Abstract
Closely spaced CTD stations showed elevated oxygen within Monterey
Submarine Canyon. Anomalously high (2 to 5 umol kg -1)
dissolved oxygen was found between 600-1100m in the O2
minimum, co-located with a turbulence hotspot caused by convergence of
upcanyon, semidiurnal internal tidal energy flux. Furthermore, the
oxygen anomaly extended > 10-km downcanyon at the same
depth and isopycnals of a previously identified intrusion predicted from
buoyancy conservation. We show that dissolved oxygen and fine suspended
particles act as independent tracers to 1) validate previous
microstructure observations of intense turbulence extending
~> 400 mab at the canyon hotspot, and 2)
track boundary-interior exchange driven by mixing in the form of
isopyncal-spreading of anomalies away from a near-boundary source. This
study demonstrates the use of oxygen, commonly measured with shipboard
profiling, as a tool for tracking mixing and lateral dispersal.