Hydrography within the Central and East Basins of the Bransfield Strait, Antarctica

Abstract

Abstract The hydrography in the central and east basins of the Bransfield Strait is examined using data collected along a track 340 km long through the strait in November 1995, in conjunction with historical data from the NODC database. Circumpolar Deep Water (CDW) was seen throughout most of the central basin and the western east basin, in contrast to earlier studies that have shown CDW being absent or only weakly present in the strait. In the western part of the central basin the CDW was present as a narrow band near Deception Island with strong thermal gradients at its southern boundary, consistent with previous observations. Local deep-water formation produces bottom waters in the central and east basins that are distinct from one another and distinct from the surrounding deep waters outside the strait. The east basin has a more complex stratification than the central basin that must be the result of multiple sources. A model presented here explains the deep water in the east basin as a mixture betwee...