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We present an analysis of current-meter, sea-level and hydrographic data collected in the Strait of Belle Isle and the northeastern Gulf of St Lawrence. From an array of moorings in the Strait from July to October 1980, we calculate a net transport into the Gulf of 0.13 × 10 6 m 3 s -1 and show that the mean and eddy fluxes of heat through the Strait represented a net loss of heat to the northeastern Gulf. The estimated rate of loss of heat is less than the long-term mean computed by Bugden (1981) but becomes comparable if adjusted for interannual changes of transport and water temperature. Moreover, the 1980 data permit the permanent tide-gauge stations in the Strait at West Ste Modeste and Savage Cove to be levelled relative to one another, thus allowing surface currents to be calculated from sea-level alone. Hence the long-term wintertime transport into the Gulf can be calculated after fractional effects on the vertical structure of the flow are considered. During an average winter it appears that advection through the Strait can account for about 35% of the Gulf Intermediate Layer. A multiple regression involving average Intermediate Layer temperatures over 9 years suggests that winter air temperature in the Gulf, representative of atmospheric cooling, and sea-level difference across the Strait, representative of advection, are equally important variables and together account for 50% of the Layer's temperature variability. Analysis of current-meter, sea-level and hydrographic data collected in 1975 supports earlier hypotheses that the strongest inflow of water with Τ < 0° C and salinity between 32 and 3 3 should occur in winter. It appears that during the 1975 field program the inflow was about 0.6 × 10 6 m 3 s -1 , which is about twice the long-term average for January to May. RÉSUMÉ Nous présentons une analyse des données de courantomètres, et de mesures du niveau de la mer et hydrographiques recueillies dans le détroit de Belle-Isle et la partie nord-est du golfe du Saint-Laurent. A partir du réseau de bouées amarrées dans le détroit de juillet à octobre 1980, nous calculons un transport net dans le golfe de 0,13 × 10 6 m 3 s -1 et ATMOSPHERE-OCEAN 26 (2) 1988, 234-251 0705-5900/88/OO0O-0234$01.25/0 © Canadian Meteorological and Océanographie Society Downloaded by [UQ Library] at 15:27 26 July 2015 Transport of Water, Heat and Salt Through the Strait of Belle Isle / 235 montrons que le flux moyen de chaleur et les mouvements thermiques de tourbillon dans le détroit ont présenté une perte nette de chaleur vers la zone nord-est du golfe en 1980. Le débit estimé de chaleur perdue est inférieur à la moyenne à long terme calculée par Bugden (1981), mais s'en approche lorsque corrigé pour les variations interannuelles de transport et de température de l'eau. De plus, les données de 1980 permettent de comparer les niveaux des stations marégraphiques permanentes de Ste-Modeste-Ouest et de Savage Cove dans le détroit, et de calculer les courants de surface à partir du seul niveau de la mer. Ainsi, on peut calculer ...

[1] We investigate the effects of surface waves on surface currents using surface drifter data from the Grand Banks and a coupled current-wave-drifter model. The theoretical basis of the study is Jenkins' theory of wave-current interaction in which wind-generated surface currents are modified by wind-wave and wave-current momentum transfers. The total surface current is the sum of the wave modified current, the Stokes drift and the tidal current. Jenkins' formulation was incorporated into the Princeton Ocean Model and applied to the Labrador Sea and the adjacent shelves. The wave energy spectrum from Wavewatch III was used to calculate the momentum transfer and the Stokes drift. A series of model experiments were conducted to simulate the drifter trajectories and examine the sensitivity of the simulations to model parameters. The results show that the Stokes drift is the dominant wave effect, which increases the surface drift speeds by 35% and veers the currents toward the wind directions. The net effect of wind-to-wave and wave-tocurrent momentum transfers reduces the surface speeds by a few percent. A statistical analysis of the model currents and drifter data shows that the inclusion of the wave effects improves the model simulations significantly. Model errors due to uncertainties in the model parameters including the eddy viscosity, wave spectrum, air drag of the drifters, and bottom friction are investigated. The model surface currents are shown to be most sensitive to the surface eddy viscosity and the wave energy spectra.