During the ADELIE project, forty surface drifters were deployed in the region of the Antarctic Slope Front and the Weddell Front in conjunction with a hydrographic section crossing the continental shelf and slope describing the outflow from the Weddell Sea. The drifters were strongly steered by contours of f/h. Shear in the mean flow made the dominant contribution to dispersion in the along-f/h direction, but eddy processes were more important in dispersing particles across contours of f/h. The flow was dominated by three barotropic northward-flowing currents associated with frontal features: the Antarctic Coastal Current, Antarctic Slope Front and Weddell Front. The strongest baroclinic flows were confined between the Slope Front and the Weddell Front over the steepest part of the continental slope. The total transport snapshot across the ADELIE section was 46 ±8 Sv, larger than previous estimates.

The drifters revealed the pathways taken by water masses on the continental shelf and slope, and likely also by passive particles such as krill larvae. Some drifters were carried westward around the Peninsula; some followed the 1000-m isobath to the east alongthe southern edge of the South Scotia Ridge, and some became entrained in a large standing eddy over the South Scotia Ridge. Particles tracked in an eddy permitting ocean model ORCA show that the interannual variations in the numbers of 'krill' reaching South Georgia from the Antarctic Peninsula are likely forced by changes in the wind forcing associated with the Southern Annular Mode.

Finally, I will discuss our forthcoming GENTOO project during which we will deploy Seagliders to document the variability of physical, chemical and biological parameters during an Antarctic summer in the northwest Weddell Sea. A specially-designed small single-frequency echo sounder has been installed into a Seaglider to measure acoustic backscatter for assessing krill populations and dynamics. I will present some preliminary results of the echo sounder from trial deployments. The talk will end with the plans for the GENTOO fieldwork in early 2012 in the Weddell Sea.

Dr. Heywood is a Professor of Physical Oceanography in the Meteorology, Oceanography and Climate Dynamics Group in the School of Environmental Sciences at the University of East Anglia in Norwich, UK. Her main research interests are in large scale observational oceanography. Regions currently being studied include the Southern Ocean, North Atlantic and the east coast of Greenland. Additionally, her research addresses the circulation, processes and dynamics of the polar oceans, the most critical part of the global climate system.

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