Scientists and ASC Marine Technicians head out on the zodiac to collect ice samples
near the West Antarctic Peninsula. Pictured from left to right: Kevin Arrigo (Stanford),
John Betz (ASC Marine Lab), Tom Sigmond (ASC Marine Lab), Yussi Delgado
(Monash Univeristy), John Butterfield (Stanford). Credit: Hannah Joy-Warren
(August 11, 2015) Nutrient-rich water from melting Antarctic glaciers nourishes the ocean food chain, creating feeding “hot spots” in large gaps in the sea ice, according to a new study.
New research finds that iron stored in the region’s glaciers is being shuttled by melting water to open areas of the ocean, called polynyas, where it stimulates growth of phytoplankton, ocean algae that form the base of the marine food chain. Krill and fish thrive on phytoplankton, and these smaller animals support penguins, seals and whales that feed and breed in the polynyas that ring the Antarctic coast, according to new research.
Watch Kevin Arrigo describe his research on Antarctica’s hot-spots,
the icy world of polynyas. Credit: Stanford University
Increased melting of Antarctic glaciers in the coming decades, which scientists say could occur as a result of climate change, could cause a spike in the amount of iron in the polynyas, according to the new study. The increased iron could boost phytoplankton in these open areas, potentially providing more food for the entire food chain, suggests the new study accepted for publication in Journal of Geophysical Research: Oceans, an American Geophysical Union journal.
“These coastal polynyas are sensitive to inputs from adjacent glaciers, and these glaciers are probably going to accelerate their melting in the future, which is certainly going to have implications for these polynyas,” said Kevin Arrigo, a biological oceanographer with the Department of Earth System Science at Stanford University in California, and lead author of the new study.