The Weddell-Scotia Confluence

Abstract The Weddell-Scotia Confluence is the zone separating the waters of the Weddell Sea from those of the Scotia Sea. Available historical hydrographic station data were examined to improve the description of this boundary zone from its western limit near the northern tip of the Antarctic Peninsula (∼55°W) to 20°W. Vertical sections of potential temperature, salinity, oxygen and density, as well as horizontal property distributions, confirm that the waters in the western part of the Weddell-Scotia Confluence are more homogeneous in the vertical than the surrounding waters and that, at depth, this zone is characterized by relatively low temperatures and salinities and high oxygen values. Near the sea surface, on the other hand, the confluence is characterized by relatively high salinities and low oxygen values. The distinguishing characteristics attenuate toward the east. Previous speculation has been that the relative homogeneity of this zone is due to vertical convection driven during winter by ice f...