Mean dynamic topography and surface circulation in the western Labrador Sea and Newfoundland offshore: satellite observations and ocean modelling

Abstract

Mean dynamic ocean topography and surface circulation for the western Labrador Sea and Newfoundland offshore are computed using a three-dimensional, high-resolution, non-linear finite-element ocean model and monthly-mean climatologies of temperature, salinity and wind stress. The agreement of the model surface topography and circulation with estimates from satellite altimetry, drifter data and hydrographic measurements, and from satellite and in situ gravity data, is good in the continental slope and deep sea but poor in some coastal and shelf regions. The surface currents from the altimetry and gravity data also compare favourably with satellite-tracked drifter data. The present study suggests that the model sea surface topography can be useful for more accurate determination of the marine geoid and therefore altimetry-derived absolute sea surface heights and geostrophic currents off Newfoundland and Labrador.

Acknowledgements

We thank Mike Foreman for an insightful discussion on this project, Jim Helbig for providing satellite-tracked drifter data, and the two anonymous reviewers for their suggestions. The project was partially funded by the Canadian Space Agency Government Research Initiative Program, the ArcticNet, the federal Program on Energy, Research and Development (PERD), and Fisheries and Oceans Canada. The MDT products were obtained from AVISO and NASA JPL.