EAST OF NORTHERN NORTHERN 
GRAND LABRADOR IRMINGER CHARLIE-GIBBS FAEROE 
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10,000 8000 6000 4000 2000 O km 
Fig. 2. Sections of salinity (X 103) versus og on a long, winding path from the Faeroe Bank 
Channel to the waters off the U.S. east coast (location shown in Figure 3). The upper section 
is drawn from a composite of historical data (Chain, 1960 and 1972; Crawford, 1960 and 1965; 
Erika Dan, 1962; Atlantis, 1964; Hudson, 1967; Knorr, 1972 and 1976) and the lower section is 
drawn from April-October 1981 TTO/NAS data. The only post-1972 data in the upper section is a 
single Knorr 1976 station in the Faeroe-Shetland Channel. The 1981 data from layers where og > 
36.9 show an average freshening of ca. 0.02 x 107-3, and since layer densities are about the 
same, there was also a cooling of ca. 0.15°C. The principal deep layers are LSW, near og = 
36.9, NEADW or Iceland-Scotland overflow water, near og = 37.0, and NWABW or Denmark Strait 
overflow water, below 37.05 in the northwest Atlantic. All displayed the u-S shift. See Swift 
(1984a) for a more thorough discussion of this figure and related results. 
and its appearance in the deep northwestern Atlantic (Livingston, Swift, and Ostlund, 1984). 
Major deep ocean responses are possible: between 1972 and 1981 the northern North Atlantic 
(north of 50°N) freshened by about 0.02°/oo and cooled by about 0.15°C below 2000 meters (Fig. 
2; see also Brewer et al., 1983, and Swift, 1984a). The deep water salinities responded to a 
freshening during the 1970's of the upper layers in the deep water mass formation regions. This 
upper-layer freshening may in turn be related to shifts in the large-scale atmospheric forcing 
over the northern North Atlantic and Greenland, Iceland, and Norwegian seas. At the present 
time the overflow transports are only approximately determined, and long-term variations in deep 
water formation rates, for example, have not yet been measured. 
