biir cost preview preparatory materials. biir can help answer these science questions refined...
Post on 19-Dec-2015
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BIIR Can Help Answer These Science QuestionsRefined science questions derived in part from the St. Petersburg ISMASS Meeting (July 2008)
(in response to downselect review board)
• How can IPCC error bounds on the present mass balance of the polar ice sheet and their contribution to global sea level rise be reduced? – Ice thickness used to compute flux has not been systematically measured around the perimeter of the
ice sheets. BIIR will conduct a circum-ice-sheet campaign to accurately measure ice thickness and refine flux estimates through combination with DESDYNI measurements of surface velocity.
• What causes observed, abrupt changes in ice sheet motion? Does a rapid change in a glacier always lead to a large change in the ice sheet volume?– Restraining forces limit the outward flow of ice. Changes in the longtitudinal, basal or lateral boundary
conditions leads to a commensurate response in flow. BIIR will measure for the first time the 3-d dimensional physical properties of the surface and base of select glacier basins Information on 3-d basal topography and the distribution of basal water will be provided to modelers for estimating the present stress regime of the ice sheet and determining whether basal geometries support quasi-equilibrium configurations.
• How will the mass balance and dynamics of the ice sheets change in the future?– BIIR will produce 3-d maps of basal topography, and surface and basal reflectivity. BIIR will
supplement ICEsat measurements of surface topography by providing information for interpolating between ICEsat ground tracks. The maps will be a primary input for predictive ice sheet dynamics models.
GISMO Lakes Result
Upper Left: Radarsat winter scene.
Upper Right: 150 MHz GISMO surface image
Lower left: Radarsat summer scene
Lower Right: GISMO image on top of Gismo topography (preliminary result in need of a tilt correction)