Seasonal variability of temperature and salinity in the Labrador Current

Most of the available temperature and salinity data from the waters above the Labrador continental shelf and slope are assembled and analyzed for seasonal variations. It is first demonstrated that the horizontal temperature and salinity gradients are small in the waters over the shelf relative to the gradients across the slope where the strongest part of the Labrador Current is trapped. In the area of low horizontal gradient, a single station can represent the oceanographic conditions. This makes it possible to construct a complete series of average monthly values of temperature and salinity at various depths although no time series of data exists at one location. The series demonstrates the existence of seasonal changes in temperature and salinity at all depths down to 200 m. It is suggested that most of the seasonal changes, especially at the greater depths, are due to advection by the Labrador Current rather than to vertical processes in the immediate vicinity. A two year record from a moored current meter is presented. The temperature signal exhibits some features that seem to correlate with features in the series of averaged data.