DOMINOS (Disintegration of Marine Ice Sheets: Novel Optimized Simulations)

There is growing consensus that Thwaites Glacier, West Antarctica, is unstable and vulnerable to collapse. However, there is significant disagreement in projections of rates of mass loss, with some studies suggesting century to millennial scale retreat and others forecasting more catastrophic disintegration. These disagreements are significant because rapid disintegration of Thwaites and adjacent glaciers could potentially trigger or accelerate collapse of significant portions of the West Antarctic Ice Sheet with implications for global mean sea level rise (SLR) in the coming decades. Predicting rates of ice loss from Thwaites Glacier is currently hampered by a lack of reliable models of ice fracture and breakaway (iceberg calving) and the interactions between calving and climate change. Our study addresses this major knowledge gap, and is motivated by the need to improve sea level projections critical for policy and planning.

Projected rates of sea level rise from the West Antarctic Ice Sheet (and Thwaites Glacier in particular) have large uncertainties due to difficulties in understanding and projecting the calving and dynamic processes that control the ice sheet stability. This uncertainty is magnified by the poorly understood connection between calving processes, ice sheet stability and climate. To address these uncertainties, our proposal seeks to explicitly resolve the processes that could cause retreat and collapse of Thwaites Glacier using a novel ice-dynamics model suite. This model suite includes a discrete element model capable of simulating coupled fracture and ice-flow processes, a 3D full Stokes continuum model, and the continental scale ice-dynamics model BISICLES. Ice dynamics models will be coupled to an ocean forcing model suite including simple plume models, intermediate complexity 2-layer ocean models and fully 3D regional ocean models. This hierarchical approach will use high-fidelity process models to inform and constrain the sequence of lower-order models needed to extrapolate improved understanding to larger scales and has the potential to radically reduce uncertainty of rates of marine ice sheet collapse and associated sea level rise. The large-scale modeling approach will be tested and implemented within the open source BISICLES ice dynamics model.

Our education and outreach strategy has several overlapping strands.

Engagement with under-represented students: The first strand, led by UM, involves proactive outreach to populations that are under-presented within STEM fields. We will recruit undergraduate students from nearby community colleges to participate in summer research programs at the University of Michigan. These community colleges serve an economically diverse set of students and our goal is to recruit students from under-represented backgrounds that have had fewer opportunities to experience research. PI Bassis will serve as the primary mentor for the students, and graduate students or PDRAs will act as secondary mentors. We will also proactively provide each student with career planning, advice about graduate school, and general mentoring tailored to his or her needs. We will monitor this population of students to determine if a research experience played any role in their academic trajectory.

Outreach Ypsilanti Schools: The Ypsilanti school district, although in close geographic proximity to the University of Michigan, has markedly different demographics. Ypsilanti Public Schools have about 4,000 students: 64 percent are African-American, 5 percent are Hispanic. Our goal is to interact with these students as possible by attending local science fairs and career days, to make them aware of career opportunities in STEM and Earth Science.

Schools in UK: Outreach activities from St Andrews will capitalize on the existing impact activities for CALISMO, through the highly successful GeoBus project. FGeoBus delivers NERC science to schools by developing workshops based on research outcomes, but fit to the science curriculum (National 4, 5 and Higher in Curriculum for Excellence, Scotland; key stages 3-5 for the National Curriculum in England, Wales and Northern Ireland). PI Benn and undergraduate interns will develop teaching materials and activities to help pupils understand the impact of greenhouse warming on glaciers, ice sheets and sea levels, and engage them in discussion about the importance of these topics to their lives.

Outreach to stakeholders - increasing community participation: Glaciological and climate research is often motivated by the need for accurate sea level projections to inform policy and planning. However, what scientists assert about the usefulness of their work does not necessarily reflect stakeholder's perceptions of the usability of that work: climate research done with some social end goal in mind often fails to be taken up by the relevant practitioners. Graduate student Elizabeth Ultee is currently examining statements of usefulness made by glaciology/sea-level researchers alongside statements of usability made by practitioners including urban planners, the US National Parks Service and insurance risk analysts to identify gaps and recommend action to make available the information planners need. This will inform best practice to maximize the usefulness of sea level projections in local planning and adaptation plans.