Distinctive features of water exchange across the Słupsk Sill (a full-scale experiment)

• Autorzy: Paka V. , Golenko N. , Korzh A.
• Języki publikacji: EN

Abstrakty

EN

The flows of brackish waters in the upper layer and saline waters in the lower layer meet above the Słupsk Sill, which makes this one of the most significant features of the Baltic Sea, controlling as it does the ventilation of the deep basins in its central region. Earlier high-resolution measurements using towed scanning probes conducted here for more than ten years had revealed the complexity and variability of the water dynamics in this area. Mapping surveys repeated in quick succession are needed to study the water exchange in such an area. A survey of this kind was attempted in October 2003 during the 57th cruise of the r/v ‘Professor Shtokman’. Three surveys were carried out in the areas of the Słupsk Sill, the eastern Bornholm Basin, and the western Słupsk Furrow by means of a scanning probe towed along closely-spaced transects. The water structure around the sill was different each time, despite the rather short time gaps between the surveys. As follows from the data analysis, during the first survey, the saline Bornholm waters flowed over the sill as an axially symmetrical jet and entrained the adjacent freshened cold waters of the intermediate layer. In ten days, this joint flow displaced to the southern flank of the sill and propagated in the Słupsk Furrow along its southern border, with the dense core of saline waters gradually moving over the bottom to the northern border. Concurrently, the contrary flow of the main volume of cold freshened waters, originating from northern areas and leaving the Baltic Sea, was pushed away from the southern wall of the furrow and blocked at a significant distance from the sill. In three days, the blocked waters forced their way through towards its northern flank. Just below these waters, waters of elevated salinity were found above the eastern slope of the sill at the depth of its ridge, while waters of a similar salinity occurred below the depth of the ridge above the western slope of the sill. There were no indications of intensive overflow in the central and southern areas of the sill. Accordingly, the return flow of Bornholm waters across the sill became possible.

Słowa kluczowe

EN

Sopot; water exchange; thermohaline structure; Slupsk Sill; saline water; conference; Baltic Sea; high-resolution transect; inflow water; brackish water

• Wydawca: -
• Czasopismo: Oceanologia
• Rocznik: 2006
• Tom: 48
• Numer: S
• Opis fizyczny: p.37-54,fig.,ref.

Twórcy

autor

Paka V.

• Atlantic Branch of the Shirshov Institute of Oceanology, Prospect Mira 1, 236000 Kaliningrad, Russia

autor

Golenko N.

autor

Korzh A.

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