video transcript

Aboard the research vessel, Aurora Australis,. scientists from eight countries are on a mission to map the sea ice of Antarctica. But their not doing it from the air. They need to know the impact of global warming on its thickness and, for that says Dr Guy Williiams, they need to measure the ice from below. (SOUNDBITE) (English) DR GUY WILLIAMS, AUV SPECIALIST, ANTARCTIC CLIMATE AND ECOSYSTEMS COOPERATIVE RESEARCH CENTRE SAYING: "So the 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 the thickness and without the thickness we won't know the total volume or the actual amount of sea ice." The team is using an autonomous underwater vehicle - a submarine - to provide the information they need. It's programmed to travel in a grid pattern, about 20 metres below the ice, using multi-beam sonar to measure its topography. SOUNDBITE) (English) DR GUY WILLIAMS, AUV SPECIALIST, ANTARCTIC CLIMATE AND ECOSYSTEMS COOPERATIVE RESEARCH CENTRE SAYING: "The multibeam sonar that we have on this AUV will provide us with a three dimensional view of the underside of the sea ice and that will together with the surface measurements that we are going to get from the other platforms like the helicopter or the terrestrial LIDAR, we'll have a full 3-D map if you like of the entire sea ice floe." And the results so far are exactly what the scientists had hoped for. In conjunction with data provided by satellite and helicopter surveys, marine glaciologist Jan Lieser says scientists will be able to answer one of the most important questions about climate change and it's impact. (SOUNDBITE) (English) DR JAN LIESER, MARINE GLACIOLOGIST, ANTARCTIC CLIMATE AND ECOSYSTEMS COOPERATIVE RESEARCH CENTRE SAYING: "When we know that, 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 but also the biosphere." It's a long term mission but one the scienists say is crucial to assessing the overall health of the planet.