Evolution and Transformation of the North Icelandic Irminger Current Along the North Iceland Shelf

The North Icelandic Irminger Current (NIIC) flowing northward through Denmark Strait is the main source of salt and heat to north Iceland shelf. We quantify its along-stream evolution using first high-resolution hydrographic/velocity survey that spans entire shelf along with historical hydrographic measurements as well data from satellites surface drifters. NIIC generally follows break. Portions flow recirculate near Kolbeinsey Ridge. current's volume transport diminishes northeast before it merges Atlantic Water inflow east Iceland. properties current are modified pathway, predominantly because lateral mixing cold, fresh offshore waters rather than air-sea interaction. Progressing eastward, cools freshens by approximately 0.3°C 0.02–0.03 g kg−1 per 100 km, respectively, in both summer winter. Dense-water formation on limited, occurring only sporadically record. this locally formed water match lighter portion Jet (NIJ), which emerges transports dense toward Strait. In region Iceland, prone baroclinic instability. Enhanced eddy kinetic energy over steep slope there suggests a dynamical link between eddies shed NIJ previously hypothesized. Thus, while rarely supplies directly, may be dynamically important for overturning circulation Nordic Seas.