The occurrence, trends and sources of soot black carbon (BC) in coastal sediments are poorly understood, particularly during the Anthropocene. Two sediment cores, covering the last ~100 years from the US East Coast, off North Carolina and in the Florida Straits, were analyzed for organic carbon (OC), BC fluxes and BC sources. BC fluxes were 0.1 g cm⁻² year⁻¹ at both sites and accounted for 8-22% of total OC. Carbon stable isotope values indicated OC to be of marine origin, while the BC was mostly terrestrially derived, C3-plant material. Radiocarbon values revealed BC originating mostly from fossil fuels or pre-aged carbon (fraction modern of 14−31%) at North Carolina, while in the Florida Strait the BC was mostly derived from biomass burning (fraction modern of 70−74%), in-line with continental (NC) or marine (FS) air mass origins. Ratios of polycyclic aromatic hydrocarbons broadly supported different BC sources at the two sites.

Primary Presenter: Ita Wulandari, National Research and Innovation Agency - BRIN (itaw001@brin.go.id)

Authors:

Ita Wulandari, Research Center for Oceanography - National Research and Innovation Agency, Jakarta, Indonesia.  (itaw001@brin.go.id)

Rainer Lohmann, The University of Rhode Island  (rlohmann@uri.edu)

Samuel Katz, University of Rhode Island  (sdkatz@uri.edu)

Roger Kelly, University of Rhode Island  (rokelly@uri.edu)

Rebecca Robinson, University of Rhode Island  (rebecca_r@uri.edu)