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Abstract

Black carbon (BC) is one of the predominating drivers concerning radiation budget modifications of snow surfaces as it can cause albedo decrease. Therefore, this leads to accelerated snow melting and thus to modifications of feedback mechanisms between components of the cryosphere and atmosphere. To investigate and quantify the detailed BC-induced processes in polar regions, snow samples collected during different campaigns in the Antarctic and the Arctic, especially during the MOSAiC expedition are analyzed in the chemical laboratory employing a Single Particle Soot Photometer (SP2) and the nebulizer Marin 5. Doing so, it was found that prevalent saline character of the snow collected on sea ice influences the results of SP2 analysis in a way that BC concentrations become significantly underestimated. We present here a method that was developed for quantification and correction of those effects since a significant number of the MOSAiC samples in particular include such sea salt impurities. Applying the methods to the whole MOSAiC data set will allow for the first time to quantify year-round human-caused pollution in the central Arctic and related changes of the surface energy budget. The samples from Antarctica will allow for a bipolar comparison of physical and chemical snow properties.