Introduction
Under Antarctic ice
It is difficult enough to get to Antarctica, but to get through the frozen sea ice and into the ocean beneath is even more challenging. But here we find rich communities of animals in one of the last undisturbed ecosystems on the planet. For ecologists, the opportunity to study and understand this fully functioning and balanced system is unparalleled. Only by understanding function and processes in a system in equilibrium can we understand a system in flux. Most of our world today is responding to recent rapid changes in conditions; change in itself is normal but the rate and intensity of the changes we are now experiencing are outside the normal range. Organisms and communities are showing signs of stress as they attempt to keep pace with the swift changes.
The sea ice from above. Photo credit Jeff Miller.
And below. Antarctic organisms are adapted to water temperatures that hover around the freezing point, -1.9 degrees C. Warming trends may make Antarctic species less competitive in their native habitats.
Getting in deep
Marine ecological research has focused on the most easily accessible areas of the ocean, the shallow seafloor and surface layers that are within range of Scuba divers. But this thin rind is less than 2 percent of the World Ocean. Greater depths remain relatively unexplored, especially in regions where ice cover makes them doubly inaccessible, especially to our existing robotic tools that are the size of small cars.
Divers Bob Zook and Nick Huerta give the “all okay” sign at shallow depths.
Underwater robots
Remotely operated vehicles or ROVs are controlled from the surface via a joystick and tether. The tether carries information up to the pilot (for example, images of the seafloor, navigational data) and commands from the pilot to the robot (such as turn right, or move forward). ROVs come in a range of sizes from the micro class VideoRay to heavy work class ROVs that can weigh 4 tons. The remote presence allows us to explore and research inaccessible habitats that are too dangerous for direct human presence – places like deep water under the ice in Antarctica.
The ROV SCINI goes where pilot Bob Zook, visible in the background above water, cannot. This image was taken by a VideoRay ROV, launched through the hole in the ice before SCINI.
Making holes
There are three proven methods for getting through Antarctic sea ice: drilling, blasting, and melting. Melting is time consuming and requires a full camp to refuel the melting rig every few hours. Blasting requires explosive experts. Drilling can be easy or hard, depending on the size of the hole you need. For a small hole (20 cm) you need only a hand held power head and a couple of people. The ROV we are building on this project, SCINI, is designed to take advantage of this easy access to the ocean by being able to slip down a small hole.
Drilling a hole through the sea ice big enough for SCINI requires only a few people and an hour of work.