USAP-DC

Understanding climate change on Earth requires significant insight on geochemical and geobiological cycles in both polar regions and many environments in between. Methane is a major focus because of its substantial sediment loading and its high atmospheric heat absorption as a greenhouse gas. While the Arctic has been the primary climate change focus for studies on methane, the Antarctic’s Ross Sea, embedded with a vast ephemeral reservoir of carbon, has been recognized to have an extensive bottom ocean layer – sediment interface that is one of the most rapidly warming regions on Earth. New studies are needed to test the significance of potentially vast transitory gas hydrate carbon reservoirs present in the Ross Sea and provide a thorough assessment of methane reservoirs in the Southern Ocean. The focus on the Ross Sea is justified by recent drilling expeditions, which suggest a susceptibility of the Ross Sea to climatic fluctuations. This large carbon reserve appears to be sealed in the form of gas hydrate as evidenced by wide-spread seismic evidence. Intriguingly, recent recognition of similar seismic data indicates that this carbon reservoir has been underestimated due to carbon storage in deep sediment hydrates. The proposed project will serve as a foundation for improving both future simulations of oceanic carbon and the interpretation of past paleo-oceanographic cycles. In this project, plans are presented to explore a possible extensive gas hydrate reservoir in Ross Sea sediment and determine whether climate change could be influencing this region. This large carbon reserve appears to be held in the form of gas hydrate as evidenced by key seismic data. This indication of warming and ice melting coupled with high thermogenic gas hydrate loadings suggest the Ross Sea is an essential environment to determine contributions of current day and potential future methane, petroleum, and glacial carbon to shallow sediment and water column carbon cycles. The project will compare carbon source(s) and cycling within phytoplankton, glacier ice, shallow sediment carbon, oil sourced from deep sediment, and methane trapped in gas hydrates. Data collection will include seismic profiling, geochemistry, and geo-microbiology parameters conducted via two field campaigns in the Ross Sea, tentatively planned for December/January 2022/2023 and February/April 2024. The diverse team includes experts in geophysics, geochemistry, ocean chemistry, geo-microbiology and isotope geochemistry. Ultimately, the project aims to create baseline data of present-day conditions in the Ross Sea to provide capability for assessing future anthropogenic influence on carbon cycling. In addition to the scientific activities, the project has extensive educational activities, since education related to climate change requires thorough provision of information across all academic levels, government and the public. The project will fund four graduate students and support the training of undergraduate researchers. Results will be disseminated internationally to non-scientific audiences through field blogs, PI Websites, numerous education and outreach activities, as well as being incorporated into graduate and undergraduate courses. Finally, this project will provide training and support for undergraduate, graduate, and early career researchers at a Hispanic Serving Institution. 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.

Person	Role
Bangs, Nathan	Investigator and contact

Antarctic Ocean and Atmospheric Sciences

Award # 2044391

USAP-2044391_1

Deployment	Type
NBP2402	ship expedition

None in the Database