increased through March 1969, except at 

 300 meters where the increase lasted only 

 until February and March was slightly 

 cooler. Temperatures decreased between 

 March and April, then rose for the next 

 two months. Between June and July 

 temperatures decreased. They increased 

 in August. Little change occurred through 

 September. Subsequently temperatures 

 dropped tlirough January 1970, except for 

 a slight brief increase in November between 

 300 meters and 500 meters. Temperatures 

 then generally increased through March, 

 decreased in April, increased in May, 

 sharply decreased in June, followed by 

 increasing temperatures through September 

 1970. October showed a sharp drop, 

 followed by an increase through November. 

 By January 1971, temperatures had 

 dropped by from 1.7* C at 300 meters to 

 2.7 * C at 700 meters. By April, tempera- 

 tures had increased, and then fell through 

 July, to increase again, reaching a peak in 

 August. Temperatures then fell until 

 November, increased until January 1972, 

 and then fell until March. By June, tem- 

 peratures were much higher, and started 

 falling. This continued until November 

 (October at 700m) and fell in December. 

 Until March 1973, temperatures remained 

 within O.e" C of the December 1972 

 temperature . They fell in April. 



SALINITY 



Monthly averaged sea surface saUnity 

 values showed a seasonal variation much 

 Uke that of sea surface tempeature, but to 

 a less noticeable degree, figure 3. The 

 highest average sea surface salinity usually 

 occurred during the summer months, 

 though not always, followed by a rapid 



decrease during the early fall months. 

 A rapid increase in the surface saUnity 

 occurred during the early winter, after 

 which there was a more gradual net 

 increase toward the summer maximum. 

 However, between the rapid rise in early 

 winter, and the more gradual spring rise, 

 there was, on several occasions, a decrease. 

 The variation of sahnity with time showed 

 a greater variation at the surface as com- 

 pared to the deeper levels, showing the 

 effects at the air-sea interface. 



The monthly average salinity at 100 

 meters seemed to vary more along the 

 Unes of the deeper layers than the sur- 

 face layers. 



From 200 meters to 1000 meters the 

 variation in salinity showed a high degree 

 of similarity, with salinity decreasing as 

 one moved deeper. 



Between 1000 meters and 1500 meters, 

 the variations in salinity were similar to 

 one another, but with much less uniform- 

 ity. 



The similarity in variation of both 

 sahnity and tempeature between 700 

 and 2000 meters indicates this layer was 

 a single water mass, the North Atlantic 

 Central Water mass, as previously report- 

 ed by Rosebrook (1971). 



The similarity in variation of tempera- 

 ture and sahnity down to 1500 meters 

 again supports Rosebrook's (1971) obser- 

 vation of this being the Upper North 

 Atlantic Deep Water (Wust, 1936). 



DISSOLVED OXYGEN 



Dissolved oxygen samples were collected 

 and analyzed during two occupations of 

 Ocean Station ECHO. These were occu- 

 pation No. 49 by USCGC DUANE (14 



