Title: Modeling microphysical processes in large-scale ice sheet models
Abstract: Mass loss from the Antarctic Ice Sheet occurs due to the viscous ice flow of glaciers from the interior of ice sheets towards the ocean, along with brittle fracture of ice into icebergs. Viscous flow and brittle fracture of ice are governed by microphysical processes that occur on scales of ice crystals or smaller. However, incorporating physics on these small spatial and temporal scales into ice sheet models is made difficult by gaps in our physical understanding of these microphysical processes and by the computational cost of models that resolve them. Therefore, many of these explicit processes of ice deformation and ice fracture are neglected in current ice sheet models. In this talk, we examine the implications of neglecting the small-scale processes governing both ice deformation and ice fracture. Further, we present a bulk parameterization method for incorporating ice crystal-scale processes into models of viscous ice flow, and we show that this parameterization could explain the variation in ice flow regimes inferred by a range of laboratory and field studies and provides a way of parameterizing the effect of varying flow conditions on future ice sheet behavior. We further discuss paths forward for incorporating ice fracture behavior into these models as well.
Zoom Link: https://gatech.zoom.us/j/95963290955
Recording: Zoom Recording