Dr Guy Williams — Antarctic Climate and Ecosystems Cooperative Research Centre
Sea ice thickness represents one of these sort of holy grail at the moment. It’s something that we have difficulty in measuring with great accuracy and with any sort of great success on large scales. So thickness is important because we want to know how much there is. We’ve got a good idea of the area from the satellites, but the satellites can’t tell us the thickness and without the thickness we won’t know the total volume or the total amount of sea ice.
Dr Clay Kunz – Woods Hole Oceanographic Institution
So this is an Autonomous Underwater Vehicle, or AUV, and what it does is it’s a free swimming underwater robot. So it carries on board all of its power and intelligence and navigation equipment so that it is basically free swimming through the water and doing its own thing, as opposed to be being remotely controlled over a tether.
On this particular trip, since we are looking at the underside of the ice, we want to be pretty close to it. So we are driving around, so far we’ve been generally 20 metres underneath the water actually which is less distance under the ice because of course the ice sticks down into the water quite away.
The AUV has a lot of waypoints that it’s trying to get to as it is driving around underwater and the last waypoint that its set to get to is basically back where it started again, which is in open water off the stern of the ship.
Dr Guy Williams — Antarctic Climate and Ecosystems Cooperative Research Centre
It represents a leap forward in observational capability in terms of how we can measure thickness. The multi-beam sonar that we have on this AUV will provide us with a 3-D view of the underside of the sea ice. That will, together with the surface measurements that we are getting from other platforms, like the helicopter, we’ll have a full 3-D map of the entire sea ice flow.
Dr Jan Lieser — Antarctic Climate and Ecosystems Cooperative Research Centre
We are here in Antarctica to measure the thickness of the snow cover and the sea ice which is separating the atmosphere from the ocean. When we know how the thickness of the sea ice cover is changing over time we can estimate the influence of global changing climate on the overall environment down here, which includes not only the physical environment, in terms of sea ice, atmosphere and ocean, but also the biosphere.
We have this helicopter equipped with a whole heap of instruments which we call our flying toolbox. The flying toolbox consists of an aerial photography which is in this bucket down here, we have a radar, a snow thickness radar, which is mounted beneath the skids back there. We have a laser scanner and pyrometer on the front over here. And the whole thing will be combined together with an INS and GPS so that we know where we are and how we are orientated in a 3-D space. It is all driven with an electronics control unit which is in the centre here. This time around we also have a microwave radiometer from our Japanese colleagues which is installed in the boot there. So we fly about 60 nautical miles in one direction, then turn 120 degrees, fly 60 nautical miles in the next direction and then fly back to the ship.
What I like most about working in Antarctica is that so many people from so many different skills come together, work seamlessly, know what they are doing and we are all working towards one goal of gathering as much data as possible on sea ice environment down here.