RAPID: US-Korean collaboration to build a Ross-Amundsen Ice Core Array (RAICA) along the West Antarctic coastline

The West Antarctic coastline is changing rapidly: it is thinning, losing mass, and buttressing ice shelves that are critical for future stability of the ice sheet are retreating. Despite observed change caused by ice-ocean-atmosphere interactions perturbed by both internal and forced climate processes (e.g., tropical Pacific Ocean variability, ozone depletion, greenhouse gas warming), there are few direct measurements along this coastline. Ice rises, which are regions of grounded ice within ice shelves, are ideal ice-core sites. Ice rises line this region, allowing for reconstruction of coastal climate and environmental parameters dating back decades to millennia at annual resolution. Retrieval of a 150-m-long ice core from an ice rise in this region will expand our understanding of critical processes relevant to observed coastal change over a timespan of several centuries. Shallower cores also collected on the ice rise, flanking the central 150-m core, will validate the amount and spatial variability of surface change across this ice rise, providing constraint for airborne observations, satellite observations, climate models, and reanalysis datasets. The project forms a new collaboration between a U.S. researcher and the South Korean Polar Research Institute (KOPRI), who will provide the bulk of the logistics, including the use of their research vessel, RV ARAON. The project will also train a graduate student. This RAPID proposal relies on KOPRI logistics to accomplish the field aspects of this project. The participants will deploy on the RV ARAON from December 2023 – February 2024. The U.S.-South Korean team will drill one to two 150-m ice core from the center of the peninsula, along the local ice divide. Further, to assess surface-mass-balance (SMB) variability, the team will drill a series of 10- to 15-m ice cores on the flanks of the ice divide. Martin Peninsula, between the Getz Ice Shelf and the Dotson Ice Shelf, has been chosen as the primary site based on existing airborne snow radar data, and the high snow accumulation rate, which preserves high-resolution paleoclimate information. The specific site will be chosen based on both scientific value and logistical constraints associated with the RV ARAON cruise. The ice-core data will be used to characterize climate variability, extremes, and trends along the coastal West Antarctic Ice Sheet — over recent decades and centuries. 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.