Lab-crafted glaciers: exploring ice sheet instabilities using experimental ice analogs

The Marine Ice Sheet Instability (MISI) hypothesis suggests that marine ice sheets grounded on retrograde slopes below sea level are prone to rapid and irreversible retreat, posing a significant threat to global sea-level rise. However, this instability is exceedingly sensitive to the specific rheology of ice. In this study, we aim to experimentally investigate MISI by employing various ice analog materials to simulate the dynamics of ice sheets and ice shelves in a laboratory environment. By using materials such as gelatin, kaolin, and flubber, we aim to find an analog that closely mimics the power-law rheological properties of glacial ice in the tertiary creep regime. During flow, all these materials are non-Newtonian, but their flow behavior stems from different microscopic mechanisms (i.e., polymers, particulate suspensions, structure formation and degradation). Our overarching goals are to observe the recession of the grounding line, increased ice flux, and potential hysteresis effects in the MISI. These observations will provide empirical evidence for the MISI hypothesis and help refine Glen’s flow law to model the faster flowing regimes more accurately in glaciers. The significance of this research lies in its potential to enhance our understanding of ice sheet dynamics under the influence of climate change. As global temperatures rise, the stability of marine ice sheets becomes increasingly uncertain, making it crucial to improve predictive models for future sea-level rise.