Unraveling the history of the Greenland Ice Sheet from its internal radiostratigraphy
The internal structure of glaciers and ice sheets, revealed by ice-penetrating radars, has transformed our ability to understand ice evolution. Two investigators propose to use a recently developed compilation of available radar data from Greenland, in combination with ice-flow models, to increase understanding of the history of the Greenland Ice Sheet that will provide context for its response to current and future changes. This is the first time such a project is possible across most of the Greenland Ice Sheet to address how the climate and the ice sheet have changed over time. The major objectives of the proposed work include: 1) validating inferences from the recently available ice-sheet-wide dated radiostratigraphy of the Greenland Ice Sheet against those from internal reflections mapped by targeted ground-based and airborne data collected along flowlines; 2) defining and applying strategies to use Greenland Ice Sheet radiostratigraphy; to constrain its history and to evaluate hypotheses regarding its evolution; 3) determining reconstructions of Greenland's past climate and ice flow that match the radiostratigraphy; and 4) providing a foundation for future continental-scale ice-flow modeling that will seek to assimilate an extensive radiostratigraphy. Broader impacts will include support of two early-career investigators, mentoring graduate and undergraduate students, public outreach, and incorporation of the research into formal classes.