Transport of Antarctic bottom water through the kane gap, tropical NE Atlantic Ocean

Abstract

We study low-frequency properties of the Antarctic Bottom Water (AABW) flow through the Kane Gap (9 N) in the Atlantic Ocean. The measurements in the Kane Gap include five visits with CTD (Conductivityerature-Depth) sections in 2009-2012 and a year-long record of currents on a mooring using three AquaDopp current meters. We found an alternating regime of flow, which changes direction several times during a year. The seasonal signal seems to dominate. The maximum daily average values of southerly velocities reach 0.20 m s-1, while the greatest north-northwesterly velocity is as high as 0.15 m s-1. The velocity and transport at the bottom are aligned along the slope of a local hill near the southwestern side of the gap. The distribution of velocity directions at the upper boundary of AABW is wider. The transport of AABW (Θ < 1.9 C) based on the mooring and LADCP (Lowered Acoustic Doppler Current Profiler) data varies approximately within ±0.35 Sv in the northern and southern directions. The annual mean AABW transport through the Kane Gap is almost zero. © Author(s) 2013. CC Attribution 3.0 License.