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Climatology of transport in the Strait of Belle Isle
  • Jean-Luc Shaw,
  • Peter S Galbraith
Jean-Luc Shaw
Fisheries and Oceans Canada

Corresponding Author:[email protected]

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Peter S Galbraith
Dept. of Fisheries and Oceans Canada
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Abstract

Seasonal and inter-annual variability of transport in the Strait of Belle Isle (SBI) were examined using 14 years of moored ADCP data. Tidal currents were largely along strait and homogeneous with depth. Transports were inwards on average, lowest (−1.0±0.8 dSv) from April to July, and highest (−4.1±1.1 dSv) from September to January. Monthly scale outflow towards the Labrador Shelf was more than twice as common between April and August than between September and March. Averaged seasonal transports were generally lower but within one standard deviation of previously published modelled values. The volume of winter Labrador Shelf water (LShW) entering the Gulf of St. Lawrence (GSL) was computed by transport integration and compares well with integrated volumes that meet LShW temperature-salinity criteria during an annual March survey of the GSL. Integrating over the whole year showed that on average 590±351 km3 enters the GSL after the March surveys are conducted, or 36±19% of the total LShW volume. Annual volumes of LShW calculated from transport suggest that inflow through the SBI accounts for 12–18% of the GSL winter surface mixed layer. Cross-strait current shear may have affected transport integration values, but SST data suggests this bias was limited to the summer. Corrections were empirically derived to account for cross strait shear in our transport calculation. The corrected time series suggests dominant summer transport may have been flowing towards the Labrador Shelf (0.4 ± 0.6 dSv).