Under Arctic Ice
The Hidden Ocean
CREDIT: E. Siddon, UAF, Hidden Ocean 2005, NOAA
Breaking the Ice
In 2005, 35 researchers from the US, Canada, China, and Russia boarded the US Coast Guard Cutter Healy and headed for one of the deepest areas of the Arctic Ocean. Funded and organized by the National Oceanic and Atmospheric Administration’s (NOAA) Office of Ocean Exploration and in support of the Census of Marine Life, they used a wide range of technologies to add to a baseline of data about Arctic species, against which to measure change.
The world beneath the ice is magical, but seeing it first-hand requires braving the cold. Divers have to tolerate temperatures of 30 degrees Fahrenheit (about -2° Celsius). To stay warm they wear thermal undergarments and use special gear called dry suits. Sunlight filters through the ice layer bathing the underwater habitats in shades of blue. Because the water is so clear, visibility can extend for hundreds of feet.
The mission used an ROV (Remotely-Operated Vehicle) to dive deeper than ice divers. ROVs can also operate longer than manned submersibles. The ROV was equipped with lights and a high-definition video camera, allowing the scientists to bring a stunning array of images through a fiber-optic tether up to the ship.
An array of alien-like animals can be found from the shallows to the deep in the Arctic Sea. Ranging in size from just a few millimeters to several meters long, their bodies are often gelatinous (jelly-like), translucent, and some are bioluminescent. These delicate creatures are hard to study. Nets can damage them and some preservatives destroy their fragile bodies.
Zooplankton – Greek for animal and drifting – are tiny creatures that cannot swim enough to overcome currents. They range in size from single-cells to larger copepods, krill, shrimp, and jellyfish, and are a vital part of the marine food web. They feed on microscopic plants called phytoplankton. And in turn, zooplankton are the main food source for many of the bigger animals in the Arctic, such as fish and whales.
The 'Mud People'
Benthic scientists on the ship are called "mud people" because because they bring up samples from the seafloor using bottom-trawl nets and "box corers" that collect mud. The bottom trawl is dragged along the seafloor, and the box corer grabs a square chunk of the seafloor sediment. Then the researchers on the ship pull up the sample and comb through the mud for critters to study.