Seasonality of the inshore Labrador current over the Newfoundland shelf

• The Inshore Labrador Current has different seasonality on the northern and southern Newfoundland Shelf.
• The strength of the Inshore Labrador Current is much weaker in the south than that in the north, particularly in summer.

The seasonality of the inshore Labrador Current over the Newfoundland Shelf is investigated using GLORYS (GLobal Ocean ReanalYses and Simulations, hereafter GLORYS) ocean reanalysis product and current meter data. This study finds that the seasonality of the current tends to change as it passes its bifurcation zone between 48 °30′N and 49 °30′N. In this study, the inshore Labrador Current to the north and south of the bifurcation zone are termed as the North Inshore Labrador Current (hereafter NILC) and the South Inshore Labrador Current (hereafter SILC), respectively. The NILC reaches its maximum (~2.7 Sv) in autumn, and relaxes in late winter and early spring (~1 Sv), while the SILC achieves its maximum (~1 Sv) in late autumn and early winter, and weakens in summer (~0.5 Sv). The SILC is significantly weaker than the NILC. In particular, during July and August, the northern segment of SILC is about 4 times weaker than the NILC. Change of wind patterns is found to be linked with the summer weakening of the SILC.