03 August, 2016 by Staff Reporter
A team of researchers with ICECAP (the International Collaboration for Exploration of the Cryosphere through Aerogeophysical Profiling) has been using long-range drones to monitor more efficiently changes to the East Antarctic Ice Sheet.
Between February and March 2016, the team tested 'Tiburon Junior', a long-range drone developed by US engineering company Intuitive Machines. The flights represented the next phase of the ICECAP project which, over the past seven years, has been monitoring changes in the East Antarctic Ice Sheet, as well as surveying the ice sheet's structure and underlying bedrock topography and geology.
The drones are carrying similar scientific equipment normally installed in a seven tonne Basler BT-67, the aircraft the project has been traditionally using for aerial surveying. Australian Antarctic Division glaciologist Dr Jason Roberts, part of the ICECAP research team, says the Tiburon Junior drones have a much greater range and the ability to fly more slowly, improving the resolution of the data. He believes the drones will allow the project team to more efficiently monitor ice sheet change, as well as to explore new and difficult to access areas in the continental interior and offshore.
"While the Basler remains our primary workhorse, the drones give us more flexibility to operate over the continental shelf, because they don’t need safety equipment to fly over water. So they can fly further and they can fly over sea-ice covered areas that would be difficult to get to by ship," says Dr Roberts.
Dr Jamin Greenbaum, a geophysicist from the University of Texas Institute for Geophysics, is also a member of the ICECAP research team. He believes that the use of the new long-range drones will be hugely beneficial in strengthening the data they collect.
"Monitoring the ice sheet – observing whether the ice surface is rising or falling over time – with Junior, will allow the Basler to focus on areas requiring the combined set of heavier instruments. Junior also burns far less fuel than any piloted aircraft, so it is a more appropriate platform for flying where larger aircraft have already surveyed," says Greenbaum.
The ICECAP research project is a collaboration between the Australian Antarctic Division, Antarctic Climate and Ecosystems Cooperative Research Centre, Australian Research Council Special Research Initiative, the University of Texas at Austin Institute for Geophysics, the US National Science Foundation, the UK’s Natural Environment Research Council, and the G. Unger Vetlesen Foundation.
At close to five kilometres thick in some places, the East Antarctic Ice Sheet it is the largest ice sheet on the planet. If it were to melt, global sea levels would rise by over 50 metres.
The ICECAP project aims to uncover information that will improve modelling of ice sheet dynamics and the understanding of the role of the East Antarctic Ice Sheet in global climate and sea level rise.
Antarctica accumulates about 2,200 billion tonnes of snow a year, the equivalent to approximately a six millimetre increase in global sea levels. The accumulation is offset by the loss of ice as it flows from the interior to the coast, where it calves off as icebergs, or melts into the ocean. The balance of these losses and gains determines whether Antarctica causes overall rises or falls in sea level. Understanding the flow path of this ice, and how it might be changing, is a critical to predicting future fluctuations in global sea levels.
"Bedrock topology and composition affect the path and speed of ice flow," says Dr Roberts.
"So we want to know where there are mountain ranges, basins or flat plains under the ice and what type of rocks are under there. For example, are they 'hot', naturally radioactive rocks that can lubricate the movement of the ice sheet by contributing to the formation of liquid water at its base?"
To find out, the airborne ICECAP toolkit includes ice-penetrating radar, laser altimetry, a camera, gravity meter, and geomagnetic equipment, to measure ice thickness and structure, ice surface elevation, the presence of liquid water, and bedrock depth, structure and composition.
