EVOLUTION OF THE LARGE-SCALE TEMPERATURE-FIELD IN THE GREENLAND SEA DURING 1988-89 FROM TOMOGRAPHIC MEASUREMENTS

The Greenland Sea Ocean Acoustic Tomography Experiment was conducted d uring 1988-89, as one component of the international Greenland Sea Pro ject, to study deep water formation and the response of the gyre to va riations in wind stress and ice cover. Six acoustic transceivers moore d in an array 200-km across transmitted to one another at four hour in tervals. Near the end of February, 1989, a sub-surface temperature max imum at several hundred meters depth disappeared over a suprisingly la rge area of the central Greenland Sea . While the water column was mod ified to about 1000 m depth over much of the gyre, the surface remaine d colder than the deeper water, contrary to what might be expected fro m simple models of convective renewal.