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During winters, the northern Adriatic Sea experiences frequent, intense cold‐air outbreaks that drive oceanic heat loss and imprint complex but predictable patterns in the underlying waters. This strong, reliable forcing makes this region an excellent laboratory for observational and numerical investigations of air‐sea interaction, sediment and biological transport, and mesoscale wind‐driven flow. Narrow sea surface wind jets, commonly known as “bora,” occur when cold, dry air spills through gaps in the Dinaric Alps (the mountain range situated along the Adriatic's eastern shore). Horizontal variations in these winds drive a mosaic of oceanic cyclonic and anticyclonic cells that draw coastal waters far into the middle basin. The winds also drive intense cooling and overturning, producing a sharp front between dense, vertically homogenous waters (North Adriatic Dense Water, or NAdDW) in the north and the lighter (colder, fresher), stratified waters of the Po River plume. Once subducted at the front, the NAdDW flows southward in a narrow vein following the isobaths (contours of constant depth) of the Italian coast. In addition to governing the basin's general circulation, these processes also influence sediment transport and modulate biological and optical variability

[1] A combination of recent intensive observations and simulations with two numerical models is used to revisit the issue of the northern Adriatic response to strong bora episodes. New observed and simulated data reinforce the view that an episode of strong bora wind provokes a double-gyre (cyclonic, Trieste, and anticyclonic, Rovinj) response north of the Po Delta -Pula line. During an intense bora episode, both measured and modeled statistics picture a downwind, highly polarized, and almost depth-independent flow within the Trieste gyre NW arm. Its NE arm maintains a sharp polarization and strong depth dependence while exhibiting lower speeds, with models in good accord with observations. The current statistics for Rovinj gyre provide lower maximum and average speed values and less polarized but still rather depth-independent flow, while exhibiting clockwise rotation. The north arm of the Senj gyre (positioned south of the Po Delta-Pula line) enjoys more lateral freedom, and exhibits less rectilinear flow. Our review reinforces the notion that modeling studies based on ECMWF wind forcing fail to properly take into account the orographic control of the Dinaric Alps, and to produce correct bora-induced gyral pattern. The COAMPS 1 model successfully simulated the onset, duration, and decay of the wind peaks, but exhibited a tendency to overpredict the strength of the bora wind. Our simulations have identified the shallow NW coastal strip as an important source of colder water observed in a sequence of remotely sensed SST fields derived from AVHRR data.Citation: Kuzmić, M., I. Janeković, J. W. Book, P. J. Martin, and J. D. Doyle (2006), Modeling the northern Adriatic double-gyre response to intense bora wind: A revisit,

No abstract

Abstract. The primary goal of this study was to incorporate data-derived harmonic constants into a complex dynamic model using a form of variational data assimilation, with a view to improve the prediction of 7 dominant tidal constituents in the Adriatic Sea. Firstly, harmonic-constant data for 6 Adriatic stations were fed into a steady-state, 3-D, forward/inverse model to furnish optimal boundary conditions (OBCs). Calculated OBCs were then used to derive individual constituent responses, as well as to synthesise sevenconstituent boundary conditions for the time stepping, 3-D model. A separate set of 25 stations provided control harmonic constant data. In validating the model output particular attention has been given to the often-ignored tidal currents. To that end 14 current meter data records were processed into tidal current ellipse parameters and used to examine the comparable model output. Comparison to gauge data has shown that the present solution is better than our own previous one, and shows an improvement over recent solutions by other authors. The model accurately reproduces available data with individual station amplitude differences rarely exceeding 1 cm, and with the phase error commonly staying well below 10 • . For all tidal constituents individual station differences result in RMSE in the 0.33-0.71-cm range for amplitude, and the 5.6 • -19.2 • range for phase. Semidiurnal currents appear to be modelled better than the diurnal ones (generally over-predicted). High eccentricity of both data and model-derived ellipses often impaired calculating the proper sense of rotation; inclination of the ellipses proved to be the most robust parameter, successfully predicted for most constituents at all depths.