Ocean Science www.ocean-sci.net 1812-0784 1812-0792 6 1 2010 10.5194/os-6-331-2010 http://www.ocean-sci.net/6/331/2010/ http://www.ocean-sci.net/6/331/2010/os-6-331-2010.html http://www.ocean-sci.net/6/331/2010/os-6-331-2010.pdf 331 343 2010-03-03 Mediterranean intermediate circulation estimated from Argo data in 2003–2010 M. Menna mmenna@ogs.trieste.it P. M. Poulain Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Sgonico (TS), Italy Data from 38 Argo profiling floats are used to describe the intermediate Mediterranean currents for the period October 2003–January 2010. These floats were programmed to execute 5-day cycles, to drift at a neutral parking depth of 350 m and measure temperature and salinity profiles from either 700 or 2000 m up to the surface. At the end of each cycle the floats remained at the sea surface for about 6 h, enough time to be localised and transmit the data to the Argos satellite system. The Argos positions were used to determine the float surface and intermediate displacements. At the surface, the float motion was approximated by a linear displacement and inertial motion. Intermediate velocities estimates were used to investigate the Mediterranean circulation at 350 m, to compute the pseudo-Eulerian statistics and to study the influence of bathymetry on the intermediate currents. Maximum speeds, as large as 33 cm/s, were found northeast of the Balearic Islands (western basin) and in the Ierapetra eddy (eastern basin). Typical speeds in the main along-slope currents (Liguro-Provençal-Catalan, Algerian and Libyo-Egyptian Currents) were ~20 cm/s. In the central and western part of Mediterranean basin, the pseudo-Eulerian statistics show typical intermediate circulation pathways which can be related to the motion of Levantine Intermediate Water. 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