FN Archimer Export Format
PT J
TI Removing biases in oceanic turbulent kinetic energy dissipation rate estimated from microstructure shear data
BT 
AF Ferron, Bruno
   BOURUET AUBERTOT, P. Bouruet
   Cuypers, Y.
   Vic, Clement
AS 1:1;2:2;3:2;4:3;
FF 1:;2:;3:;4:PDG-ODE-LOPS-OH;
C1 Univ. Brest, CNRS, IFREMER, IRD, Laboratoire d'Océanographie Physique et Spatiale, IUEM, Brest, France
   LOCEAN-IPSL, Sorbonne Univ. (UPMC, Univ Paris 06)-CNRS-IRD-MNHN, Paris, France
   Univ. Brest, CNRS, IFREMER, IRD, Laboratoire d'Océanographie Physique et Spatiale, IUEM, Brest, France
C2 CNRS, FRANCE
   UNIV SORBONNE, FRANCE
   IFREMER, FRANCE
SI BREST
SE PDG-ODE-LOPS-OH
UM LOPS
IN WOS Ifremer UMR
   WOS Cotutelle UMR
   copubli-france
   copubli-univ-france
IF 2.2
TC 3
UR https://archimer.ifremer.fr/doc/00800/91223/96972.pdf
   https://archimer.ifremer.fr/doc/00800/91223/99306.zip
LA English
DT Article
CR MOMARSAT : MONITORING THE MID ATLANTIC RIDGE
   MOMARSAT2021
   VAD
BO L'Atalante
   L'Europe
DE ;Turbulence;Mixing;In situ oceanic observations;Data processing/distribution
AB To calculate a turbulent kinetic energy dissipation 11 rate from the microstructure vertical shear of the horizontal velocity via a spectral analysis, shear spectra need first to be cleaned from vibrations of the moving vehicle. Unambiguously, this study shows that the spectral cleaning must be applied all over the frequency range and not only at frequencies larger than 10 Hz, as a recent study suggested. For a Vertical Microstructure Profiler VMP-6000, not correcting for vehicle vibrations below 10 Hz leads to overestimated dissipation rates from 50 to 700% for usual downcast velocities and for weak dissipation rates (ε < 1 × 10−9 W kg−1). Vibrations concern all vehicles but the exact vibrational frequency signature depends on the vehicle shape and its downcast velocity. In any case, a spectral cleaning over the whole frequency range is strongly advised. This study also reports on a systematic low bias of inferred dissipation rates induced by the spectral cleaning when too few degrees of freedom are available for the cleaning, which is usually the default of the standard processing. Whatever the dissipation rate level, not correcting for the bias leads to underestimated dissipation rates by a factor 1.4 to 2.7 (with usual parameters), the exact amplitude of the bias depending on the number of degrees of freedom and on the number of independent accelerometer-axis used for the cleaning. It is strongly advised that such a bias is taken into account to recompute dissipation rates of past data sets and for future observations. 
PY 2023
PD JAN
SO Journal Of Atmospheric And Oceanic Technology
SN 0739-0572
PU American Meteorological Society
VL 40
IS 1
UT 000932767800007
BP 129
EP 139
DI 10.1175/JTECH-D-22-0035.1
ID 91223
ER

EF