The dynamics of the Southern Adriatic is dominated by the presence of a quasi-permanent cyclonic gyre that in the winter season creates the conditions for the open-ocean convection and the production of dense and oxygenated waters. Studies show that two types of dense water formation processes occur during winter within the Adriatic Sea: the major portion of the Adriatic Deep Water (ADW) is formed through open ocean convection inside the Southern Adriatic Pit (SAP) within the cyclonic gyre, while the remaining dense water is formed on the continental shelf of the Northern and Middle Adriatic that moves southward and ultimately sinks to the bottom of the SAP ([Ovchinnikov et al. (1985)][Bignami et al. (1990)] [Malanotte-Rizzoli (1991)]). The eastern margin is characterized by the influence of the incoming water of Ionian origin which flow northward being restricted mainly to the continental slope. This area is interested by the Levantine Intermediate water (LIW) that occupies the layer between 150 and 600m.
The coastal zone of Albanian and Montenegro in the eastern margin consists of a narrow shelf area North of the Strait of Otranto, with smooth bathymetry and with circulation features presumably determinate by inflowing Ionian waters, by local winds, and by relatively large amounts of the riverine inflow. The latest provide a strong contribution to the Adriatic freshwater budget, in a way that their influence in feeding the freshwater coastal zone is sometimes felt far downstream along the Croatian coast . The current state of knowledge of oceanographic characteristics of the Albanian shelf is very limited due to very small number of in-situ oceanographic studies that have been undertaken in the area. Numerical simulations and satellite infrared images indicates that the circulation on the Albanian shelf responds strongly to the local wind forcing [Bergamasco and Gacic (1996)]. More specifically, the northeasterly wind generates very intense coastal upwelling along the Albanian shoreline due to the sudden change of the coastline orientation in that area. Bora wind induces an undercurrent at intermediate depths near the Albanian shelf break, which is directed in the opposite direction of the Levantine Intermediate Water (LIW) inflow from the Ionian. Therefore, in addition to coastal upwelling, Bora in the Strait of Otranto weakens and occasionally blocks completely the LIW inflow.
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