FN Archimer Export Format
PT J
TI Deep cycle turbulence in Atlantic and Pacific cold tongues
BT 
AF Moum, James N.
   Hughes, Kenneth G.
   Shroyer, Emily L.
   Smyth, William D.
   Cherian, Deepak
   Warner, Sally J.
   Bourlès, Bernard
   Brandt, Peter
   Dengler, Marcus
AS 1:1;2:1;3:2;4:1;5:3;6:4;7:5;8:6,7;9:6;
FF 1:;2:;3:;4:;5:;6:;7:;8:;9:;
C1 College of Earth Ocean, and Atmospheric Sciences Oregon State University Corvallis Oregon ,USA
   Office of Naval Research Arlington VA, USA
   National Center for Atmospheric Research Boulder CO ,USA
   Departments of Physics and Environmental Studies Brandeis University Waltham MA ,USA
   Institut de Recherche pour le Développement Brest, France
   GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel ,Germany
   Kiel Unviversity Kiel, Germany
C2 UNIV OREGON, USA
   OFF NAVAL RES, USA
   NCAR, USA
   UNIV BRANDEIS, USA
   IRD, FRANCE
   IFM GEOMAR, GERMANY
   UNIV KIEL, GERMANY
SI BREST
SE IRD
IF 5.2
TC 9
UR https://archimer.ifremer.fr/doc/00765/87666/93163.pdf
LA English
DT Article
CR PIRATA
DE ;equator;diurnal;turbulence;mixing;scaling;timeseries
AB Multiyear turbulence measurements from oceanographic moorings in equatorial Atlantic and Pacific cold tongues reveal similarities in deep cycle turbulence (DCT) beneath the mixed layer (ML) and above the Equatorial Undercurrent (EUC) core. Diurnal composites of turbulence kinetic energy dissipation rate, ϵ, clearly show the diurnal cycles of turbulence beneath the ML in both cold tongues. Despite differences in surface forcing, EUC strength and core depth DCT occurs, and is consistent in amplitude and timing, at all three sites. Time-mean values of ϵ at 30 m depth are nearly identical at all three sites. Variations of averaged values of ϵ in the deep cycle layer below 30 m range to a factor of 10 between sites. A proposed scaling in depth that isolates the deep cycle layers and of ϵ by the product of wind stress and current shear collapses vertical profiles at all sites to within a factor of 2. Plain Language Summary The equatorial cold tongues are large areas of the ocean that extract a globally disproportionate amount of heat from the atmosphere, and where that heat is mixed downward to the deeper ocean, a critical process in climate regulation. This mixing is dominated by deep cycle (DC) turbulence, a well-documented feature of the central equatorial Pacific cold tongue. Poleward of the Equatorial Undercurrent, nighttime cooling of the sea surface causes increases in turbulence to the depth of the ML, typically a few tens of meters, below which turbulence is much reduced. On the equator, in contrast, opposing currents at the surface and roughly 100 m below the surface create a dynamic environment in which nightly increases in turbulence occur over many tens of meters below the ML base. This has been termed DC turbulence. Here, using massive data sets from both Pacific and Atlantic cold tongues, we show that DC turbulence is present at each location and its main characteristics are consistent between them. 
PY 2022
PD APR
SO Geophysical Research Letters
SN 0094-8276
PU American Geophysical Union (AGU)
VL 49
IS 8
UT 000787186700001
DI 10.1029/2021GL097345
ID 87666
ER

EF