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Realistic simulations of the Adriatic Sea for over 125 days are conducted using the Navy Coastal Ocean Model with atmospheric forcing provided by the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS is a registered trademark of the Naval Research Laboratory (COAMPS™)). In two separate simulations of the Adriatic, a nested 2‐km‐resolution ocean model is forced by the inner (4‐km) and outer (36‐km) nests of the atmospheric model. Two meteorological stations and two acoustic Doppler current profiler observation sites are used to evaluate modeled atmosphere and ocean velocity fields for 28 January–4 June 2001. Modeled/observed correlations of atmospheric 10‐m velocity are greater than 0.85 for both resolution models. Oceanic 5‐ and 25‐m current fluctuations from both simulations generally match the magnitude and orientation of the observations. The 4‐km‐resolution atmospheric model is differentiated from the 36‐km‐resolution model by its ability to resolve the small‐scale flow structures of the “bora” wind and by its better agreement with observed wind velocity statistics. The ocean simulation forced by the 4‐km‐resolution model is distinguished from the one forced by the 36‐km‐resolution model by its ability to reproduce the expected double‐gyre circulation in the northern Adriatic and by its ability to better capture the magnitude and shape of the observed depth‐dependent velocity correlation with wind at the deeper site. Though the 36‐km forced ocean model agrees better with many observed velocity statistics, the 4‐km forced ocean model produces the highest correlations with observations (exceeding 0.78) at subsurface depths that are most strongly correlated with winds.

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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

High resolution, continuous current measurements made in the Korea/Tsushima Strait between May 1999 and March 2000 are used to examine current variations having time periods longer than 2 days. Twelve bottom-mounted acoustic Doppler current profilers provide velocity profiles along two sections: one section at the strait entrance southwest of Tsushima Island and the second section at the strait exit northeast of Tsushima Island. Additional measurements are provided by single moorings located between Korea and Tsushima Island and just north of Cheju Island in Cheju Strait. The two sections contain markedly different mean flow regimes. A high velocity current core exists at the southwestern section along the western slope of the strait for the entire recording period. The flow directly downstream of Tsushima Island contains large variability, and the flow is disrupted to such an extent by the island that a countercurrent commonly exists in the lee of the island. The northeastern section is marked by strong spatial variability and a large seasonal signal but in the mean consists of two localized intense flows concentrated near the Korea and Japan coasts. Peak nontidal currents exceed 70 cm s −1 while total currents exceed 120 cm s −1. The estimated mean transport calculated from the southwest line is 2.7 Sv (Sv 10 6 m 3 s −1). EOF analyses indicate total transport variations in summer are due mainly to transport variations near the Korea coast. In winter, contributions to total transport variations are more uniformly distributed across the strait.