This presentation is a follow-up to the work Kristin Poinar presented in Nov 2018.
ABSTRACT: Each summer, a volume of the Greenland Ice Sheet equivalent to 1-2 Lake Erie's melts. Much of the meltwater reaches the ocean, but its path is neither direct nor simple: on its way, the meltwater interacts with the ice sheet itself in ways that can affect ice flow and further sea-level rise. A number of hypotheses about the effect of these water-ice interactions on the long-term behavior of the ice sheet have recently emerged. I use a suite of remote sensing observations and numerical models to test the limits of what is possible and physically realistic within these ideas. My results provide new constraints on the likely future dynamic behavior of the Greenland Ice Sheet and its contribution to global sea level. I will present data on large meltwater lakes and rivers that form on top of the ice sheet, aquifers within the ice sheet, and deep crevasses that move water from these systems to the base of the ice sheet, where it can change the flow speed and flow patterns of the ice sheet above.
BIO: Kristin Poinar is an Assistant Professor at the University at Buffalo Department of Geology. She has worked on ice in Greenland, Antarctica, Alaska, and Washington State. She uses remote-sensing observations and physically based models to constrain the bounds of what is likely to happen in the future of earth’s cryosphere.