Subglacial Access Working Group: Access Drilling Priorities in the Ross Ice Shelf Region

Summary: The Ross Ice Shelf (RIS) Region, including the ice shelf, associated ocean cavity, and coastal and upstream environments, is a dynamic system resulting from the interactions between ice, ocean, freshwater, and geology. Beneath the ice streams and outlet glaciers that feed the RIS, subglacial hydrological systems redistribute water and nutrients, yet the ultimate impacts of these systems on both ice flux into Ross Ice Shelf and freshwater and nutrient flux into the sub-ice-shelf ocean cavity are poorly understood. Aqueous and sedimentary subglacial environments are inhabited by microorganisms and represent a potentially large planetary reservoir of microbes and (microbially derived) organic carbon transported through the subglacial system and into the sub-ice-shelf cavity, perhaps of the same magnitude as that in the surface oceans.

Glaciological, oceanographic, geological, and biological research in this region benefits from a decades-long history of diverse scientific observations, which provides foundation for the development of focused hypotheses and enables interpretations of new findings in the context of decadal scale ice sheet and ocean evolution, which is difficult to replicate in many other parts of Antarctica. Materials collected from subglacial environments in the region are still rare; to date, only two subglacial lakes (Whillans and Mercer; SLW and SLM) and one grounding zone (Whillans Ice Stream; WGZ) have been cleanly drilled and accessed for sample collection. Current data from these studies indicate widespread microbial activity and potentially novel phylogenetic diversity and evidence for changing environmental conditions on surprisingly rapid timescales. Understanding the scope and pace of change and quantifying the importance of water and nutrient movement require scientific drilling in this region. Such campaigns will address questions related to the National Academies of Sciences’ 2015 report Strategic Priority I (How Fast and by How Much Will Sea Level Rise? The Changing Antarctic Ice Sheets Initiative) component i: A multidisciplinary initiative to understand why the Antarctic ice sheets are changing now and how they will change in the future, component ii: Using multiple records of past ice sheet change to understand rates and processes, and Strategic Priority II: How do Antarctic biota evolve and adapt to the changing environment? Decoding the genomic and transcriptomic base of biological adaptation and response across Antarctic organisms and ecosystems.