EDGE
Exploring Dynamic Greenhouse-gas Emissions at the Margins of the Antarctic Ice Sheet
PI: E. Attias (UTIG)
Collaborators: M. D. L. F. Ruiz (Université Libre de Bruxelles), H. M. Moreno (Univ. of Southampton)
West Antarctica experienced a significant ice-sheet retreat during LGM, manifested by isostatic rebound, continental uplift, and, potentially, the accumulation of freshwater masses in the subsurface. To reconcile the conflict bottom-up estimates of the global carbon budget, the EDGE project will (1) Asses the potential of large-scale methane release from Antarctic groundwater discharges and (2) explore the possible periodic states of hydrates in Antarctica. These processes lead to self-sustained hydrate layers' cyclic formation and dissolution, independent of external triggers such as anthropogenic warming, sea-level fluctuations, or large-scale planetary cycles.
Methane-to-carbon (M2C) biotransformation may significantly increase the risks of spontaneous gas migration, geomechanical failures, and gas influx into the ocean from supposedly stable systems. The intrinsic processes that couple groundwater discharge from springs formed during glacial retreat, methane dissociation, and biotransformation of CO2 and subsequently to carbon are poorly understood. EDGE aims to gain new insights into these processes that may have a significant role in the global carbon budget.
To study the complex processes in West Antarctica, an international team of scientists will combine marine EM, multichannel seismic, core, and water sampling datasets for geochemical and biological analysis. This will support effective medium modeling and new geotechnical and numerical modeling to estimate the volumes of methane biotransformation to carbon influx to the Southern Ocean and subsequently added to the global carbon cycle.
Survey Plan: A map illustrating the proposed CSEM and multichannel seismic (MCS) experiment at the Antarctic Peninsula. OBEMs will be strategically placed to record continuous long-period MT data throughout the survey. This effort will be complemented by integrating legacy core data accessible through OSU's NSF-supported Marine Geology Repository. The distribution of bottom heat flow measurements adapted from Fuchs et al., (2023). Numerous anomalies in sea surface salinity (SSS) and temperature (SST) have been identified within the area targeted for our proposed survey Boyer et al., (2018).
