USAP-DC

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project's goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth's system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column.

Person	Role
Robinson, Laura	Investigator

Antarctic Earth Sciences

Award # 0902957

NSF-ANT09-02957_1

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals	None	exist

1. Guillermic, M., Lalonde, S. V., Hendry, K. R., & Rouxel, O. J. (2017). The isotope composition of inorganic germanium in seawater and deep sea sponges. Geochimica et Cosmochimica Acta, 212, 99–118. (doi:10.1016/j.gca.2017.06.011)
2. Margolin, A. R., Robinson, L. F., Burke, A., Waller, R. G., Scanlon, K. M., Roberts, M. L., … van de Flierdt, T. (2014). Temporal and spatial distributions of cold-water corals in the Drake Passage: Insights from the last 35,000 years. Deep Sea Research Part II: Topical Studies in Oceanography, 99, 237–248. (doi:10.1016/j.dsr2.2013.06.008)
3. Samperiz, A., Robinson, L. F., Stewart, J. A., Strawson, I., Leng, M. J., Rosenheim, B. E., … Santodomingo, N. (2020). Stylasterid corals: A new paleotemperature archive. Earth and Planetary Science Letters, 545, 116407. (doi:10.1016/j.epsl.2020.116407)