Antarctic Ice Front, Shelf and Grounding Line Dynamics from High-resolution, Commercial Satellite Imagery and Elevation Data

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Predictions of sea-level rise depend on the response of Antarctica’s ice shelves to changes in the ocean and atmosphere. Thinning and collapse of these ice shelves may lead to rapid, runaway retreat of the ice sheet. It is therefore critical to understand the processes controlling ice-shelf stability. Many of these processes, such as ice rifting and crevassing, occur too quickly or are too small to be seen in most satellite images, but are also too large and remote to measure in the field. The NSF-supported Polar Geospatial Center (PGC) has compiled a massive archive of high-resolution satellite imagery and surface-elevation data collected from commercial satellites, spanning over a decade, that can fill this observational gap and improve our understanding of ice-shelf change. This project will provide a first, comprehensive application of commercial satellite imagery, in combination with other datasets, to measure changes in Antarctic ice shelves and potential impacts to ice-sheet stability. This project will also include undergraduate and graduate students and leverage existing resources at the Byrd Polar and Climate Research Center for education and outreach programs.The project will use the PGC archive of commercial satellite imagery (CSI) and high-resolution digital elevation models to measure surface features, flow and strain rates, and surface elevation change, with high spatial and temporal resolution, at a set of critical Antarctic ice shelves. A set of measurement objectives will be used to assess the capabilities of CSI for resolving significant changes in grounding lines, ice shelves, and ice mélange. The team will use these measurements to address outstanding science questions regarding the interaction between the ice shelf and grounding line, the structural and dynamic evolution of ice shelves and mélange, and ice-front stability. We will combine our measurements with complementary datasets, such as ICESat-2 altimetry and ice velocity from Landsat and Sentinel satellite constellations, as well as airborne measurements from NASA’s Operation IceBridge, to provide a more comprehensive record of change. This project will produce visuals, including three-dimensional fly-throughs, that will be used in outreach activities to spark interest in Antarctic science among diverse populations. This project will support the training of a graduate student and will develop methods for utilizing CSI in glaciology and related applications. Finally, the results will help guide the PGC’s future CSI tasking and data production strategies to best serve science community objectives.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.