On the vertical structure of deep ocean subinertial variability

Toole, J. M., Musgrave, R. C., Fine, E. C., Steinberg, J. M., & Krishfield, R. A., 2023. On the vertical structure of deep ocean subinertial variability. Journal of Physical Oceanography.   https://doi.org/10.1175/JPO-D-23-0011.1

The vertical structure of subinertial variability is examined using full-depth horizontal velocity and vertical isopycnal displacement observations derived from the Ocean Observatory Initiative (OOI), contrasted with moored observations on Line W in the Gulf Stream.  Observed structures are compared to theoretical mode profiles for flat, sloping and so-called rough-bottom solutions.  The map shows the locations of the four OOI Global Site moored arrays and of Line W moorings #5 and #6 where colors indicate the logarithm (base 10) of the bathymetric slope on 100 km scale calculated from ETOPO-2 (NOAA National Geophysical Data Center, 2006).  Regions with steeply sloping bottom are shown in red, flatter regions are colored blue/green.  Looking across the observations, no universal vertical structure is found that characterizes the subinertial variability at the five sites examined; regional bathymetry, stratification, baroclinicity, nonlinearity and the forcing (both local and remote) likely all play a role in shaping the vertical structure of the subinertial variability in individual ocean regions.  (Image provided by John Toole)