Southwest Atlantic Breakout GroupChair: Billy MooreRapporteur: Tina van de Flierdt

Participants: Steven GoldsteinGideon HendersonFelipe NiencheskiPeter StathamJana Friedrich

Three Proposed Sections

Cruise 1: Along the South American Shelf

Main goal: capture and understand productivity onone of the largest shelf regions outside the Arctic Ocean(strong seasonality – Oct/Nov = peak signal – do two cruises)

start in Rio, go to Comodoro Rivadavia (probably join up with Drake cruise?)

potential sources of Fe (micronutrients): dust, rivers, submarine groundwater discharge, upwelling

recommendation: set up a dust/air collection station on the Falkland Islands

Chl-a

Night light

Dust model

Chl-a

Cruise 2: Zonal Section

Main goal: capture all the main Atlantic water masses along a zonal section

start from Buenos Aires, go into the deep Argentine basinAnd then along 40S over to the mid Atlantic ridge captures a major river outflow, a margin with terrigenousinput, goes into a ridge with carbonate sedimentation

for proxy calibration cores should be taken on the transectAcross the shelf and close to the ridge (grab samples in themiddle of the basin are sufficient)

Create a baseline station on the shelf.

Cruise 3: Meridional Section

Main goal: capture all the main Atlantic water masses along the meridionalflow path

following the center of basins starting in the Brazil Basin,Across the Rio Grande rise going into the Argentine Basin

entrance of Southern Ocean water masses (AAIW, AABW)into the western Atlantic Basin (connects to Drake cruise)

far field effects of dust input, comparison of seawater signalto observations at the margins

Create a baseline station inthe Argentine basin.

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Two possible cruise tracks (approximate!)