Surface of a refrozen melt pond with Melosira arctica filaments trapped in at one of the team's research stations.PHOTO COURTESY OF MAR FERNANDEZ-MENDEZ (ALFRED WEGENER INSTITUTE)Forests of filamentous algae that grow just beneath Arctic Sea ice are falling to the ocean floor earlier in the year than ever before. There, they provide unexpected fuel to a typically nutrient-poor environment, potentially altering the dynamics of the deep-sea ecosystem, according to new research published today (February 14) in Science from European scientists. Climate change, which has already contributed to thinner summer sea ice coverage, increased sunlight penetration, and accelerated melting in the Arctic, is likely a key factor in the ecological shift.
Aboard the research vessel Polarstern, researchers from Germany, the Netherlands, and Russia sampled ice-covered Eastern Central basins of the Arctic Ocean last summer, as Arctic sea ice coverage was receding to its lowest level in recorded history.
Using a submersible vehicle equipped with cameras, they saw heaps of fresh algae littering the normally barren seafloor 3–4 kilometers down. The algae, which consist of individual cells of a diatom, Melosira arctica, normally cling to the underside of the ice in long, filamentous threads, but break free and sink to the bottom as ice thins and cracks when temperatures warm.
Antje Boetius, biological oceanographer at the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, who led the research team, said that other polar explorers ...
