%0 Journal Article
%T Microstructure observations during the spring 2011 STRATIPHYT-II cruise in the northeast Atlantic
%A E. Jurado
%A H. A. Dijkstra
%A H. J. van der Woerd
%J Ocean Science (OS) & Discussions (OSD)
%D 2012
%I Copernicus Publications
%R 10.5194/os-8-945-2012
%X Small-scale temperature and conductivity variations have been measured in the upper 100 m of the northeast Atlantic during the STRATIPHYT-II cruise (Las Palmas¨CReykjavik, 6 April¨C3 May 2011). The measurements were done at midday and comprised 2 to 15 vertical profiles at each station. The derived turbulent quantities show a transition between weakly-stratified (mixed layer depth, MLD, <100) and well-mixed waters (MLD > 100), which was centered at about 48¡ã N. The temperature eddy diffusivities, KT, range from 10 5 to 100 m2 s 1 in the weakly-stratified stations, and range from 3 ¡Á 10 4 to 2 ¡Á 100 m2 s 1 in the well-mixed stations. The turbulent kinetic energy dissipation rates, ¦Å, range from 3 ¡Á 10 8 to 2 ¡Á 10 6 m2 s 3 south of the transition zone, and from 10 7 to 10 5 m2 s 3 north of the transition zone. The station-averaged KT values throughout the mixed layer increase exponentially with the wind speed. The station-averaged ¦Å values throughout the mixed layer scale with the wind stress similarity variable with a scaling factor of about 1.8 in the wind-dominated stations (¦Å ¡Ö 1.8 u¡î3/( ¦Êz)). The values of KT and ¦Å are on average 10 times higher compared to the values measured at the same stations in July 2009. The results presented here constitute a unique data set giving large spatial coverage of upper ocean spring turbulence quantities.
%U http://www.ocean-sci.net/8/945/2012/os-8-945-2012.pdf