Summary
Black carbon (BC), the primary light-absorbing aerosol in the atmosphere, is emitted by the incomplete combustion of biomass and fossil fuels affecting the radiative balance of the atmosphere. As a contributor to climate change, BC may rival greenhouse gases such as methane. Emission estimates of BC suggest increasing levels of BC over the 20th century as a result of fossil fuel combustion and changes to land use. However, large uncertainties exist in historical emission estimates, the spatial distribution of BC in the atmosphere and its deposition rate. Using ice cores from WAIS (WDC06A), the South Pole, the Norwegian-U.S. Scientific Traverse of East Antarctica (NORUS) and Law dome, we have investigated the spatial and temporal variability of BC deposition to Antarctica over the 20th Century. The records reveal similar BC depositions rates to WAIS and Law Dome, which were generally double the flux of BC to South Pole and sites along the NORUS traverse. No significant increase in the BC flux was observed during the 20th century suggesting changes in Southern Hemisphere human activity had little impact on BC deposition to the sites. Instead changes in BC appear to be associated with Southern Hemisphere climate change.