| Summary: | Emitted by fires, black carbon aerosols (rBC) perturb the atmosphere's physical and chemical properties and areclimatically active. Sedimentary charcoal and other paleo-fire records suggest that rBC emissions have variedsignificantly in the past due to human activity and climate variability. However, few paleo rBC records exist toconstrain reconstructions of the past rBC atmospheric distribution and its climate interaction. As part of the internationalRoosevelt Island Climate Evolution (RICE) project, we have developed an Antarctic rBC ice core recordspanning the past ~65 Kyr. The RICE deep ice core was drilled from the Roosevelt Island ice dome in WestAntarctica from 2011 to 2013. The high depth resolution (~1 cm) record was developed using a single particleintracavity laser-induced incandescence soot photometer (SP2) coupled to an ice core melter system. The rBCrecord displays sub-annual variability consistent with both austral dry-season and summer biomass burning. Therecord exhibits significant decadal to millennial-scale variability consistent with known changes in climate. GlacialrBC concentrations were much lower than Holocene concentrations with the exception of several periods of abruptincreases in rBC. The transition from glacial to interglacial rBC concentrations occurred over a much longer timerelative to other ice core climate proxies such as water isotopes and suggests . The protracted increase in rBC duringthe transition may reflected Southern hemisphere ecosystem / fire regime changes in response to hydroclimateand human activity.
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