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Ice sheet stability
ICECAP’s aerial surveys and instrument deployments purpose to assemble data to enhance modelling of ice sheet dynamics, and our understanding of the position of the Antarctic ice sheet in international local weather and sea degree rise.
About 2200 billion tonnes of snow accumulates on the Antarctic continent every year, which is equal to about six millimetres of world sea degree. This ice acquire is offset by ice loss, because it flows from the inside to the coast, the place it melts and calves off as icebergs.
“The construction and composition of the bedrock beneath the ice impacts the trail and pace of ice move,” Dr Roberts mentioned.
“So we wish to know the place there are mountain ranges, basins or flat plains beneath the ice and what kind of rocks are beneath there. For instance, are they ‘sizzling’, naturally radioactive rocks that may lubricate the motion of the ice sheet by contributing to the formation of liquid water at its base?”
To search out out, the workforce conducts geophysical surveys in a venerable Basler BT-67 (a modernised DC3), bristling with devices and sensors, together with an ice-penetrating radar, laser altimeter, digital camera, gravimeter and magnetometer.
These devices measure the thickness, inner construction and floor elevation of the ice, the presence of liquid water, and bedrock depth, construction and composition.
Thus far the worldwide effort has mapped greater than 700,000 kilometres of survey traces, and contributed to greater than 3500 publications, together with greater than 100 that knowledgeable the Intergovernmental Panel on Local weather Change experiences.
ICECAP has additionally helped establish the situation of ice a couple of million years outdated (Australia’s Million Yr Ice Core Mission drilling website) at Little Dome C, about 1200 km from Casey (see radargram picture).
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