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Historical satellite, aircraft, and in situ data have shown that two anticyclonic gyres (the western and eastern Alboran gyres) are major ocean features of the Alboran Sea. An examination of several years of satellite imagery indicates that large variations in the surface expression of these two gyres occur and that on occasion one or the other gyre disappears (the disappearance of both gyres at the same time was not seen). The initial disappearance of either gyre occurs on a time scale of a week to 2 weeks, whereas the return may take from 3 weeks to 2 months. Various forcing mechanisms, i.e., winds, mass flux inflow through the Straits of Gibraltar and Sicily, and/or density, have been used in numerical ocean circulation models to study the dynamics of the western Mediterranean Sea. Various model results show relationships similar to those shown by the satellite imagery. However, no single forcing mechanism has been positively identified as the source of the disappearances, and the events may be a result of a combination of forcing mechanisms.

Quasi-synoptic hydrographic data and satellite imagery are used to describe the circulation and the structural variability of the Black Sea with particular emphasis on the Turkish coast. The circulation is indicated to involve a variable cyclonic circulation with no apparent central locus and a well-defined cyclonic "Rim Current" containing meanders and interacting eddy fields confined to the shelf slope. Interspersed between the coastal eddies are filaments and intense jets, often with dipole eddies at their termina. The extension of these features across the shelf-slope into the central basin offshore waters implies important dynamical processes related to the shelf-deep basin exchanges. These features are often steered by the topography and evolve continuously through the mixed baroclinic-barotropic instability of the Rim Current.

Until recently, the surface circulation of the Balearic Sea has been viewed as largely cyclonic with a fairly quiescent central dome. However, recent studies involving ship data, tracked drifters, current meter moorings, and satellite imagery indicate that this sea has strong mesoscale variability and a more complex general circulation. These studies, together with an examination of registered satellite imagery collected during the Western Mediterranean Circulation Experiment (WMCE), indicate that the surface circulation is strong year‐round, and characterized by two permanent density fronts located on the continental shelf slope (the Catalan Front) and the Balearic Islands shelf slope (the Balearic Front). The Catalan Front is the more active of the two fronts. In the northern area, a plume of cold water is frequently observed moving southward along the continental slope region, shedding dipole eddies along the leading edge of the plume. In addition, the Catalan Front continuously spawns energetic filaments that appear to be associated with the plume of cool water. The likely mechanism of formation of these filaments is the deflection of the cold water by the regional submarine canyons.

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