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  • This proposal addresses the geometry and flow dynamics of three large ice caps in the Canadian arctic islands, with implications for glacier mass balance and the rate of sea-level change in a warming world. The work involves a combination of airborne 60 MHz radar to measure ice thickness, which is at present poorly known for these ice caps, and satellite remote sensing of ice velocities. Thickness and velocity data allow calculation of mass loss by iceberg production from the major outlet glaciers of these ice caps. Iceberg production is widely acknowledged as the least well known element in the mass balance of arctic glaciers, and indeed, ice masses worldwide. Internal radar-reflecting horizons and bed power-reflection coefficients also indicate glacier thermal structure. The data will be used as boundary conditions in three-dimensional numerical modelling studies of the response of these ice masses to climate change through time

  • The research will experimentally test the ice-segregation model of rock fracture in the context of near-surface bedrock. Experiments at the Caen Cold Laboratories will monitor the effects of different thermal regimes, moisture conditions and material properties on rock fracture, ice segregation and frost heave in large blocks of limestone and sandstone. Experimentally-formed fractures and segregated ice will be compared with predictions from two theoretical models of rock fracture and frost heave, and the observed rock fractures compared with contemporary and relict weathering profiles. By integrating curiosity-driven research on important Earth-surface processes (rock fracture, ice segregation) with their practical consequences (rock heave/settlement), the study will have international significance to cold-regions Earth science and engineering.

  • The processes by which frost shatters rock are subject to controversy. The main objective of the proposed research is to develop a new methodology for experimentally testing a model of ice segregation in permafrost. Using specialist cold-room facilities in the CRNS Centre de Geomorphologie, Caen (France), the methodology will simulate the bedrock thermal and hydrological regime at the top of cold permafrost in order to determine whether growth of segregated ice within the simulated permafrost shatters a large block of frost susceptible rock (chalk). Verification of the ice-segregation hypothesis by the proposed experiment would have international significance to the fields of permafrost science, engineering and rock weathering because it would emphasise the unified nature and consequences of ground-ice development in fine-grained soils and rocks.

  • The nature of ice-sheet flow between Ridge B and the Vostok sub-ice lake will be determined from a series of measurements and numerical models. Datasets available foe measurements include airborne radar(for ice thickness, internal ice layering, crystal orientation fabric development, and sub-ice conditions), ERS-1 altimetry (for the ice-surface elevation) and interferometric SAR (for the ice-surface velocity). The measurements will form boundary conditions for state-of-the-art models of ice flow. Model results will establish the true nature of ice flow in this region of Antartica. Results will be fundamental to (1) the depth-chronology of the Vostok ice core (2) the examination of the ice-water interaction above the large Vostok subglacial lake and (3) developing traditional models of ice flow in central regions of ice sheets that currently do not replicate the true glaciology.