We have composited and objectively analyzed historical hydrographic observations for the North Atlantic Ocean for two pentads, 1955--1959 and 1970--1974. Our purpose is the study of the temporal variability of salinity in the upper layers of the North Atlantic Ocean. Upper ocean (0--150 m) salinity differences between the two pentads exhibit statistically significant changes. The subarctic gyre east and north of Newfoundland freshened by as much as 0.5%. The northern portion of the subtropical gyre increased in salinity by as much as 0.4%, while the interior of this gyre decreased in salinity. ¿ American Geophysical Union 1989