[1] Turbulence and nitrate measurements collected in the Amundsen Gulf during ice-covered conditions in fall 2007 are combined to provide mean vertical profiles of eddy diffusivity K and diffusive nitrate fluxes F. The mean diffusivity (with 95% confidence intervals) was maximum near the uppermost sampling depth (10 m) with K max = 3(2, 5) × 10 −3 m 2 s −1 and decreased exponentially to a depth of ∼50 m, below which it was roughly constant at the background value K b = 3(2, 5) × 10 −6 m 2 s −1 . The nitracline, centered around 62 m depth, was subject to an eddy diffusivity close to the background value K b and the mean diffusive nitrate flux across the nitracline was F nit = 0.5(0.3, 0.8) mmol m − 2 d − 1 . These observations are compared with other regions and the role of vertical mixing on primary production in the Amundsen Gulf is discussed.

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