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Phytoplankton in the ocean produce half of the oxygen in the Earth’s atmosphere. Iron supply limits the growth of phytoplankton in Antarctic waters. Hydrothermal systems cooling active submarine volcanoes may be adding iron to the Southern Ocean. Oceanographer, Maine native, and University of Tasmania (Australia) Professor Mike Coffin will present initial findings arising from a two-month Antarctic research voyage he led earlier this year, including a 15-minute documentary film featuring an erupting volcano.