The composition of the Fram Strait freshwater outflow is investigated by comparing 10 sections of concurrent salinity, δ18O, nitrate and phosphate measurements collected between 1997 and 2011. The largest inventories of net sea ice meltwater are found in 2009, 2010 and 2011. The 2009–2011 sections are also the first to show positive fractions of sea ice meltwater at the surface near the core of the EGC. Sections from September 2009–2011 show an increased input of sea ice meltwater at the surface relative to older September sections. This suggests that more sea ice now melts back into the surface in late summer than previously. Comparison of April, July and September sections reveals seasonal variations in the inventory of positive sea ice meltwater, with maximum inventories in September sections. The time series of sections reveals a strong anti‐correlation between meteoric water and net sea ice meltwater inventories, suggesting that meteoric water and brine may be delivered to Fram Strait together from a common source. We find that the freshwater outflow at Fram Strait exhibits a similar meteoric water to net sea ice meltwater ratio as the central Arctic Ocean and Siberian shelves, suggesting that much of the sea ice meltwater and meteoric water at Fram Strait may originate from these regions. However, we also find that the ratio of meteoric water to sea ice meltwater inventories at Fram Strait is decreasing with time, due to an increased surface input of sea ice meltwater in recent sections.

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[1] The waters of Storfjorden, a fjord in southern Svalbard, were investigated in late April 2002. The temperature was at the freezing point throughout the water column; the salinity in the top 30 m was just above 34.8, then increased nearly linearly to about 35.8 at the bottom. Nutrient and oxygen concentrations showed a minimal trend all through the water column, indicating minimal decay of organic matter. Normalized dissolved inorganic carbon, f CO 2 , and CFCs increase with depth below the surface mixed layer, while pH decreases. In waters below 50 m, there was an increase in dissolved inorganic carbon, corrected for decay of organic matter using the phosphate profile, corresponding to about 9 g C m À2 relative to the surface water concentration. We suggest this excess is a result of enhanced air-sea exchange of CO 2 caused by sea ice formation. This enhancement is suggested to be a result of an efficient exchange through the surface film during the ice crystal formation and the rapid transport of the high salinity brine out of the surface layer.

The mixed layer of the ocean and the processes therein affect the ocean's biological production, the exchanges with the atmosphere, and the water modification processes important in a climate change perspective. To provide a better understanding of the variability in this system, this paper presents time series of the mixed layer properties depth, temperature, salinity, and oxygen from Ocean Weather Station M (OWSM; 66• N,2 • E) as well as spatial climatologies for the Norwegian Sea. The importance of underlying mechanisms such as atmospheric fluxes, advective signals, and dynamic control of isopycnal surfaces are addressed. In the region around OWSM in the Norwegian Atlantic Current (NwAC) the mixed layer depth varies between ∼20 m in summer and ∼300 m in winter. The depth of the wintertime mixing here is ultimately restrained by the interface between the Atlantic Water (AW) and the underlying water mass, and in general, the whole column of AW is found to be mixed during winter. In the Lofoten Basin the mean wintertime mixed layer reaches a depth of ∼600 m, while the AW fills the basin to a mean depth of ∼800 m. The temperature of the mixed layer at OWSM in general varies between 12• C in summer and 6• C in winter. Atmospheric heating controls the summer temperatures while the winter temperatures are governed by the advection of heat in the NwAC. Episodic lateral Ekman transports of coastal water facilitated by the shallow summer mixed layeris found important for the seasonal salinity cycle and freshening of the northward flowing AW. Atmospheric freshwater fluxes have no significant influence on the salinity of the AW in the area. Oxygen shows a clear annual cycle with highest values in May-June and lowest in August-September. Interannual variability of mixed layer oxygen does not appear to be linked to variations in any of the physical properties of the mixed layer.