Baroclinic transport across Drake Passage from the cDrake array

CHIDICHIMO, M. P.; DONOHUE, K. A.; WATTS, D. R.; TRACEY, K. L.

Salt Lake City

Congreso; Ocean Sciences Meeting; 2012

American Geophysical Union

The cDrake array was deployed in 2007 to continuously monitor the Antarctic Circumpolar Current transport in Drake Passage for four years. The array consists of a transport line spanning 800 km across Drake Passage (22 Current and Pressure-recording Inverted Echo Sounders (CPIES) and 3 current meter moorings) and a local dynamics array (21 CPIES). Here we present the first three-year long continuous time series of baroclinic transport across Drake Passage. Our best estimate of the mean baroclinic transport referenced to and above 3500 m across the passage is 99.0 ± 10.6 Sv. The baroclinic transport is steady during the first three years of measurements. Approximately three quarters of the total baroclinic transport is carried by the Subantarctic Front and the Polar Front. The mean cross-passage near-bottom velocity determined from the deep (> 3000 m depth) current meter records is 2.0 cm/s. This mean velocity gives an estimate of the barotropic transport over a 717 km span of Drake Passage and through 3500 m depth of 50 Sv.