Atlantic water in the Faroe area: Sources and variability

Abstract

The inflow of Atlantic water (AW) across the GreenlandScotland Ridge and into the Nordic Seas controls both physical and biological conditions in the northeastern Atlantic through its transport of heat, salt, and other properties. The two main branches of this flow pass through the IcelandFaroe Gap and the FaroeShetland Channel, respectively. Regular monitoring along four standard sections crossing these flows provides time-series of the AW temperature and salinity variability since the late 1980s. The analysis of these series presented shows a persistent increasing trend in both temperature and salinity, modulated by smaller subdecadal oscillations. Using SUPPL.ementary data sources, the previously established link between the large-scale circulation in the North Atlantic and Atlantic inflow properties is supported. Salinity is also impacted by large changes in the Bay of Biscay source waters, and upstream airsea heat fluxes modulate temperature. Relationships between changes in transport and associated residence time, and the modifying strength of the airsea interaction and mixing, are also discussed. © 2012 International Council for the Exploration of the Sea.