy (B) is now evident at the surface even though it 

 has cooled from 21°C to 19°C. The cold intrusion does not appear at 

 200 meters. However, a subsurface cold tongue (E) occurs east of 67°W 

 at 40°N. Although the surface (D) and subsurface (E) cold tongues appear 

 to be the same feature, they will be shown to be separate features in 

 the cross sections. 



