Browse by author
Lookup NU author(s):
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
In the Southern Ocean, small-scale turbulence causes diapycnal mixing which influences important water mass transformations, in turn impacting large-scale ocean transports such as the Meridional Overturning trculation (MOC), a key controller of Earth's climate. We present direct observations of mixing over the Antarctic continental slope between water masses that are part of the Southern Ocean MOC. A 12 h time series of microstructure turbulence measurements, hydrography, and velocity observations off Elephant Island, north of the Antarctic Peninsula, reveals two concurrent bursts of elevated dissipation of O(10−6) W kg−1, resulting in heat fluxes ∼10 times higher than basin-integrated Drake Passage estimates. This occurs across the boundary between adjacent adiabatic upwelling and downwelling overturning cells. Ray tracing to nearby topography shows mixing between 300 and 400 m is consistent with the breaking of locally generated internal tidal waves. Since similar conditions extend to much of the Antarctic continental slope where these water masses outcrop, diapycnal mixing may contribute significantly to upwelling.
Author(s): Mead Silvester J, Lenn YD, Polton JA, Rippeth TP, Morales Maqueda MA
Publication type: Article
Publication status: Published
Journal: Geophysical Research Letter
Print publication date: 12/12/2014
Online publication date: 22/10/2014
Acceptance date: 20/10/2014
ISSN (print): 0094-8276
ISSN (electronic): 1944-8007
Publisher: American Geophysical Union
Altmetrics provided by Altmetric