Flow of Antarctic Bottom Water at the output of the Vema Channel

Abstract

The pathways of the coldest part of the Antarctic Bottom Water (AABW) with potential temperature θ < 0.0°C in the Vema Channel and the pathways of this water flowing out of the channel to the Brazil Basin are studied on the basis of the data collected during the Russian expeditions in 2003, 2009–2012, and historical CTD data. It is shown that the AABW flows to the north in the Vema Channel as two streams, one of which is located in the deep channel and the other approximately 300 m higher over the western slope of the channel. It was found that the northern end of the deep channel is not located near 26°40′ S, 34°00′ W as a widening in the northern direction to the Brazil Basin as follows from the dataset of digital topography (Smith and Sandwell, 1997) but continues in the eastern direction. A weaker northerly flow of the cold AABW was also found from the results of the measurements in 2012, which is confined to a branch of the Vema Channel continuation.