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Summary:Maintenance and Update Frequency: asNeeded Statement: Unknown Incorporating the distribution of 'hot rocks' in East Antarctica into ice sheet models, will improve predictions of ice sheet behaviour and potential sea-level change, according to new Australian research. Speaking at the 'Strategic Science in Antarctica' conference in June, Dr Chris Carson from Geoscience Australia, said naturally occurring 'heat-producing elements' - mainly uranium, thorium and potassium - present in certain rock types found in Antarctica, contribute to local and regional-scale variation in heat flow underneath the ice sheet. They do this by generating tiny amounts of heat by radioactive decay. 'These regions of elevated heat flow potentially can contribute to ice surging and ice stream flow,' Dr Carson said. Sub-glacial heat flow under the West Antarctic ice sheet has been measured at a number of sites and found to be elevated due to active rifting and volcanism. However, crustal heat flow beneath the East Antarctic ice sheet is poorly understood, and instead, a broadly uniform heat flow across much of the region is often assumed in ice sheet models. Such assumptions ignore the natural variability of heat flow due to variations in the sub-glacial geology. To illustrate the scale and importance of this variability, Dr Carson and colleagues from the Australian Antarctic Division, Antarctic Climate and Ecosystems Cooperative Research Centre, University of Melbourne and the University of Texas, recently published a paper in the Journal of the Geological Society, London, describing the distribution of hot rocks, and their impact on regional heat flow, in different parts of the Australian Antarctic Territory. In a 275 km transect along the Prydz Bay coastline - running from the Vestfold Hills to the Amery Ice Shelf - heat production values for individual rock types (derived from geochemical analysis of the rocks) ranged from 0.02 µW per cubic metre to almost 66 µW per cubic metre (1 µW [micro Watt] is 0.000001 Watts). 'There is ...