Intraseasonal Cross-Shelf Variability of Hypoxia along the Newport, Oregon, Hydrographic Line

Adams, KA, Barth JA, Shearman KR, Adams KA, Barth JA, Shearman KR.  2016.  Intraseasonal Cross-Shelf Variability of Hypoxia along the Newport, Oregon, Hydrographic Line. Journal of Physical Oceanography. 46:2219ā€“2238.

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Circulation/ Dynamics, Coastal flows, Upwelling/downwelling


AbstractObservations of hypoxia, dissolved oxygen (DO) concentrations {\textless} 1.4 ml Lāˆ’1, off the central Oregon coast vary in duration and spatial extent throughout each upwelling season. Underwater glider measurements along the Newport hydrographic line (NH-Line) reveal cross-shelf DO gradients at a horizontal resolution nearly 30 times greater than previous ship-based station sampling. Two prevalent hypoxic locations are identified along the NH-Line, as is a midshelf region with less severe hypoxia north of Stonewall Bank. Intraseasonal cross-shelf variability is investigated with 10 sequential glider lines and a midshelf mooring time series during the 2011 upwelling season. The cross-sectional area of hypoxia observed in the glider lines ranges from 0 to 1.41 km2. The vertical extent of hypoxia in the water column agrees well with the bottom mixed layer height. Midshelf mooring water velocities show that cross-shelf advection cannot account for the increase in outer-shelf hypoxia observed in the glider sequ...