The Main Features of Mesoscale Water Structure in the Vicinity of the Pribilof Islands (Eastern Bering Sea)

摘要

Hydrophysical and hydrochemical survey carried out in 1992-94 revealed mesoscale peculiarities of waters' structure in the vicinity of the Pribilof Islands on the background of the large-scale oceanographic structure of the eastern Bering Sea. The existence of specific features in the structure of shelf waters in the Pribilof region and the difference of the area from the rest of basin are due to non-uniformity of the bottom topography-the island elevations. The mesoscale near-island water structure in general proved to be topological similar to the macroscale system of oceanographic domains and fronts on the eastern Bering shelf, known from previous studies. Like this, Coastal Fronts found around each of the Pribilof Islands are by their nature similar to the In- ner front located along the North-American coast. The Outer domain of the eastern Bering Sea shelf is separated from the Oceanic waters by the Shelf Break Front. The conducted study proved the Shelf Break Front being also an element of the local frontal system of the Pribilof region. Shelf waters between the Shelf Break Front and the Coastal Fronts around the Islands are bordered by the subsurface Shelf Partition Front and take apart into the Interior shelf waters and the Exterior shelf waters in respect to their island. Analysis of the original data and its comparison with the earlier results enable a reasoned assumption that the Shelf Partition Front is a mesoscale analogue of the macroscale Middle Front. The Interior and the Exterior shelf waters as well as Shelf Partition Front outlined as composit components of the local water structure of the Pribilof region can be referred to as mesoscale disclosures of the Middle domain and the outer domain, respectively.