Mixing at 152W: a moored array at the shelf break of the Canada Basin

In this work we examine indirect mixing measurements across an array of six moorings that spanned the shelfbreak at 152W between 2002 and 2004. Our preliminary findings suggest the following:

• The shelf break region is important for water mass transformation, with lower halocline waters being subject to low Richardson numbers close to topography. Evidence suggests the lower halocline water mass is strongly modified via diapycnal mixing processes at the topographic boundary.
• Mixing is likely enhanced during wind driven downwelling events, which episodically lower the Richardson number across the array.
• Near-inertial wave generation is relatively intensified on the shelf compared to offshore.
• An (incomplete) 10 year timeseries on the shelf break suggests a general weakening of near inertial energy, in contrast to predictions of enhanced NIW energy in the Arctic as sea ice coverage is reduced.