Overturning circulation driven by breaking internal waves in the deep ocean

• Published in: Geophysical Research Letters
• Main Authors: Nikurashin, M, Ferrari, R
• Format: Article in Journal/Newspaper
• Language: English
• Published: Amer Geophysical Union 2013
• Subjects: Earth Sciences; Oceanography; Physical Oceanography; Southern Ocean
• Online Access: https://doi.org/10.1002/grl.50542; http://ecite.utas.edu.au/86207

A global estimate of the water-mass transformation byinternal wave-driven mixing in the deep ocean is presented.The estimate is based on the energy conversion from tidaland geostrophic motions into internal waves combined witha turbulent mixing parameterization. We show that internalwave-driven mixing in the deep ocean can sustain 2030 Svof water-mass transformation. One third or more ofthis transformation is attributed to lee waves generatedby geostrophic motions flowing over rough topography,primarily in the Southern Ocean. While these results areuncertain due to many assumptions, poorly constrainedparameters and data noise that enter in the calculation, theresult that lee wave-driven mixing plays an important rolein the abyssal ocean circulation is likely robust. Theimplication is that lee wave-driven mixing should berepresented in ocean and climate models, but currentlyit is not. Citation: Nikurashin, M., and R. Ferrari (2013),Overturning circulation driven by breaking internal waves in thedeep ocean, Geophys. Res. Lett., 40, doi:10.1002/grl.50542.