A water mass transported by the Continental Slope Current from the North Atlantic into the Nordic Seas. It has typical property values in the Rockall Channel region of the Greenland–Scotland Ridge of 9.5–10.5°C and 35.35–35.45. This makes it the saltiest and warmest of the waters exchanged over the Ridge. The origins of the high salinity are to date a matter of debate, with some postulating a Mediterranean source, and others conjecturing that the high salinity is acquired by a combination of winter cooling at constant temperature (i.e. sea ice formation and the resultant brine release) for intermediate depths and evaporation and advection from southern areas for near–surface layers.