Internal Waves Force Elevated Turbulent Mixing at Barkley Canyon. Anstey, K. J., Klymak, J. M., Mihaly, S. F., & Thomson, R. E. J. Geophys. Res. Oceans, 129(7):e2023JC020760, 2024. e2023JC020760 2023JC020760
doi  abstract   bibtex   
Submarine canyons are hot spots for topography-internal wave interactions, with elevated mixing contributing to regional water mass transport and productivity. Two velocity time series compare and contrast internal waves deep inside Barkley Canyon to a nearby site on the shelf-break slope of the Vancouver Island Continental Shelf. Elevation of internal wave energy occurs near topography, up to a factor of 10 above the slope and 100 in the canyon. All frequency bands display strong seasonal variability but weak interannual variability. Diurnal (K1) energy is sub-inertial, trapped along topography, and forced locally through barotropic motions. Both sites have high near-inertial (NI) energy linked to wind events, though fewer events are observed deep inside the canyon. At the slope site, near-inertial energy is attenuated with depth, while in the canyon it is amplified near the bottom. Freely propagating semidiurnal (M2) energy appears focused near critical shelf-break and canyon floor topography, due to local and remote baroclinic forcing. The high-frequency internal wave continuum has enhanced near-bottom energy at both sites (up to 7 × the Garrett-Munk spectrum), and inferred dissipation rates, $ɛ$, reaching 10-7 W kg-1 near topography. Dissipation is most strongly correlated with semidiurnal energy variability at both sites, with secondary contributors that are site dependent. Forcing power law fits are $ɛ∼$M20.8+ \varepsilon \sim M_2\textasciicircum0.8+\ SubK10.6 \\textSub_K_1\textasciicircum0.6\ on the slope, and $ɛ∼$M21.5+ \varepsilon \sim M_2\textasciicircum1.5+\ NI0.2 in the canyon. There is also a build-up of ``shoulder'' energy (PSh) near the buoyancy frequency, with a power law fit to dissipation of PSh $∼$ $ɛ$0.3 at both sites.p̌hantom\
@Article{	  ansteyetal24,
  Title		= {Internal {{Waves Force Elevated Turbulent Mixing}} at
		  {{Barkley Canyon}}},
  Author	= {Anstey, Kurtis J. and Klymak, Jody M. and Mihaly, Steven
		  F. and Thomson, Richard E.},
  Year		= {2024},
  Journal	= {J. Geophys. Res. Oceans},
  Volume	= {129},
  Number	= {7},
  Pages		= {e2023JC020760},
  DOI		= {10.1029/2023JC020760},
  URLDate	= {2024-11-21},
  Abstract	= {Submarine canyons are hot spots for topography-internal
		  wave interactions, with elevated mixing contributing to
		  regional water mass transport and productivity. Two
		  velocity time series compare and contrast internal waves
		  deep inside Barkley Canyon to a nearby site on the
		  shelf-break slope of the Vancouver Island Continental
		  Shelf. Elevation of internal wave energy occurs near
		  topography, up to a factor of 10 above the slope and 100 in
		  the canyon. All frequency bands display strong seasonal
		  variability but weak interannual variability. Diurnal (K1)
		  energy is sub-inertial, trapped along topography, and
		  forced locally through barotropic motions. Both sites have
		  high near-inertial (NI) energy linked to wind events,
		  though fewer events are observed deep inside the canyon. At
		  the slope site, near-inertial energy is attenuated with
		  depth, while in the canyon it is amplified near the bottom.
		  Freely propagating semidiurnal (M2) energy appears focused
		  near critical shelf-break and canyon floor topography, due
		  to local and remote baroclinic forcing. The high-frequency
		  internal wave continuum has enhanced near-bottom energy at
		  both sites (up to 7 {\texttimes} the Garrett-Munk
		  spectrum), and inferred dissipation rates, {$\varepsilon$},
		  reaching 10-7 W kg-1 near topography. Dissipation is most
		  strongly correlated with semidiurnal energy variability at
		  both sites, with secondary contributors that are site
		  dependent. Forcing power law fits are
		  {$\varepsilon\sim$}M20.8+ {\textbackslash}varepsilon
		  {\textbackslash}sim
		  M\_2{\textasciicircum}0.8+{\textbackslash} SubK10.6
		  \{{\textbackslash}textSub\_K\_1{\textasciicircum}0.6{\textbackslash}
		  on the slope, and {$\varepsilon\sim$}M21.5+
		  {\textbackslash}varepsilon {\textbackslash}sim
		  M\_2{\textasciicircum}1.5+{\textbackslash} NI0.2 in the
		  canyon. There is also a build-up of ``shoulder'' energy
		  (PSh) near the buoyancy frequency, with a power law fit to
		  dissipation of PSh {$\sim$} {$\varepsilon$}0.3 at both sites.\vphantom\}},
  copyright	= {All rights reserved},
  langid	= {english},
  Keywords	= {Barkley Canyon,continental slope,internal
		  waves,jmkrefereed,mixing,submarine canyon,turbulent
		  dissipation},
  Note		= {e2023JC020760 2023JC020760},
  File		= {/Users/jklymak/Zotero/storage/X3Y2HVY6/Anstey et al. -
		  2024 - Internal Waves Force Elevated Turbulent Mixing at
		  Barkley
		  Canyon.pdf;/Users/jklymak/Zotero/storage/6ZULD53Q/2023JC020760.html}
}

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