FN Archimer Export Format
PT J
TI Enhanced Abyssal Mixing in the Equatorial Pacific Associated with Non-Traditional Effects
BT 
AF Delorme, Bertrand L.
   Thomas, Leif N
   Marchesiello, Patrick
   Gula, Jonathan
   Roullet, Guillaume
   Molemaker, M. Jeroen
AS 1:1;2:1;3:2;4:3,4;5:3;6:5;
FF 1:;2:;3:;4:;5:;6:;
C1 Earth System Science Department, Stanford University, Stanford, California
   IRD/LEGOS, Toulouse, France
   Univ. Brest, CNRS, IRD, Ifremer, Laboratoire d’Océanographie Physique et Spatiale (LOPS), IUEM, Brest, France
   Institut Universitaire de France (IUF), France
   Department of Atmospheric and Oceanic Sciences, University of California Los Angeles, Los Angeles, California
C2 UNIV STANFORD, USA
   IRD, FRANCE
   UBO, FRANCE
   INST UNIV FRANCE, FRANCE
   UNIV CALIF, USA
UM LOPS
IN WOS Cotutelle UMR
   copubli-france
   copubli-int-hors-europe
IF 3.806
TC 4
UR https://archimer.ifremer.fr/doc/00696/80797/84292.pdf
LA English
DT Article
DE ;Tropics;Abyssal circulation;Diapycnal mixing;Waves;oceanic
AB Recent theoretical work has shown that, when the so-called nontraditional effects are taken into account, the reflection of equatorially trapped waves (ETWs) off the seafloor generates strong vertical shear that results in bottom-intensified mixing at the inertial latitude of the ETW via a mechanism of critical reflection. It has been estimated that this process could play an important role in driving diapycnal upwelling in the abyssal meridional overturning circulation (AMOC). However, these results were derived under an idealized configuration with a monochromatic ETW propagating through a flat ocean at rest. To test the theory in a flow that is more representative of the ocean, we contrast a set of realistic numerical simulations of the eastern equatorial Pacific run using either the hydrostatic or quasi-hydrostatic approximation, the latter of which accounts for nontraditional effects. The simulations are nested into a Pacific-wide hydrostatic parent solution forced with climatological data and realistic bathymetry, resulting in an ETW field and a deep circulation consistent with observations. Using these simulations, we observe enhanced abyssal mixing in the quasi-hydrostatic run, even over smooth topography, that is absent in the hydrostatic run. The mixing is associated with inertial shear that has spatiotemporal properties consistent with the critical reflection mechanism. The enhanced mixing results in a weakening of the abyssal stratification and drives diapycnal upwelling in our simulation, in agreement with the predictions from the idealized simulations. The diapycnal upwelling is O(10) Sv (1 Sv ≡ 106 m3 s−1) and thus could play an important role in closing the AMOC. 
PY 2021
PD JUL
SO Journal Of Physical Oceanography
SN 0022-3670
PU American Meteorological Society
VL 51
IS 6
UT 000751705900010
BP 1892
EP 1914
DI 10.1175/JPO-D-20-0238.1
ID 80797
ER

EF