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6 pages, 4 figures, Intensive sampling of the deep Mediterranean outflow 70 km W of the Strait of Gibraltar reveals a strong, tidally modulated gravity current embedded with large-amplitude oscillations and energetic turbulence. The flow appears to be hydraulically controlled at a small topographic constriction, with turbulence and internal waves varying together and increasing dramatically downstream of the choke point. These data suggest that a significant fraction of energy dissipation, mixing, and entrainment stress in gravity currents may occur in localized regions controlled by time-varying flow interactions with fine-scale topography. These findings highlight the important role of processes that are not resolved by global climate models (GCMs), which do not contain tides or mixing due to fine-scale topographic interactions. © 2012. American Geophysical Union. All Rights Reserved, This work was supported by the U.S. National Science Foundation, grants OCE-0825287, OCE-0825297, and the Spanish Ministerio de Ciencia e Innovación, grants CTM2008-06438-C02-01 and CTM2008-03422-E/MAR

I Encuentro de la Oceanografía Física Española (EOF), 13-15 de octubre 2010, Barcelona, The Straits of Gibraltar play an important role in the context of the global thermohaline circulation: dense, salty Mediterranean Water (MW) exiting through the straits facilitates the subduction and formation of deep Arctic Basin Waters, which constitute a major component of the North Atlantic Deep Water and the global conveyor belt. This presentation describes the results of a fifteen‐day long cruise realized on July 2009 by the BIO 'García del Cid' in the context of the project “Memory of Climate ‐ Meridional Overturning Circulation” (MOC‐MOC) on a 35 by 25 Km region centered at 35.85°N, 6.4°W. The aim of the study is to provide an account of the long‐period mass and salinity fluxes west of the Straits of Gibraltar, and the relative importance of mixing, frictional processes, tides, geostrophic adjustment, centrifugal forces and topographic steering. In order to obtain the general spatial distribution of the temperature and salinity fields five principal transects (22 stations) were realized perpendicular to the assumed path of the Mediterranean Outflow. A more detailed survey, including yo‐yo CTD transects, two moorings and two 24‐hour vertical time series, focused on a square box roughly one third of the length of the exterior domain, located at 35.75°N, 6.35°W. In total 418 CTD casts were performed. Property fields indicate that the trajectory of the MW Outflow is driven by the equilibrium between topographic steering and Coriolis forces. Diapycnal mixing develops as a result of the interplay between tidal currents, hydraulic jumps and internal waves generated in regions with strong bathymetry drops

Deep-water Circulation: Processes & Products. International Congress 16-18 june 2010, Baiona, Pontevedra, Spain, [EN] Deep-water circulation is a critical part of the global conveyor belt that regulates Earth's climate. The bottom current component of this circulation is hugely significant in shaping the deep seafloor, through erosion, transport and deposition. As a result a great variety of depositional and erosive features are developed, including a range of different drifts, sediment waves, moats, furrows, and abraded surfaces. The Baiona Congress will be focused specifically on processes and deposits related to bottom-water circulation, [ES] La circulación de aguas profundas es una parte crítica del sistema global que regula el clima de la Tierra. Las corrientes del fondo, componentes de esta circulación, son enormemente significativas para dar forma al fondo marino, mediante la erosion, trasporte y sedimentación. Como resultado, se desarrollan una gran variedad de sedimentos y rasgos erosivos, incluyendo un rango de diferentes flujos, olas de sedimentos, fosos, surcos y superficies desgastadas. El Congreso de Baiona se centrará específicamente en los procesos y los sedimentos relacionados con la circulación de aguas del fondo marino

Quasi-synoptic, three-dimensional surveys of physical and optical variability characterize the mesoscale features that dominate the Northern and Central Adriatic, following their response to strong forcing events. During winter (February), sampling emphasized the response to episodic Bora wind events. Although springtime (May) measurement program was designed to sample during the Po River spring freshette, freshwater discharge rates were more than a standard deviation below the 12-year mean and winds remained weak throughout the survey period, leading to a study of weakly forced dynamics in a strongly stratified, shallow water regime. Wintertime sampling included surveys of a strong shallow-water front and a prominent extension of the Po River plume. The surveys captured the evolution of a nearly vertical, compensated front that tilts as the strong Bora winds weaken. A broad survey of the northern basin characterized the structure of a Bora-driven Po plume extension and reveals cyclonic (anticyclonic) circulation to the north (south) of the plume, consistent with the response found in previous numerical experiments.

Quasi-synoptic, three-dimensional surveys of physical and optical variability characterize the mesoscale features that dominate the Northern and Central Adriatic, following their response to strong forcing events. During winter (February), sampling emphasized the response to episodic bora wind events. Although springtime (May) measurement program was designed to sample during the Po River spring freshette, freshwater discharge rates were more than a standard deviation below the 12-year mean and winds remained weakthroughout the survey period, leading to a study of weakly forced dynamics in a strongly stratified, shallow water regime. Wintertime sampling included survays of a strong shallow-water front and a prominent extension of the Po River plume. The surveys captured the evolution of a nearly vertical, compensated front that tilts as the strong bora winds weaken. A broad survey of the northern basin characterized the structure of a bora-driven po plume extension and reveals cyclonic (anticyclonic) circulation to the north (south) of the plume, consistent with the response found in previous numerical experiments.

Quasi-synoptic, three-dimensional surveys of physical and optical variability characterize the mesoscale features that dominate the Northern and Central Adriatic, following their response to strong forcing events. During winter (February), sampling emphasized the response to episodic bora wind events. Although spring time (May) measurement program was designed to sample during the Po River spring freshette, freshwater discharge rates were more than a standard deviation below the 12-year mean and winds remained weak throughout the survey period, leading to a study of weakly forced dynamics in a strongly stratified, shallow water regime. Wintertime sampling included surveys of a strong shallow-water front and a prominent extension of the Po River plume. The surveys captured the evolution of the strong bora winds weaken. A broad survey of the northern basin characterized the structure of a bora-driven Po plume extension and reveals cyclonic (anticyclonic) circulation to the north (south) of the plume, consistent with the response found in previous numerical experiments.