Massive phytoplankton blooms under Arctic sea ice

Michael Stephens ’13 an Environmental Studies majors is a co-author on a paper in Science.  Phytoplankton blooms over Arctic Ocean continental shelves are thought to be restricted to waters free of sea ice. Here we document a massive phytoplankton bloom beneath fully consolidated pack ice far from the ice edge in the Chukchi Sea where light transmission has increased in recent decades due to thinning ice cover and proliferation of melt ponds. The bloom was characterized by extraordinarily high diatom biomass and rates of growth and primary production. Biogeochemical evidence suggests that under-ice phytoplankton blooms are widespread over nutrient-rich Arctic continental shelves and that satellite-based estimates of annual primary production in these waters is underestimated ~10-fold.