Understanding the Massive Phytoplankton Blooms Over the Australian-Antarctic Ridge

The Australian-Antarctic Ridge phytoplankton bloom is one of the most concentrated and largest blooms in the Southern Ocean and one of only three large blooms that consistently develop within offshore waters of the Antarctic Circumpolar Current, yet we know almost nothing about the processes driving it. Perhaps significantly, this bloom is located directly above two hydrothermal vents that are known to release large amounts of trace metals such as iron. The primary objective of this proposal is to combine remote sensing, modeling, and fieldwork to identify the physical and chemical processes responsible for delivering dissolved iron to the site of the recurring Australian-Antarctic Ridge bloom and characterize the biological and biogeochemical responses by the bloom to that iron input.

More Information About This Project

Participants Involved in This Project

Kevin in front of a red plane

Kevin Arrigo | Researcher Fellow

Department of Earth System Science | Stanford, California
Bhavna tossing a green apple in front of a chalkboard

Bhavna Rawal | Educator Fellow

Lonestar Community College-CyFair | Houston, TX

From the Blog

A Day in the Life
Preparing for an expedition to the Southern Ocean is an adventure in itself. You gather your base layers, boots, goggles, socks, and pack your camera and lenses, envisioning the polar environment—one of the most extreme on Earth. Imagine the biting wind on your cheeks and the sight of albatrosses, prions, penguins, humpback whales, and orcas, thriving in such harsh conditions. The excitement is palpable as you prepare to study the microscopic world that sustains this vast ecosystem. Beneath the icy waters lies an invisible world of phytoplankton, microscopic organisms that are the unsung heroes of the marine ecosystem. Despite their size, phytoplankton play a colossal role in maintaining life on Earth.
The bluest blue backdrop against a relentless twenty-four hour sun
The Power of Collaboration
I thought I had seen all of the colors of blue before my trip to the Far North. After all, I teach about the electromagnetic spectrum and the active and passive sensors that scientists use to understand our changing planet. And yet. There were blues in Kalaallit Nunaat that I had never seen before. While photographs don’t really capture the vibrancy of the colors, or the feeling of being there, they are a starting point for conveying what I mean.
Photo collage showing different kinds of fish
A Day in the Life
Polar STEAM brought me to Utqiaġvik in collaboration with Dr. Julia York from the University of Illinois. Dr. York’s post-doctoral work is investigating how Arctic fishes, specifically Iqalugaq (Boreogadus saida, Arctic Cod) and Uugaq (Eleginus gracilis, Saffron Cod), physiologically sense and adapt to the freeze thaw cycles that dominate the Arctic throughout the year. Unlike
Jeanette poses in front of a whale skull
A Day in the Life
My whirlwind polar adventure is coming to an end. After a very short 10 days (ALL DAY as the sun has not set in Alaska since mid-May), I find myself spending my last few hours in town reflecting on my experience both with the people as well as the research I helped with, all while admiring the tundra. Polar STEAM brought me to Utqiaġvik in collaboration with Dr. Julia York from the University of Illinois. Dr. York’s post-doctoral work is investigating how Arctic fishes, specifically Iqalugaq (Boreogadus saida, Arctic Cod) and Uugaq (Eleginus gracilis, Saffron Cod), physiologically sense and adapt to the freeze thaw cycles that dominate the Arctic throughout the year. Unlike some of the Antarctic fishes that Dr. York focused on during her PhD, Arctic cod experience a wider range of temperatures throughout the year, from freezing ocean water (28.4°F; -2°C) in the winter to up to mid-40s°F during the summer. Fishes are the same temperature as their environment and environmental temperature fluctuation means that during times of the year fishes must either swim away from the freezing water or adapt mechanisms to keep from freezing.
The team using the conductivity, temperature and depth tool on board the ship
A Day in the Life
The US academic research vessel RV Neil Armstrong departed from Nuuk, Greenland in early October. On the first leg of our journey, the science team’s initial purpose was to collect water samples and previously deployed instruments along a line of moorings at the southern entrance to Baffin Bay, a gateway between the Arctic and the north Atlantic. This line stretches from Sisimiut, on the west side of Greenland, to just off Cape Dyer, near the Canadian coast.