Mean structure and seasonality of the Norwegian Atlantic Front Current along the Mohn Ridge from repeated glider transects

Abstract

The poleward flow of Atlantic Water in the Nordic Seas forms the upper limb of the meridional overturning circulation driving an important heat transport. The Norwegian Atlantic Front Current along the Mohn Ridge between the Greenland and Norwegian Seas is characterized for the first time, using repeated sections over 14 months from autonomous underwater gliders and two research cruises. The Norwegian Atlantic Front Current follows the 2,550‐m isobath with a width of about 60 km and absolute geostrophic velocities peaking at about 0.45 m s−1. The mean transport of Atlantic Water is 4.6 ± 0.2 Sv (equivalent to temperature transport of 100 ± 6 TW). Seasonal variability was observed with an amplitude of 0.9 Sv and maximum values in the fall. The deep currents at 1,000 m explained most of this seasonal variation and were anticorrelated with time‐integrated wind stress curl over the Lofoten Basin. Part of this flow might recirculate within the Lofoten Basin, while the rest continues toward the Arctic.